May 2002 Gasification Archive

For more information to help people develop better stoves for cooking with biomass fuels in developing regions, please see our web site: http://www.bioenergylists.org

From hseaver at cybershamanix.com Wed May 1 04:42:56 2002
From: hseaver at cybershamanix.com (Harmon Seaver)
Date: Tue Aug 31 21:37:48 2004
Subject: Info on the Klez.H worm that Eld did _not_ send out
In-Reply-To: <001b01c1f0df$cc4f3200$2a47fea9@md>
Message-ID: <20020501134140.GA32017@cybershamanix.com>

On Wed, May 01, 2002 at 09:11:57AM +0200, Crispin wrote:
>
> Here in the 'bush' people are struggling to get their systems back up and
> running. This is due to the expense (in our currencies) of antivirus
> programs and professional help and the inconvenience and cost of getting
> regularly downoaded updates.
>
> Regards
> Crispin

The biggest and best (and by far the cheapest) step you all could take to
stop email viruses is to quit using Outlook. Download netscape, or pegasus, or
eudora and use them instead.

--
Harmon Seaver
CyberShamanix
http://www.cybershamanix.com

From psanders at ilstu.edu Wed May 1 06:44:41 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:48 2004
Subject: Stove efficiency
Message-ID: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>

Stovers,

First an observation: MUCH less Stoves message traffic in this period of
application for the Shell Foundation funding. Why: 1) People busy on
their own applications, and 2) people NOT wanting to share quite so much
info when the "funding chips" are being discussed, and
3) people are discussing with smaller groups of closer friends.

Whatever the case, let's keep key issues on the Stoves list.

Here is one: Stove efficiency

Someone on the Stoves list previously stated that the energy output from a
unit of fuel is always the same if it is completely consumed, and therefore
the efficiency of the combustion is equal for all stoves that burn
fully. I believe that is a correct statement.

Therefore, the issues of efficiency are in 3 categories:

A). Issues about getting the combustion to be complete. That is, stoves
that smoke certainly must be less efficient than those that do not smoke
(assuming the same fuel).

and

B). Issues of getting the heat into something USEFUL (and that can be
measured??). I keep remembering the "hay box" that continues to cook with
the heat that is already present in the hot pot of ingredients, even when
the stove is off. If we assume that some people would do that, how can
that be measured as efficiency? Part of this is the question of TIME and
the control-ability of the amount of combustion at the desired rates when
needed.

and

C). Cultural (not physical) issues of SOCIAL behavior (cooking practices)
and ECONOMIC realities (cost of the fuels) that may make the above two (A
and B) of less consequence. Examples:
1. Rural primitive cooker (on 3 stones) in a forest with few other people
and such an abundance of wood available that the thought of saving wood
would be beyond imagination.
2. Oven cooking vs "burner-top" cooking in pots vs "food-over-flame"
cooking (as in meat over an open flame).

Stated another way, do we or anybody have functional measurements of
efficiency (other than how much water is boiled in X time by Y amount of
fuel Z)?? And is that even important? I believe that it is important,
but how much effort should we expend on defining and operationalizing some
measures of efficiency?

Happy 1st of May (a holiday for many of you!!)

Paul
Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
Dept of Geography - Geology (Box 4400), Illinois State University
Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders

From crispin at newdawn.sz Wed May 1 08:16:16 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:48 2004
Subject: Netscape etc
Message-ID: <005701c1f134$b0df4460$2a47fea9@md>

Dear Harmon

>The biggest and best (and by far the cheapest) step you all
>could take to stop email viruses is to quit using Outlook.
>Download netscape, or pegasus, or eudora and use them instead.

Agreed. But how would I be able to help my friends? Unless I was able to
convince them to do the same thing I would look like a bump on a log.

It is tough here out on the edge.

Sincerely,
Crispin

From hseaver at cybershamanix.com Wed May 1 08:25:57 2002
From: hseaver at cybershamanix.com (Harmon Seaver)
Date: Tue Aug 31 21:37:48 2004
Subject: Netscape etc
In-Reply-To: <005701c1f134$b0df4460$2a47fea9@md>
Message-ID: <20020501172441.GB32756@cybershamanix.com>

On Wed, May 01, 2002 at 07:10:53PM +0200, Crispin wrote:
> Dear Harmon
>
> >The biggest and best (and by far the cheapest) step you all
> >could take to stop email viruses is to quit using Outlook.
> >Download netscape, or pegasus, or eudora and use them instead.
>
> Agreed. But how would I be able to help my friends? Unless I was able to
> convince them to do the same thing I would look like a bump on a log.

It would help your friends (and everyone else) because then you wouldn't be
part of the problem, spreading viruses. How do you help them by running outlook
yourself? And, of course, you should convince them to do likewise - outlook is a
menance to the internet, a pure virus magnet and propagator. Most other mail
readers work just fine.
I guess I don't understand your statement "I would look like a bump on a
log", if you used a differnt mail reader, very few people would even notice,
unless they bothered to read the whole header statement of the email and saw
"netscape" instead of "outlook".
Of course, people might take notice that you were no longer spreading viruses
or sending out messages about what to do to fix the latest one.

--
Harmon Seaver
CyberShamanix
http://www.cybershamanix.com

From stoves at ecoharmony.com Wed May 1 09:50:18 2002
From: stoves at ecoharmony.com (Grant Ballard-Tremeer)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <1127784211.20020501195035@ecoharmony.com>

Hello Stovers,

Wednesday, May 1, 2002, 4:51:57 PM, Paul, when discussing stove
efficiency wrote:
PSA> A). Issues about getting the combustion to be complete. That
PSA> is, stoves that smoke certainly must be less efficient than those
PSA> that do not smoke (assuming the same fuel).

And, I would add, assuming a number of other things too. I have tested
many smokey stoves which have *overall* efficiencies higher than less
smokey stoves - such as those in figure 6 here:
http://ecoharmony.com/thesis/AppdxE.htm.

The one of the easiest way to increase the heat transfer to the pot is
to force the flame against the (cold) bottom of the pot. This quenches
the flame producing smoke and soot, but the loss of efficiency due to
reduced combustion efficiency is far outweighed by the gain in
increased heat transfer efficiency. I'm sure you know this already,
but "stoves that smoke certainly must be less efficient" is not
entirely true.

PSA> B). Issues of getting the heat into something USEFUL (and that
PSA> can be measured??).

That's what the measurement of efficiency is all about - the ratio of
useful work done to energy supplied.

PSA> I keep remembering the "hay box" that continues to cook with the
PSA> heat that is already present in the hot pot of ingredients, even
PSA> when the stove is off.

An 'efficiency' measure for hay boxes is not difficult to define in my
opinion. To compare hay boxes I would use time as an indicator of
efficiency (time temperature maintained inside the pot above 80°C for
example). To compare stove-haybox combination a good indicator could
be energy input per meal prepared (or water brought to the boil and
maintained above a certain temperature for a predetermined time).

PSA> C). Cultural (not physical) issues of SOCIAL behavior (cooking practices)
PSA> and ECONOMIC realities (cost of the fuels) that may make the above two (A
PSA> and B) of less consequence. Examples:
PSA> 1. Rural primitive cooker (on 3 stones) in a forest with few other people
PSA> and such an abundance of wood available that the thought of saving wood
PSA> would be beyond imagination.
PSA> 2. Oven cooking vs "burner-top" cooking in pots vs "food-over-flame"
PSA> cooking (as in meat over an open flame).

I have discussed some of these issues at
http://ecoharmony.com/thesis/AppdxB.htm - I personally do not believe
that a universal measure of efficiency is useful for comparing stoves.
I believe that we need testing guidelines which can relate to specific
socio-cultural practice, and ensure control where it is necessary, but
are flexible for non-critical factors. This of course means that test
results are internally comparable.

Volunteers in Technical Assistance (VITA) produced 'International
Standards' for stove testing in 1985 "Testing the efficiency of
wood-burning cookstoves" based on extensive consultation, and I
believe most of it is still highly relevant.

Regards
Grant

--
Grant Ballard-Tremeer PhD, visit ECO Ltd on the web at http://ecoharmony.com
64C Fairholme Road, W14 9JY, London
Tel +44-(0)20 7386 7930
Fax +44-(0)870 137 2360 and +44-(0)70 9236 7695
email stoves@ecoharmony.com
HEDON Household Energy Network http://ecoharmony.net/hedon
HEDON on Agenda 21 and the World Summit http://ecoharmony.net/agenda21
-------------------

From fred.p at wam.co.za Wed May 1 11:03:35 2002
From: fred.p at wam.co.za (fred)
Date: Tue Aug 31 21:37:49 2004
Subject: test
Message-ID: <005c01c1f14a$fc9b61c0$718eef9b@fpohl>

Please ignore.... Test.

From crispin at newdawn.sz Wed May 1 11:15:48 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:49 2004
Subject: Netscape etc
Message-ID: <001f01c1f14c$8eb1a5a0$53e80fc4@home>

Dear Harmon

> Of course, people might take notice that you were no longer
>spreading viruses or sending out messages about what to do
>to fix the latest one.

Of course that is true, but by a bump on a log means that people turn to me
to solve many problems and keeping computer systems going - back to XT's (no
kidding) is part of living a techie's life in Swaziland.

What you say is true aobut Nestcape, I hear you, but if we all went to
Netscape people would simply move on to writing viruses for Netscape.

When a little more backup for Linux is available around here (about which I
know nothing at all) and probably after my son the Windows product fundi
learns a lot about it, I will jump to Corel Office for Linux in one leap and
dedicate the time necessary to it.

Now that XP is out and they want a bookkeeper's months salary for a copy in
this country, the pressure is on to change operating systems.

Nuff said!

Regards
Crispin

From adkarve at pn2.vsnl.net.in Wed May 1 15:12:28 2002
From: adkarve at pn2.vsnl.net.in (A.D. Karve)
Date: Tue Aug 31 21:37:49 2004
Subject: Nut-hulled pellets for backup heat
Message-ID: <002701c1f171$546e5580$9551c5cb@adkarvepn2.vsnl.net.in>

Nut hulls represent a woody biomass. I think that they can be mixed with
cattle dung and formed into fuel briquettes. Alternatively they can be
pounded into a powder and extruded into pellets after mixing them with a
suitable binder (e.g. starch paste). The third alternative is to char them
and use the char to make your briquettes in the same manner as the second
alternative.
A.D.Karve
-----Original Message-----
From: First Last <dadelcnu@hotmail.com>
To: stoves@crest.org <stoves@crest.org>
Date: Tuesday, April 23, 2002 9:17 AM
Subject: Nut-hulled pellets for backup heat

>I'm off grid with passive solar heat and PV for electricity. I want to
burn
>pellets for backup heat because of the recycled angle, but I live near
>California's nut country and want to use pellets made from recycled nut
>hulls.
>
>Does anybody know of a nut hull pellet?
>
>_________________________________________________________________
>Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.
>
>
>-
>Stoves List Archives and Website:
>http://www.crest.org/discussion/stoves/200204/
>http://crest.org/discussiongroups/resources/stoves/
>>
>Stoves List Moderators:
>Ron Larson, ronallarson@qwest.net
>Elsen L. Karstad, elk@wananchi.com www.chardust.com
>>
>List-Post: <mailto:stoves@crest.org>
>List-Help: <mailto:stoves-help@crest.org>
>List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
>List-Subscribe: <mailto:stoves-subscribe@crest.org>
>>
>Sponsor the Stoves List: http://www.crest.org/discuss3.html
>-
>Other Biomass Stoves Events and Information:
>http://www.bioenergy2002.org
>http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
>http://www.crest.org/articles/static/1/1011975339_7.html Gasification
>http://www.crest.org/articles/static/1/1011975672_7.html Carbon
>>
>For information about CHAMBERS STOVES
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.ht
m
>
>

From otto at sover.net Wed May 1 15:58:21 2002
From: otto at sover.net (Jon & Carrol Otto)
Date: Tue Aug 31 21:37:49 2004
Subject: Shell Fdn proposal
Message-ID: <01ce01c1f170$0dcaa4e0$53b772d8@f1v9q1>

Paul, et. al. --

Paul's point about not sharing as much during this Shell RFP period rings
true. As a mainly silent, lurking type of stover anyway, my non-contribution
in recent weeks was hardly noticed.

Still, I will glaldy tell anyone interested that we put in a concept paper
to Shell under our program called ProTREE (Promotion of Technology for
Renewable Energy Enterprises). The funds requested were to further our work
with plant oil (Jatropha curcas) fuel and appliances in Tanzania under the
Health and Household Energy component of the Shell RFP.

We now have a functional prototype stove using Jatropha oil -- a fuel which
seems totally renewable and clean-burining (no emissions testing to support
this latter claim). So the idea is to further develop the energy system
around this liquid fuel -- the energy farms of Jatropha plantings on eroded
or otherwise underused lands that supplement and eventually replace some of
the unsustainable harvesting of woody biomass, and the production/marketing
chain to bring the fuel, cookstove, lamps and manual oilseed press (for oil
extraction) into commercial use.

OK: that's our humble story. Anyone else wanna step forward about your Shell
gambit, and let the 'funding chips' fall where they may?

Jonathan Otto
Pamoja Inc.

-----Original Message-----
From: Paul S. Anderson <psanders@ilstu.edu>
To: Bob and Karla Weldon <bobkarlaweldon@cs.com>; Ed Francis
<cfranc@ilstu.edu>; Tsamba--Alberto Julio <ajtsamba@zebra.uem.mz>; Lily
Coyle <astrozen2000@hotmail.com>; stoves@crest.org <stoves@crest.org>
Date: Wednesday, May 01, 2002 11:44 AM
Subject: Stove efficiency

>Stovers,
>
>First an observation: MUCH less Stoves message traffic in this period of
>application for the Shell Foundation funding. Why: 1) People busy on
>their own applications, and 2) people NOT wanting to share quite so much
>info when the "funding chips" are being discussed, and
>3) people are discussing with smaller groups of closer friends.
>
>Whatever the case, let's keep key issues on the Stoves list.
>
>Here is one: Stove efficiency
>
>Someone on the Stoves list previously stated that the energy output from a
>unit of fuel is always the same if it is completely consumed, and therefore
>the efficiency of the combustion is equal for all stoves that burn
>fully. I believe that is a correct statement.
>
>Therefore, the issues of efficiency are in 3 categories:
>
>A). Issues about getting the combustion to be complete. That is, stoves
>that smoke certainly must be less efficient than those that do not smoke
>(assuming the same fuel).
>
>and
>
>B). Issues of getting the heat into something USEFUL (and that can be
>measured??). I keep remembering the "hay box" that continues to cook with
>the heat that is already present in the hot pot of ingredients, even when
>the stove is off. If we assume that some people would do that, how can
>that be measured as efficiency? Part of this is the question of TIME and
>the control-ability of the amount of combustion at the desired rates when
>needed.
>
>and
>
>C). Cultural (not physical) issues of SOCIAL behavior (cooking practices)
>and ECONOMIC realities (cost of the fuels) that may make the above two (A
>and B) of less consequence. Examples:
>1. Rural primitive cooker (on 3 stones) in a forest with few other people
>and such an abundance of wood available that the thought of saving wood
>would be beyond imagination.
>2. Oven cooking vs "burner-top" cooking in pots vs "food-over-flame"
>cooking (as in meat over an open flame).
>
>
>Stated another way, do we or anybody have functional measurements of
>efficiency (other than how much water is boiled in X time by Y amount of
>fuel Z)?? And is that even important? I believe that it is important,
>but how much effort should we expend on defining and operationalizing some
>measures of efficiency?
>
>Happy 1st of May (a holiday for many of you!!)
>
>Paul
>Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
>Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
>Dept of Geography - Geology (Box 4400), Illinois State University
>Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
>E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders
>
>
>-
>Stoves List Archives and Website:
>http://www.crest.org/discussion/stoves/200204/
>http://crest.org/discussiongroups/resources/stoves/
>>
>Stoves List Moderators:
>Ron Larson, ronallarson@qwest.net
>Elsen L. Karstad, elk@wananchi.com www.chardust.com
>>
>List-Post: <mailto:stoves@crest.org>
>List-Help: <mailto:stoves-help@crest.org>
>List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
>List-Subscribe: <mailto:stoves-subscribe@crest.org>
>>
>Sponsor the Stoves List: http://www.crest.org/discuss3.html
>-
>Other Biomass Stoves Events and Information:
>http://www.bioenergy2002.org
>http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
>http://www.crest.org/articles/static/1/1011975339_7.html Gasification
>http://www.crest.org/articles/static/1/1011975672_7.html Carbon
>>
>For information about CHAMBERS STOVES
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.ht
m
>

From dstill at epud.net Wed May 1 17:12:24 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
Message-ID: <006b01c1f18d$924717e0$fc1d66ce@default>

Dear Stovers,

Very much appreciate Grant's comments on stove efficiency and testing. The
tests that we use, based on the VITA standards, are best when there are
several stoves on the ground in front of you. No test replicates reality
exactly and experimenters are hopefully aware of limitations. But good tests
point out differences so that progress can be made. If folks had bothered to
do more testing we'd be miles ahead today.

Testing the Uganda two pot prototype is interesting. The pot directly on top
of the 4" Rocket combustion chamber is 12" in diameter. About 40% of the
heat is entering this big pot. 6.6 pounds of water boiled in 8 minutes,
today. The second 10" in diameter pot takes in a bit more heat (4.4 pounds
of water reached 150F after burning two pounds of wood) so that exit
temperatures out of the external chimney hover between 80 to 100F. Very low.
The draft created by the internal chimney in the Rocket elbow creates enough
air flow to push flue gases to the bottom of the chimney. The stove operates
but I'm going to open up the gaps to see if efficiency rises or falls with
greater velocity. I know that we'll get better burning but it will be
interesting to see what happens to heat transfer. I can see that we need
more air because the stove is making charcoal.

Today we started adding jets of fan driven air, that enter right above the
burning wood (aimed up the Rocket chimney), trying to improve mixing while
keeping the convenient horizontal feed magazine. Seems to work ok but It
looks like it could stand to have bigger holes or faster air or ?. Does
anyone know the best size for jets of air, best velocity, number of inlets,
etc? Should I bother to preheat the air?

Thanks,

Dean

From lickd at bkk2.loxinfo.co.th Wed May 1 17:29:20 2002
From: lickd at bkk2.loxinfo.co.th (lickd)
Date: Tue Aug 31 21:37:49 2004
Subject: LookNormal
Message-ID: <0GVG00IN2N9O9D@ipop6.tm.net.my>

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From hseaver at cybershamanix.com Wed May 1 18:42:43 2002
From: hseaver at cybershamanix.com (Harmon Seaver)
Date: Tue Aug 31 21:37:49 2004
Subject: Netscape etc
In-Reply-To: <001f01c1f14c$8eb1a5a0$53e80fc4@home>
Message-ID: <20020502034128.GA547@cybershamanix.com>

On Wed, May 01, 2002 at 08:24:37PM +0200, Crispin wrote:
> Dear Harmon
>
> > Of course, people might take notice that you were no longer
> >spreading viruses or sending out messages about what to do
> >to fix the latest one.
>
> Of course that is true, but by a bump on a log means that people turn to me
> to solve many problems and keeping computer systems going - back to XT's (no
> kidding) is part of living a techie's life in Swaziland.

Exactly why you need to shepherd them to the safe fold.

>
> What you say is true aobut Nestcape, I hear you, but if we all went to
> Netscape people would simply move on to writing viruses for Netscape.
>
Tah! Not at all -- the war is against M$, most people who write viruses are
not just mindless vandals.

> When a little more backup for Linux is available around here (about which I
> know nothing at all) and probably after my son the Windows product fundi
> learns a lot about it, I will jump to Corel Office for Linux in one leap and
> dedicate the time necessary to it.
>
> Now that XP is out and they want a bookkeeper's months salary for a copy in
> this country, the pressure is on to change operating systems.
>
>

Ah, now there you go. Or, for people who just can't cut the technical
mustard, what I most always recommend for joe homeuser is a Mac. In fact,
everytime I have to fix some poor soul's windoze box, I always make that
suggestion -- "Wouldn't you really be a lot happier with a Mac?"

--
Harmon Seaver
CyberShamanix
http://www.cybershamanix.com

From rstanley at legacyfound.org Wed May 1 21:06:14 2002
From: rstanley at legacyfound.org (Richard Stanley)
Date: Tue Aug 31 21:37:49 2004
Subject: Nut-hulled pellets for backup heat
In-Reply-To: <002701c1f171$546e5580$9551c5cb@adkarvepn2.vsnl.net.in>
Message-ID: <3CD17103.37E6DC94@legacyfound.org>

And, the fourth alternative is to combine them in a fibrous slurry of agro
residues and compact dewater the mass into briquettes -- a process which
captures all the heat and generates income right at the grass roots without
incurring the aroma of cattle dung or the energy losses of pulverising
and extruding --or charring.
Richard Stanley
www.legacyfound.org

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From brunom1 at yucom.be Thu May 2 00:43:38 2002
From: brunom1 at yucom.be (Bruno M.)
Date: Tue Aug 31 21:37:49 2004
Subject: LookNormal--> CONTAINS VIRUS !!!
In-Reply-To: <0GVG00IN2N9O9D@ipop6.tm.net.my>
Message-ID: <5.1.0.14.0.20020502112559.00a2ad30@pop3.yucom.be>

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From pverhaart at optusnet.com.au Thu May 2 02:31:04 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
In-Reply-To: <006b01c1f18d$924717e0$fc1d66ce@default>
Message-ID: <5.1.0.14.2.20020502211339.00a73ec0@localhost>

Dear Dean,
One
sentence that went right to my heart. It should be there in large bold
print.
At 20:57 1/05/02 -0700, you wrote:
If folks had
bothered to do more testing we'd be miles ahead today.

Testing the Uganda two pot
prototype is interesting. The pot directly on top
of the 4" Rocket combustion chamber is 12" in diameter. About
40% of the
heat is entering this big pot. 6.6 pounds of water boiled in 8
minutes,
today. The second 10" in diameter pot takes in a bit more heat (4.4
pounds
of water reached 150F after burning two pounds of wood) so that
exit
temperatures out of the external chimney hover between 80 to 100F. Very
low.
The draft created by the internal chimney in the Rocket elbow creates
enough
air flow to push flue gases to the bottom of the chimney. The stove
operates
but I'm going to open up the gaps to see if efficiency rises or falls
with
greater velocity. I know that we'll get better burning but it will
be
interesting to see what happens to heat transfer. I can see that we
need
more air because the stove is making charcoal.

It is possible that higher velocities mean more air, which would lower
the temperature.
Today we started adding jets of fan
driven air, that enter right above the
burning wood (aimed up the Rocket chimney), trying to improve mixing
while
keeping the convenient horizontal feed magazine.
So this air does not take part in the combustion but is used in a jet
pump. As it increases the airflow through the fuel, you would get a
higher combustion rate, possibly cleaner combustion but you add a lot of
air to the stove that does not take part in the combustion and dilutes
the hot gases.
Couldn't you blow the air through the fire?
You are doing very important work, happy to be on the list with
you.
Kind regards,
Piet

From psanders at ilstu.edu Thu May 2 05:57:41 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove resources Re: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <4.3.1.2.20020502093224.0189c710@mail.ilstu.edu>

Stovers,

DO NOT MISS THIS INFO ABOUT STOVE EFFICIENCY !!!

In our busy lives we sometimes over look great resources, and then
re-invent the wheel, or make errors that could easily have been avoided.

I call your attention to the Ph.D. thesis of Grant Ballard-Tremeer. If you
have read it cover to cover, then ignore this message because you already
know how important it is. EVERYONE WHO IS SERIOUS ABOUT STOVES ISSUES
SHOULD KNOW WHAT IS IN GRANT'S THESIS.

You do NOT have to agree with him.

But you cannot claim to be an expert without having consulted his thesis !!!

Just the Bibliography is worth its weight in gold. A thesis dated 1997 is
only a very few years out of date. (Suggestion to Grant: How about a
periodic up-date of the bibliography, to be posted on the Internet and
mentioned to the Stoves list?)

And the whole thesis is free (no weight in digital files) at the Internet.
http://ecoharmony.com/thesis

As you all know, I am NOT a heavyweight in the science of stoves. But I am
a university professor who can recognize valuable info.

I am re-sending Grant's recent posting to the Stoves List serve JUST IN
CASE you missed it.

Grant lives in the UK, but the thesis was for Wits Univ. in South
Africa. Perhaps Grant can explain that and tell us a little more about
which place he is from originally. Much info about him and eco LTD is
found at the website that is mentioned in his signature block:
>visit ECO Ltd on the web at http://ecoharmony.com

Grant was one of the people who offered (for a fee) to be available for
stoves testing work relating to a proposed Shell Foundation grant. Others
might be interested in him and his capabilities. (Note: Not a
recommendation pro or con, just a comment. I have not yet done any work
with Grant.)

Paul

At 07:50 PM 5/1/02 +0100, Grant Ballard-Tremeer wrote:
>Hello Stovers,
>
>Wednesday, May 1, 2002, 4:51:57 PM, Paul, when discussing stove
>efficiency wrote:
>PSA> A). Issues about getting the combustion to be complete. That
>PSA> is, stoves that smoke certainly must be less efficient than those
>PSA> that do not smoke (assuming the same fuel).
>
>And, I would add, assuming a number of other things too. I have tested
>many smokey stoves which have *overall* efficiencies higher than less
>smokey stoves - such as those in figure 6 here:
>http://ecoharmony.com/thesis/AppdxE.htm.
>
>The one of the easiest way to increase the heat transfer to the pot is
>to force the flame against the (cold) bottom of the pot. This quenches
>the flame producing smoke and soot, but the loss of efficiency due to
>reduced combustion efficiency is far outweighed by the gain in
>increased heat transfer efficiency. I'm sure you know this already,
>but "stoves that smoke certainly must be less efficient" is not
>entirely true.
>
>PSA> B). Issues of getting the heat into something USEFUL (and that
>PSA> can be measured??).
>
>That's what the measurement of efficiency is all about - the ratio of
>useful work done to energy supplied.
>
>PSA> I keep remembering the "hay box" that continues to cook with the
>PSA> heat that is already present in the hot pot of ingredients, even
>PSA> when the stove is off.
>
>An 'efficiency' measure for hay boxes is not difficult to define in my
>opinion. To compare hay boxes I would use time as an indicator of
>efficiency (time temperature maintained inside the pot above 80°C for
>example). To compare stove-haybox combination a good indicator could
>be energy input per meal prepared (or water brought to the boil and
>maintained above a certain temperature for a predetermined time).
>
>PSA> C). Cultural (not physical) issues of SOCIAL behavior (cooking
>practices)
>PSA> and ECONOMIC realities (cost of the fuels) that may make the above
>two (A
>PSA> and B) of less consequence. Examples:
>PSA> 1. Rural primitive cooker (on 3 stones) in a forest with few other
>people
>PSA> and such an abundance of wood available that the thought of saving wood
>PSA> would be beyond imagination.
>PSA> 2. Oven cooking vs "burner-top" cooking in pots vs "food-over-flame"
>PSA> cooking (as in meat over an open flame).
>
>I have discussed some of these issues at
>http://ecoharmony.com/thesis/AppdxB.htm - I personally do not believe
>that a universal measure of efficiency is useful for comparing stoves.
>I believe that we need testing guidelines which can relate to specific
>socio-cultural practice, and ensure control where it is necessary, but
>are flexible for non-critical factors. This of course means that test
>results are internally comparable.
>
>Volunteers in Technical Assistance (VITA) produced 'International
>Standards' for stove testing in 1985 "Testing the efficiency of
>wood-burning cookstoves" based on extensive consultation, and I
>believe most of it is still highly relevant.
>
>Regards
>Grant
>
>--
>Grant Ballard-Tremeer PhD, visit ECO Ltd on the web at http://ecoharmony.com
>64C Fairholme Road, W14 9JY, London
>Tel +44-(0)20 7386 7930
>Fax +44-(0)870 137 2360 and +44-(0)70 9236 7695
>email stoves@ecoharmony.com
>HEDON Household Energy Network http://ecoharmony.net/hedon
>HEDON on Agenda 21 and the World Summit http://ecoharmony.net/agenda21

Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
Dept of Geography - Geology (Box 4400), Illinois State University
Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders

From d.rl at virgin.net Thu May 2 06:14:07 2002
From: d.rl at virgin.net (David Reynolds-Lacey)
Date: Tue Aug 31 21:37:49 2004
Subject: Much tighter list security required
Message-ID: <3CD15798.6030705@virgin.net>

I posted this to "unsubscribe" some time ago and assumed it would also appear as a post on the list but it didn't I therefore post it again now in order that my comments are noted and my action will be understood.

Dear all,

Yet again, a virus has been posted to the list (Subject: look normal -
Sender: lickd), This should not really be possible if the list
administrators and all posters had effective AV software, I am on
several forums and this is the only one from which I have received
viruses. Even though I have anti-Virus software, updated daily and I
don't use Microsoft's products, I still think the danger is too great -
for example, I wouldn't walk across a live shooting range just because I
was wearing a bullet proof vest!

I fully understand the difficulties faced by some list members in
affording anti-virus software, but you do have to do something positive
to prevent this problem. It has already been suggested that moving to
Netscape (it's free!) or similar would help, you should also remove the
"stoves" address from your address book and enter it in manually each
time you post, but really you should unsubscribe from the list,
remembering (most important) to REMOVE the "stoves" and any list members
address's from your address book until you have taken all possible steps
to protect yourselves and the "list", you will still be able to follow
the list in the archives.

Please, please, understand that I am not advocating a "witch hunt", nor
trying to create bad feeling, but positive action is the only way to
defeat the virus problem, if you don't take the "medication" you WILL
get the disease !

I therefore regret that until the list is made more secure I must
request that I be unsubscribed. I will of course follow activities in
the archive for the time being

Many thanks.

David Reynolds-Lacey

From tombreed at attbi.com Thu May 2 06:29:33 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:49 2004
Subject: Correction of Renewable Energy Technology Software from Canada
Message-ID: <002101c1f1ec$81dd1490$0680fd0c@TOMBREED>

Dear All:

Someone wrote that the link I gave for downloading
the Natural Resources Board of Canada software

<A
href="file:///E:/Medias/www/ang/v2000.html">file:///E:/Medias/www/ang/v2000.html

didn't work. I checked again this morning and
it should have been

E:\Medias\www\ang\v2000.html

which seems to work OK....

TOM REED

----- Original Message -----
From: <A
title=tombreed@attbi.com href="mailto:tombreed@attbi.com">Tom Reed
To: <A title=gasification@crest.org
href="mailto:gasification@crest.org">gasification ; <A
title=Stoves@crest.org href="mailto:Stoves@crest.org">Stoves ; <A
title=bioenergy@crest.org href="mailto:bioenergy@crest.org">bioenergy
Sent: Wednesday, May 01, 2002 3:11 PM
Subject: Renewable Energy Technology Software from
Canada

Dear All:

I recently received in the mail a disc from the
Natural Resources Board of Canada with a lot of software such as
energy model
cost analysis
GHG analysis
Financial Summary
Weather Data
Product Data
Technology Guide
Training Course

I have only looked at it briefly but it seems to be
a useful analysis tool for many things....

Check it out at
<A
href="file:///E:/Medias/www/ang/v2000.html">file:///E:/Medias/www/ang/v2000.html
E:\Medias\www\ang\v2000.html

The focus seems to be particularly strong on wind,
but there are links to all other energy technologies as well.

Yours
truly,
TOM
REED
BEF

From tombreed at attbi.com Thu May 2 06:51:00 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:49 2004
Subject: Grrr... Correction of "correction to Renewable Energy Technology Software from Canada"
Message-ID: <004a01c1f1ee$6f549850$0680fd0c@TOMBREED>

Dear All:

Forget my last correction (always read mail top
down).. I must have been giving internal links on the CD I had.

On the web go to

<A
href="http://retscreen.gc.ca">http://retscreen.gc.ca

to download the Energy Software from
Canada.

Sorry..

TOM REED

From psanders at ilstu.edu Thu May 2 11:56:29 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <4.3.1.2.20020502152728.018a6410@mail.ilstu.edu>

Stovers (and maybe for an ETHOS specialist),

At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:

>Yes but the difference [between a stove that smokes and one that does not]
>could be minimal. This even inspired an Eindhoven professor to state that
>combustion efficiency was not worth pursuing in cookstove research.

Can you or anyone provide a "quotable quote" with full reference for such a
statement, by that professor or anyone else?

Because, judging by the responses about this topic, COMBUSTION efficiency
might not be of much concern at all. Because:

1. The burning produces the energy, but it is the people and their actions
that really influence efficiency.

2. In the 4-part characterization of "stoves" (being fuel, combustion
chamber, structure around the combustion chamber - top, sides, etc, and
cooking practices), the first 2 are being declared of "lesser importance"
for efficiency, and the last 2 are where the efficiency issues are
important (or are at least strongly influenced.)

3. Therefore, Juntos gasifier and Rocket and any other
"combustion-chamber-focused" stove are all about the same AS FAR AS
COMBUSTION EFFICIENCY IS CONCERNED.

4. But the structures around Juntos or Rocket or many other combustion
chambers ARE important for efficiency. (Is anyone working on "structure"
as being separate from the combustion chamber? Is there a "plancha"
specialist in the audience -- who is not married to one of the specific
combustion chamber modes?)

5. And do not forget the "cooking practices" variable, which is less
quantitatively scientific and is more subjective and social, and heavily
influences the efficiency of any "cooking station" (with fuel, combustion
chamber, and structure, as well as cooking practices).

6. Therefore, in contrast with "COMBUSTION efficiency", can we have
a concept like "heat-CAPTURE efficiency"?

Please do not forget:
Can you or anyone provide a "quotable quote" with full reference for such a
statement about combustion efficiency NOT meriting attention for small
stove research or concern, by that professor or anyone else?

Or maybe YOU want to provide such a statement to the Stoves list with the
intention that the rest of us can quote YOU as stating that "combustion
efficiency" (as clearly defined by YOU) is not sufficiently important to
merit much attention.

P.S. I hope you do not think that I am just rambling on about
nothing. (If so, please tell me so I know to stop.) I have been learning
from the messages, and clearly not everyone shares the same thoughts. I am
just trying to bring pieces of information together for clear understanding.

Smile,

From jmdavies at xsinet.co.za Thu May 2 13:58:18 2002
From: jmdavies at xsinet.co.za (John Davies)
Date: Tue Aug 31 21:37:49 2004
Subject: Klez Virus.
In-Reply-To: <5.1.0.14.0.20020502112559.00a2ad30@pop3.yucom.be>
Message-ID: <00c301c1f22d$b27ef780$026a27c4@jmdavies>

Bruno wrote;
----- Original Message -----
From: Bruno M. <brunom1@yucom.be>
To: <stoves@crest.org>
Sent: Thursday, May 02, 2002 11:41 AM
Subject: Re: LookNormal--> CONTAINS VIRUS !!!

> At 09:39 02/05/2002 +0800, you wrote:
>
>
> ============================================================
>
> I received AGAIN a (empty) message from the stoves list with
> with a virus attached !!!!!!!!
> " Apperently" it was sent by : lickd <lickd@bkk2.loxinfo.co.th>
> The attachments were called: " title.exe " and "NavBar[1].htm"
> The first one is the virus; it is the " Win.32.Klez.H" virus.
> This is a very nasty "wormvirus".
> So dear fellow listmembers : DON't open those attachments,
> delete them and update your antivirus software.

I am receiving almost daily a variant of this virus " Win 32 Kletz. gen@MM "

this is the first received that activates without opening the attachment.
It has a garbled senders name and several different subject lines, so it
looks like a virus.
The only problem is that as soon as you highlight the message line to delete
it, it writes a file in the temporary file folder\older.
Fortunately an up to date "McAfee" detects this right away. and the file can
be deleted as soon as it is written and hopefully before it causes problems.

This appears to be a new generation of VIRUSES. _ BE WARNED.

After each attempted infection I have scanned my whole system, and receive a
clean report.

Regards,
John Davies.

From brunom1 at yucom.be Thu May 2 17:06:18 2002
From: brunom1 at yucom.be (Bruno M.)
Date: Tue Aug 31 21:37:49 2004
Subject: Klez Virus.
In-Reply-To: <5.1.0.14.0.20020502112559.00a2ad30@pop3.yucom.be>
Message-ID: <5.1.0.14.0.20020503025536.00a1fdc0@pop3.yucom.be>

At 22:46 02/05/2002 +0200, John Davies wrote:
>Bruno wrote;
>----- Original Message -----
>From: Bruno M. <brunom1@yucom.be>
>To: <stoves@crest.org>
>Sent: Thursday, May 02, 2002 11:41 AM
>Subject: Re: LookNormal--> CONTAINS VIRUS !!!
> > At 09:39 02/05/2002 +0800, you wrote:
> > ============================================================
> > I received AGAIN a (empty) message from the stoves list with
> > with a virus attached !!!!!!!!
> > " Apperently" it was sent by : lickd <lickd@bkk2.loxinfo.co.th>
> > The attachments were called: " title.exe " and "NavBar[1].htm"
> > The first one is the virus; it is the " Win.32.Klez.H" virus.
> > This is a very nasty "wormvirus".
> > So dear fellow listmembers : DON't open those attachments,
> > delete them and update your antivirus software.
>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>I am receiving almost daily a variant of this virus " Win 32 Kletz. gen@MM "
>this is the first received that activates without opening the attachment.
>It has a garbled senders name and several different subject lines, so it
>looks like a virus.
>The only problem is that as soon as you highlight the message line to delete
>it, it writes a file in the temporary file folder\older.
>Fortunately an up to date "McAfee" detects this right away. and the file can
>be deleted as soon as it is written and hopefully before it causes problems.
>This appears to be a new generation of VIRUSES. _ BE WARNED.
>After each attempted infection I have scanned my whole system, and receive a
>clean report.
>Regards,
>John Davies.
==========================================================
Dear John and list members,
I know that this virus stuff is off-topic, but, since from the
25 lists I'm on, only the crest's lists keep sending me a
weekly load of viruses, and some members said they don't
have the means for up-to-date anti virus-software, i like to trow
an other 3 cents in.
What John said is write for the H variety of this Klez worm,
and for users of outlook and outlook express.
I can't solve all the virus problems of this list; but for those
who like to act against the "worm of the week", i found a
nice link, including some free software to get this one off your system.
A professional explanation and some help ( read it until the bottom line,
the 2 links on the bottom are the one you need ):
http://www.europe.f-secure.com/v-descs/klez.shtml
If there are members that have no access to that site ( only email)
they can mail me direct. I like to help them, to forward them a small 32K
zip file
( manual included ! ) containing the tool to remove this bastard.
And further I'm not the first one to advice you to drop outlook-virus-magnet;
use Eudora Pro 5.1 http://www.eudora.com/ ( also free=ad ware) instead,
or others...take your pick. Instead of Internet Explorer from M.§oft, surf
with Opera 6.0
http://www.opera.com/ ( even for linux and mac) or netscape, or... .for free !
Use uptodated AV soft, also available for free ( free and shareware).
You can't live without outlook and IE 5.01? Then update it at least with:
http://www.microsoft.com/windows/ie/downloads/critical/q290108/default.asp
What I wanna say is : if you take some time
it even cost no dime :-)
And let's pray with me, that the list-owner can keep the lists clean in the
future ! ;-)
Hope this was of any help to the members.
Greetings
Bruno M.
( who have no connection with the named products, just a happy user )
------------------------------

Reply's to BrunoM1@yucom.be

From kimhok00 at tm.net.my Thu May 2 17:18:01 2002
From: kimhok00 at tm.net.my (kimhok00)
Date: Tue Aug 31 21:37:49 2004
Subject: VISIBILITY
Message-ID: <0GVI00099JBZ7T@ipop1.tm.net.my>

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From E.KITUYI at CGIAR.ORG Thu May 2 22:18:32 2002
From: E.KITUYI at CGIAR.ORG (Kituyi, Evans)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove resources Re: Stove efficiency
Message-ID: <FC788AB9771FD6118E6F0002A5AD7B8F5CD7C3@icrafnttrain.icraf.cgiar.org>

There are lots of other student theses out here too, on various aspects of
stoves. Perhaps we need to have a system of locating and documenting these
important contributions. I have also had a chance to read Grant's thesis and
subsequent publications in Elsevier's Biomass & Bioenergy journal. Thanks

Evans

-----Original Message-----
From: Paul S. Anderson [mailto:psanders@ilstu.edu]
Sent: Thursday, May 02, 2002 6:06 PM
To: Grant Ballard-Tremeer; stoves@crest.org
Cc: Bob and Karla Weldon; Ed Francis; Tsamba--Alberto Julio; Lily Coyle
Subject: Stove resources Re: Stove efficiency

Stovers,

DO NOT MISS THIS INFO ABOUT STOVE EFFICIENCY !!!

In our busy lives we sometimes over look great resources, and then
re-invent the wheel, or make errors that could easily have been avoided.

You do NOT have to agree with him.

But you cannot claim to be an expert without having consulted his thesis !!!

And the whole thesis is free (no weight in digital files) at the Internet.
http://ecoharmony.com/thesis

As you all know, I am NOT a heavyweight in the science of stoves. But I am
a university professor who can recognize valuable info.

I am re-sending Grant's recent posting to the Stoves List serve JUST IN
CASE you missed it.

Paul

At 07:50 PM 5/1/02 +0100, Grant Ballard-Tremeer wrote:
>Hello Stovers,
>
>Wednesday, May 1, 2002, 4:51:57 PM, Paul, when discussing stove
>efficiency wrote:
>PSA> A). Issues about getting the combustion to be complete. That
>PSA> is, stoves that smoke certainly must be less efficient than those
>PSA> that do not smoke (assuming the same fuel).
>
>And, I would add, assuming a number of other things too. I have tested
>many smokey stoves which have *overall* efficiencies higher than less
>smokey stoves - such as those in figure 6 here:
>http://ecoharmony.com/thesis/AppdxE.htm.
>
>The one of the easiest way to increase the heat transfer to the pot is
>to force the flame against the (cold) bottom of the pot. This quenches
>the flame producing smoke and soot, but the loss of efficiency due to
>reduced combustion efficiency is far outweighed by the gain in
>increased heat transfer efficiency. I'm sure you know this already,
>but "stoves that smoke certainly must be less efficient" is not
>entirely true.
>
>PSA> B). Issues of getting the heat into something USEFUL (and that
>PSA> can be measured??).
>
>That's what the measurement of efficiency is all about - the ratio of
>useful work done to energy supplied.
>
>PSA> I keep remembering the "hay box" that continues to cook with the
>PSA> heat that is already present in the hot pot of ingredients, even
>PSA> when the stove is off.
>
>An 'efficiency' measure for hay boxes is not difficult to define in my
>opinion. To compare hay boxes I would use time as an indicator of
>efficiency (time temperature maintained inside the pot above 80°C for
>example). To compare stove-haybox combination a good indicator could
>be energy input per meal prepared (or water brought to the boil and
>maintained above a certain temperature for a predetermined time).
>
>PSA> C). Cultural (not physical) issues of SOCIAL behavior (cooking
>practices)
>PSA> and ECONOMIC realities (cost of the fuels) that may make the above
>two (A
>PSA> and B) of less consequence. Examples:
>PSA> 1. Rural primitive cooker (on 3 stones) in a forest with few other
>people
>PSA> and such an abundance of wood available that the thought of saving
wood
>PSA> would be beyond imagination.
>PSA> 2. Oven cooking vs "burner-top" cooking in pots vs "food-over-flame"
>PSA> cooking (as in meat over an open flame).
>
>I have discussed some of these issues at
>http://ecoharmony.com/thesis/AppdxB.htm - I personally do not believe
>that a universal measure of efficiency is useful for comparing stoves.
>I believe that we need testing guidelines which can relate to specific
>socio-cultural practice, and ensure control where it is necessary, but
>are flexible for non-critical factors. This of course means that test
>results are internally comparable.
>
>Volunteers in Technical Assistance (VITA) produced 'International
>Standards' for stove testing in 1985 "Testing the efficiency of
>wood-burning cookstoves" based on extensive consultation, and I
>believe most of it is still highly relevant.
>
>Regards
>Grant
>
>--
>Grant Ballard-Tremeer PhD, visit ECO Ltd on the web at
http://ecoharmony.com
>64C Fairholme Road, W14 9JY, London
>Tel +44-(0)20 7386 7930
>Fax +44-(0)870 137 2360 and +44-(0)70 9236 7695
>email stoves@ecoharmony.com
>HEDON Household Energy Network http://ecoharmony.net/hedon
>HEDON on Agenda 21 and the World Summit http://ecoharmony.net/agenda21

From crispin at newdawn.sz Thu May 2 22:46:06 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:49 2004
Subject: LookNormal--> CONTAINS VIRUS !!!
Message-ID: <006601c1f277$4e4ec660$2a47fea9@md>

Dear Bruno

The Klez set of worms can generate false "from' names, as
Elk found out. I see that the size can vary from 130 to 170K as
well.

Regards
Crispin

From crispin at newdawn.sz Thu May 2 22:46:50 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
Message-ID: <006701c1f277$4f076800$2a47fea9@md>

Dear Dean

>The second 10" in diameter pot takes in a bit more heat (4.4 pounds
>of water reached 150F after burning two pounds of wood) so that exit
>temperatures out of the external chimney hover between 80 to 100F.

While clearly this is capturing heat, there is a very important thing that
is missing - hot exit gases. It is not wise to let the exit temperature of
the stack drop below 150C because H2SO3 will condense and run down inside
chowing right through the steelwork in a matter of weeks or months. That is
why the stacks of rural households here are always full of holes. They burn
wood, choked for air, at low temperatures in coal stoves. Try to get the
stack temp up to 165C to avoid corrosion.

The stack temp of our little baking oven hovers miraculously between 165 and
230 depending on the power being used, but that was more by fluke than by
design.

Regards
Crispin

From andrew.heggie at dtn.ntl.com Fri May 3 00:42:19 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:49 2004
Subject: Klez Virus.
In-Reply-To: <5.1.0.14.0.20020502112559.00a2ad30@pop3.yucom.be>
Message-ID: <dvj4du899ddc76s6l9if32eihfb5mlbir6@4ax.com>

On Fri, 03 May 2002 04:04:32 +0200, "Bruno M." <brunom1@yucom.be>
wrote:

>And further I'm not the first one to advice you to drop outlook-virus-magnet;
>use Eudora Pro 5.1 http://www.eudora.com/

I agree with Bruno on this, I believe Eudora lite is still freeware as
is Pegasus. Opera 6 is free with a small inconspicuous ad pane but
some M$ based sites dependant on cookies will not work, but by this
very nature mean they are best avoided. If you should wish to see
usenet FreeAgent is again freeware.

Zonealarm is a free "firewall" which can be set to deny access to
outlook so outlook's other (non-internet) features can be used, it
will also quarantine suspect attachments.

>And let's pray with me, that the list-owner can keep the lists clean in the
>future ! ;-)

Porcine aviators? ;-)

AJH

From andrew.heggie at dtn.ntl.com Fri May 3 00:43:09 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:49 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <luk4du4vjamngm42k9kc5eaoj4i62qbdo7@4ax.com>

On Wed, 1 May 2002 19:50:35 +0100, Grant Ballard-Tremeer
<stoves@ecoharmony.com> wrote:

>
>The one of the easiest way to increase the heat transfer to the pot is
>to force the flame against the (cold) bottom of the pot.

I can see this being true over an open fire or a stove which has a lot
of heat loss through the sides, is it necessarily true in all cases?
Is there something about the action of the flame (e.g. is it more
effective at scrubbing off the boundary layer) which completely
reacted flue gases lack?

> This quenches
>the flame producing smoke and soot, but the loss of efficiency due to
>reduced combustion efficiency is far outweighed by the gain in
>increased heat transfer efficiency. I'm sure you know this already,
>but "stoves that smoke certainly must be less efficient" is not
>entirely true.

This is similar to Dean's reasoning, however I think the prime aim of
stoves development is the health issue, so clean burning is of primary
importance.

I think there is a corollary in IC engine use, it is possible to run a
richer mixture (or higher fueling in CI engines) with resulting more
power, the cost is reduced economy, high CO in the exhaust (or soot in
the case of the CI engine).
AJH

From stoves at ecoharmony.com Fri May 3 01:43:43 2002
From: stoves at ecoharmony.com (Grant Ballard-Tremeer)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove resources Re: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <1433555718.20020503114359@ecoharmony.com>

Hello Paul and Stovers,

PSA> I call your attention to the Ph.D. thesis of Grant Ballard-Tremeer. If you
PSA> have read it cover to cover, then ignore this message because you already
PSA> know how important it is. EVERYONE WHO IS SERIOUS ABOUT STOVES ISSUES
PSA> SHOULD KNOW WHAT IS IN GRANT'S THESIS.

Wow - thanks very much for the endorsement. I'm really grateful for
the positive feedback. I first joined the stoves list back in 1996/7
and have periodically participated in discussions whenever possible,
and I have mentioned my thesis a few times - so some stovers have
heard and looked.

PSA> Just the Bibliography is worth its weight in gold. A thesis dated 1997 is
PSA> only a very few years out of date. (Suggestion to Grant: How about a
PSA> periodic up-date of the bibliography, to be posted on the Internet and
PSA> mentioned to the Stoves list?)

I'm currently working on a project called SPARKNET which will have an
extensive and up-to-date online bibliography. The website is to go
live in the next couple of weeks, and I'll be sure to let 'stoves'
know when it's available.

PSA> And the whole thesis is free (no weight in digital files) at the
PSA> Internet. http://ecoharmony.com/thesis

I can provide a PDF for those that don't want to read online, but it's
a 950KB download. Let me know, and if there is any demand I'll make a
link to it from http://ecoharmony.com/thesis

Paul asked for a little background - I am indeed from South Africa,
but currently based in London since about half my work is carried out
the Eastern Europe and the other half in the Southern Hemisphere (I do
both modern and traditional biomass projects).

Evans Kituyi mentioned that there are other dissertations and theses.
The HEDON Household Energy Network, which I am actively involved in,
has a resource portal at http://ecoharmony.net/hedon/portal.php which
is the ideal place to find (and publicize) such documents. It
currently has 186 relevant links - not many theses and some more
useful than others and it's easy to carry out a search. If you have a
link to useful documents that aren't already there, please submit them
to the site (just click on submit and fill in the simple data).

On the virus question (for anyone who has persevered this far into the
message), I strongly recommend that CREST set the list to remove all
attachments automatically. If attachments are absolutely necessary the
list could perhaps be set to send any messages with attachments to the
moderator for prior approval (and inoculation) before distribution. My
two cents worth.

All the best, happy stove-ing, and thanks again for the compliments.
Grant

--
Grant Ballard-Tremeer PhD, visit ECO Ltd on the web at http://ecoharmony.com
64C Fairholme Road, W14 9JY, London
Tel +44-(0)20 7386 7930
Fax +44-(0)870 137 2360 and +44-(0)70 9236 7695
email grant@ecoharmony.com
HEDON Household Energy Network http://ecoharmony.net/hedon
HEDON on Agenda 21 and the World Summit http://ecoharmony.net/agenda21
-------------------

From pverhaart at optusnet.com.au Fri May 3 03:07:51 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <5.1.0.14.2.20020502113726.00a79d40@mail.optusnet.com.au>
Message-ID: <5.1.0.14.2.20020503213845.00a371c0@localhost>

At 16:04 2/05/02 -0500, you wrote:
>Stovers (and maybe for an ETHOS specialist),
>
>At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:
>
>>Yes but the difference [between a stove that smokes and one that does
>>not] could be minimal. This even inspired an Eindhoven professor to state
>>that combustion efficiency was not worth pursuing in cookstove research.
>
>Can you or anyone provide a "quotable quote" with full reference for such
>a statement, by that professor or anyone else?

It was said in a meeting and was not recorded. In a very narrow sense the
man was right. If maximum heat transfer is the goal, then concentrate on
convection and damn the smoke.
Since I was looking for a way to burn wood with blue flames, I violently
disagreed. This was in early 1980.
I am still looking.

>Because, judging by the responses about this topic, COMBUSTION efficiency
>might not be of much concern at all.

It is because, thankfully and in contrast to the early 80's, we now care
about the emissions.

>3. Therefore, Juntos gasifier and Rocket and any other
>"combustion-chamber-focused" stove are all about the same AS FAR AS
>COMBUSTION EFFICIENCY IS CONCERNED.

If combustion efficiency is defined as: (thermal energy produced/
combustion value), then a similar figure for different stoves would roughly
qualify them as equally polluting.

>4. But the structures around Juntos or Rocket or many other combustion
>chambers ARE important for efficiency. (Is anyone working on "structure"
>as being separate from the combustion chamber? Is there a "plancha"
>specialist in the audience -- who is not married to one of the specific
>combustion chamber modes?)

For stoves that have no open or hidden agenda to produce charcoal as a
fringe benefit, the combustion chambers of the Rocket or the Downdraft
stove provide optimal conditions for complete combustion. Downstream from
the combustion chamber, structure is important to insure optimal heat
transfer to the food being processed (via whatever medium, be it griddle,
pan or oven). As soon as a better combustion chamber is discovered, I will
divorce the Downdraft stove.

>5. And do not forget the "cooking practices" variable, which is less
>quantitatively scientific and is more subjective and social, and heavily
>influences the efficiency of any "cooking station" (with fuel, combustion
>chamber, and structure, as well as cooking practices).

A good and versatile wood burning cookstove should be able to accomodate a
large range of cooking practices. People in the industrialised world have
to make do with standard mass produced gas or electric cookstoves and don't
seem to have much of a problem. The sticking point is "A good and versatile
woodburning cookstove". At the moment there aint no such animal.

>6. Therefore, in contrast with "COMBUSTION efficiency", can we have
>a concept like "heat-CAPTURE efficiency"?
>
>Please do not forget:
>Can you or anyone provide a "quotable quote" with full reference for such
>a statement about combustion efficiency NOT meriting attention for small
>stove research or concern, by that professor or anyone else?

Such a quote should be ignored or used to shoot or at least fire that person.

>Or maybe YOU want to provide such a statement to the Stoves list with the
>intention that the rest of us can quote YOU as stating that "combustion
>efficiency" (as clearly defined by YOU) is not sufficiently important to
>merit much attention.

I think I have clarified the matter.

Smiling back,

Piet

From koopmans at loxinfo.co.th Fri May 3 03:34:47 2002
From: koopmans at loxinfo.co.th (Auke Koopmans)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove resources Re: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <003301c1f29f$5a887a20$c78992cb@xxxx>

You can also have a look at the RWEDP website which has also
some documents on stoves in general, Chinese stoves and Indian stoves. the
website is http://www.rwedp.org under
Publications - Utilization.
However, as RWEDP has been terminated, the website has not
been updated lately. We are working on an update of the database though and
hopefully (time permitting) within a month or so the updated data will be made
available.

Regards,

Auke Koopmans

<BLOCKQUOTE
style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px; PADDING-RIGHT: 0px">
----- Original Message -----
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black">From:
Grant
Ballard-Tremeer
To: <A href="mailto:psanders@ilstu.edu"
title=psanders@ilstu.edu>Paul S. Anderson
Cc: <A href="mailto:stoves@crest.org"
title=stoves@crest.org>stoves@crest.org ; <A
href="mailto:bobkarlaweldon@cs.com" title=bobkarlaweldon@cs.com>Bob and Karla
Weldon ; Ed
Francis ; <A href="mailto:ajtsamba@zebra.uem.mz"
title=ajtsamba@zebra.uem.mz>Tsamba--Alberto Julio ; <A
href="mailto:astrozen2000@hotmail.com" title=astrozen2000@hotmail.com>Lily
Coyle
Sent: 03 May 2002 17:43
Subject: Re: Stove resources Re: Stove
efficiency
Hello Paul and Stovers,PSA> I call your attention to
the Ph.D. thesis of Grant Ballard-Tremeer. If youPSA> have read
it cover to cover, then ignore this message because you already PSA>
know how important it is. EVERYONE WHO IS SERIOUS ABOUT STOVES ISSUES
PSA> SHOULD KNOW WHAT IS IN GRANT'S THESIS.Wow - thanks very
much for the endorsement. I'm really grateful forthe positive feedback. I
first joined the stoves list back in 1996/7and have periodically
participated in discussions whenever possible,and I have mentioned my
thesis a few times - so some stovers haveheard and looked.PSA>
Just the Bibliography is worth its weight in gold. A thesis dated 1997
isPSA> only a very few years out of date. (Suggestion to
Grant: How about a PSA> periodic up-date of the bibliography, to
be posted on the Internet and PSA> mentioned to the Stoves
list?)I'm currently working on a project called SPARKNET which will
have anextensive and up-to-date online bibliography. The website is to
golive in the next couple of weeks, and I'll be sure to let
'stoves'know when it's available.PSA> And the whole thesis is
free (no weight in digital files) at thePSA> Internet. <A
href="http://ecoharmony.com/thesis">http://ecoharmony.com/thesisI
can provide a PDF for those that don't want to read online, but it'sa
950KB download. Let me know, and if there is any demand I'll make alink to
it from <A
href="http://ecoharmony.com/thesis">http://ecoharmony.com/thesisPaul
asked for a little background - I am indeed from South Africa,but
currently based in London since about half my work is carried outthe
Eastern Europe and the other half in the Southern Hemisphere (I doboth
modern and traditional biomass projects).Evans Kituyi mentioned that
there are other dissertations and theses.The HEDON Household Energy
Network, which I am actively involved in,has a resource portal at <A
href="http://ecoharmony.net/hedon/portal.php">http://ecoharmony.net/hedon/portal.php
whichis the ideal place to find (and publicize) such documents.
Itcurrently has 186 relevant links - not many theses and some
moreuseful than others and it's easy to carry out a search. If you have
alink to useful documents that aren't already there, please submit
themto the site (just click on submit and fill in the simple
data).On the virus question (for anyone who has persevered this far
into themessage), I strongly recommend that CREST set the list to remove
allattachments automatically. If attachments are absolutely necessary
thelist could perhaps be set to send any messages with attachments to
themoderator for prior approval (and inoculation) before distribution.
Mytwo cents worth.All the best, happy stove-ing, and thanks again
for the compliments.Grant-- Grant Ballard-Tremeer PhD, visit
ECO Ltd on the web at <A
href="http://ecoharmony.com">http://ecoharmony.com64C Fairholme Road,
W14 9JY, LondonTel +44-(0)20 7386 7930Fax +44-(0)870 137 2360 and
+44-(0)70 9236 7695email <A
href="mailto:grant@ecoharmony.com">grant@ecoharmony.comHEDON Household
Energy Network <A
href="http://ecoharmony.net/hedon">http://ecoharmony.net/hedonHEDON on
Agenda 21 and the World Summit <A
href="http://ecoharmony.net/agenda21">http://ecoharmony.net/agenda21--------------------Stoves
List Archives and Website:<A
href="http://www.crest.org/discussion/stoves/200204/">http://www.crest.org/discussion/stoves/200204/<A
href="http://crest.org/discussiongroups/resources/stoves/">http://crest.org/discussiongroups/resources/stoves/>Stoves
List Moderators:Ron Larson, <A
href="mailto:ronallarson@qwest.net">ronallarson@qwest.netElsen L.
Karstad, elk@wananchi.com <A
href="http://www.chardust.com">www.chardust.com>List-Post:
<<A
href="mailto:stoves@crest.org">mailto:stoves@crest.org>List-Help:
<<A
href="mailto:stoves-help@crest.org">mailto:stoves-help@crest.org>List-Unsubscribe:
<<A
href="mailto:stoves-unsubscribe@crest.org">mailto:stoves-unsubscribe@crest.org>List-Subscribe:
<<A
href="mailto:stoves-subscribe@crest.org">mailto:stoves-subscribe@crest.org>>Sponsor
the Stoves List: <A
href="http://www.crest.org/discuss3.html">http://www.crest.org/discuss3.html-Other
Biomass Stoves Events and Information:<A
href="http://www.bioenergy2002.org">http://www.bioenergy2002.org<A
href="http://www.crest.org/articles/static/1/1010424940_7.html">http://www.crest.org/articles/static/1/1010424940_7.html
Bioenergy<A
href="http://www.crest.org/articles/static/1/1011975339_7.html">http://www.crest.org/articles/static/1/1011975339_7.html
Gasification<A
href="http://www.crest.org/articles/static/1/1011975672_7.html">http://www.crest.org/articles/static/1/1011975672_7.html
Carbon>For information about CHAMBERS STOVES><A
href="http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm">http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm

From tombreed at attbi.com Fri May 3 03:45:21 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:50 2004
Subject: High efficiency and low emissions can reinforce each other.
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <001701c1f29d$04c485e0$0680fd0c@TOMBREED>

Dear Stovers and all:

Note that with a propane or natural gas stove you can simultaneously have
both high efficiency and low emissions. (It is my impression that the
efficiency of gas cooking is well over 40%. (Electric cooking can be 60%,
but with power generation and distribution this drops to 15%). )

Likewise with our "WoodGas" stoves.

Note that in propane or natural gas stoves you need

o A Supply of gas at a controlled pressure (typically 10 iwp)

o A Venturi to mix the gas with controlled amount of air

o A flame holder and shaper

o A grate that holds the pot ~ 20 mm away from the flame holder, giving
the flame a chance to burn completely before being quenched on the pot
surface.

Our natural gas convection stove (below) is an attempt to do the same with
woodgas and we are still making improvements.

This was "state of the art" in 1997. Paul Anderson and others have been
working on it since. High efficiency and low emissions reinforce each
other, so we should not abandon that as an aim.

Yours truly, TOM REED BEF STOVEWORKS

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From rmiranda at sdnnic.org.ni Fri May 3 15:37:24 2002
From: rmiranda at sdnnic.org.ni (Rogerio Miranda)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020502152728.018a6410@mail.ilstu.edu>
Message-ID: <3.0.5.32.20020503182403.00b31e50@205.218.248.130>

Hello:

Just to let you know that influenced by Kirk Smith publications, we PROLEÑA
began work toward an indoor smokeless stove in 1995 in Honduras. First
we introduce the plancha to a lorena stove, which women liked very much due
its clean feature, however the efficiency suffered a lot.

Thanks to Hurricane Mitch in Honduras (that is the only positive side of
the hurricane I can see), Trees Water and People dispatched Aprovecho
volunteers to honduras to promote rocket stoves, including the master Larry
Winiarsky. From their good work, they combined PROLEÑA´s clean but
unefficient plancha stove with the great efficient rocket stove burner. The
result was a tremendous stove called Justa Stove, with no indoor air
pollution and 50% less fuelwood consumption in comparation to the plancha
stove. Furthermore it is a multitask stove. you can cook in small pots, in
a big pot or cook directly on the plancha. Women in Honduras and Nicaragia
just love it.

here in Nicaragua we PROLEÑA decide to make this stove portable and
commercial and we called it the Ecostove. so today we have a manufacture
plant pumping out about 100 Ecosotves per month to a free market demand.
The ecostove has efficiency of about 20% and properly operate has zero
indoor air pollution, besides allowing multiples cooking tasks. For those
interested I will be happy to provide a picture, while our web page is
under construction.

The Ecostove I would say is quite simiar to Piet down draft barbecue.

Best wishes

rogerio

At 10:06 p.m. 03/05/02 +1000, Peter Verhaart wrote:
>At 16:04 2/05/02 -0500, you wrote:
>>Stovers (and maybe for an ETHOS specialist),
>>
>>At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:
>>
>>>Yes but the difference [between a stove that smokes and one that does
>>>not] could be minimal. This even inspired an Eindhoven professor to state
>>>that combustion efficiency was not worth pursuing in cookstove research.
>>
>>Can you or anyone provide a "quotable quote" with full reference for such
>>a statement, by that professor or anyone else?
>
>It was said in a meeting and was not recorded. In a very narrow sense the
>man was right. If maximum heat transfer is the goal, then concentrate on
>convection and damn the smoke.
>Since I was looking for a way to burn wood with blue flames, I violently
>disagreed. This was in early 1980.
>I am still looking.
>
>
>>Because, judging by the responses about this topic, COMBUSTION efficiency
>>might not be of much concern at all.
>
>It is because, thankfully and in contrast to the early 80's, we now care
>about the emissions.
>
>
>>3. Therefore, Juntos gasifier and Rocket and any other
>>"combustion-chamber-focused" stove are all about the same AS FAR AS
>>COMBUSTION EFFICIENCY IS CONCERNED.
>
>If combustion efficiency is defined as: (thermal energy produced/
>combustion value), then a similar figure for different stoves would roughly
>qualify them as equally polluting.
>
>>4. But the structures around Juntos or Rocket or many other combustion
>>chambers ARE important for efficiency. (Is anyone working on "structure"
>>as being separate from the combustion chamber? Is there a "plancha"
>>specialist in the audience -- who is not married to one of the specific
>>combustion chamber modes?)
>
>For stoves that have no open or hidden agenda to produce charcoal as a
>fringe benefit, the combustion chambers of the Rocket or the Downdraft
>stove provide optimal conditions for complete combustion. Downstream from
>the combustion chamber, structure is important to insure optimal heat
>transfer to the food being processed (via whatever medium, be it griddle,
>pan or oven). As soon as a better combustion chamber is discovered, I will
>divorce the Downdraft stove.
>
>>5. And do not forget the "cooking practices" variable, which is less
>>quantitatively scientific and is more subjective and social, and heavily
>>influences the efficiency of any "cooking station" (with fuel, combustion
>>chamber, and structure, as well as cooking practices).
>
>A good and versatile wood burning cookstove should be able to accomodate a
>large range of cooking practices. People in the industrialised world have
>to make do with standard mass produced gas or electric cookstoves and don't
>seem to have much of a problem. The sticking point is "A good and versatile
>woodburning cookstove". At the moment there aint no such animal.
>
>>6. Therefore, in contrast with "COMBUSTION efficiency", can we have
>>a concept like "heat-CAPTURE efficiency"?
>>
>>Please do not forget:
>>Can you or anyone provide a "quotable quote" with full reference for such
>>a statement about combustion efficiency NOT meriting attention for small
>>stove research or concern, by that professor or anyone else?
>
>Such a quote should be ignored or used to shoot or at least fire that person.
>
>>Or maybe YOU want to provide such a statement to the Stoves list with the
>>intention that the rest of us can quote YOU as stating that "combustion
>>efficiency" (as clearly defined by YOU) is not sufficiently important to
>>merit much attention.
>
>I think I have clarified the matter.
>
>Smiling back,
>
>Piet
>
>
>-
>Stoves List Archives and Website:
>http://www.crest.org/discussion/stoves/200204/
>http://crest.org/discussiongroups/resources/stoves/
>>
>Stoves List Moderators:
>Ron Larson, ronallarson@qwest.net
>Elsen L. Karstad, elk@wananchi.com www.chardust.com
>>
>List-Post: <mailto:stoves@crest.org>
>List-Help: <mailto:stoves-help@crest.org>
>List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
>List-Subscribe: <mailto:stoves-subscribe@crest.org>
>>
>Sponsor the Stoves List: http://www.crest.org/discuss3.html
>-
>Other Biomass Stoves Events and Information:
>http://www.bioenergy2002.org
>http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
>http://www.crest.org/articles/static/1/1011975339_7.html Gasification
>http://www.crest.org/articles/static/1/1011975672_7.html Carbon
>>
>For information about CHAMBERS STOVES
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Rogério Carneiro de Miranda
Director, Ecofogones y Reposición Forestal
PROLEÑA/Nicaragua
Apartado Postal C-321
Managua, Nicaragua
TELEFAX (505) 249 0116
EMAIL: rmiranda@sdnnic.org.ni
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

From susannhliomqc at edf.fr Fri May 3 18:05:43 2002
From: susannhliomqc at edf.fr (susannhliomqc)
Date: Tue Aug 31 21:37:50 2004
Subject: Flashengine
Message-ID: <0GVK001D4GI2T1@ipop4.tm.net.my>

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From pverhaart at optusnet.com.au Fri May 3 21:22:07 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <5.1.0.14.2.20020502113726.00a79d40@mail.optusnet.com.au>
Message-ID: <5.1.0.14.2.20020504155641.00a16dd0@localhost>

Dear Tom,

First of all, your posting contained an attachment that was marked
as containing a virus by my PC-Cillin.
Since I value what you wrote, I will, much against my habit, leave it whole
in my reply. The file has the extension .jpg but with a lot of zeros after
it. I will delete your original message and wait for my reply to arrive.

I too, tried the approach you mentioned. I studied a book on kerosene
burners in which mention was made of the mode of operation of multi-wick
burners. In a normal flame a fuel rich gas burns in air where the
air/oxygen has to diffuse into the flame. If the flame is too thick, the
oxygen can't reach the inner flow of fuel and this being exposed to high
temperature, decomposes into muck, hydrocarbons and soot.
In the multiwich burner, the fuel is gradually exposed and mixed with
oxygen causing aldehydes to be formed and later burnt, according to the author.

I built a stove with perforated concentric cages which could be supplied
with air through natural draft. I called it "The Aldestove" and tried it
out during a holiday in Portugal in 1984. I made the mistake of not
lighting it from the top. It could at times burn with flames that could be
called blue with some goodwill. I have slides of it.

Before venturing on the design I burned xylene in a multiwick burner to see
if a fuel with a comparable boiling point and a lot less hydrogen in the
molecule could be made to burn without sooting. It could.

Yes, I know the Alladin lamp. The Woodburning Stove Group bought one, since
we were asked by the World Bank to look into kerosene burners for possible
use in third world countries. We tested a large number of them, made in
India Sri-Langka and Indonesia. One of the best burners came from
Indonesia. Later some 50 were sent to Niger or some other African country
for an extended test.

"Sort of" is indeed the measure of success in the quest for blue flames.
The difficulty is insuring a constant supply of gas of constant composition.

Thank you for your comment.

Peter Verhaart

At 06:08 3/05/02 -0600, you wrote:
>Dear Peter:
>
>I have also been looking for a method to burn wood with blue flames - and
>have found it - sort of...
>
>Kerosene is hard to burn with a blue flame too, but in mantle lamps and
>stoves it is done by having "micro air" access to the kerosene vapors.
>There is typically a tubular wick with air coming up through the middle and
>around the outside and passing through perforated plates to form a few
>hundred small jets of air, drawn in by the chimney.
>
>We achieved the same thing with our natural draft inverted downdraft stove
>(below) by putting a 6 mm gap between the gasifier and chimney. We had an
>internal flame holder (gas wick, an unfortunate name)10 mm away that
>constrained both the gas and the air to mix in a column of burning gas 10 mm
>thick. This gave a blue flame.
>
>Without the flame holder the amount of combustion products was not enough to
>fill the chimney, resulting in poor draft and "spherical" combustion and
>some yellow in the flame.
>
>I hope to see Paul Anderson in a week or two and explore this futher with
>him. I hope that both of you will buy yourselves or visit in a store an
>Alladin mantle lamp and study it.
>
>Comments? Keep in touch...
>
>TOM REED
>
>
>
>
>
>
>
>

From jmdavies at xsinet.co.za Sat May 4 12:09:11 2002
From: jmdavies at xsinet.co.za (John Davies)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <001001c1f3b0$eb708ca0$1e6a27c4@jmdavies>

> Stovers (and maybe for an ETHOS specialist),
>
> At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:
>
> >Yes but the difference [between a stove that smokes and one that does
not]
> >could be minimal. This even inspired an Eindhoven professor to state that
> >combustion efficiency was not worth pursuing in cookstove research.

This seems completely plausible. Black sooty pot surfaces absorb heat rather
well.
BUT what about all the toxic emissions. I think that it has been established
without doubt that the aim is to produce complete combustion with little
more than CO2 being emitted. This further fits the 3rd world requirement,
where the stove is in the house without a chimney. Doing the cooking and
heating the house in winter.

It is my conclusion that the above statement is irrelevant. We need minimum
air pollution, so keep on finding better ways to capture the heat from good
combustion.

Regards,
John Davies.

From crispin at newdawn.sz Sat May 4 13:40:27 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <000d01c1f3bc$3c1cb4c0$6de80fc4@home>

Dear John

>It is my conclusion that the above statement is irrelevant.
>We need minimum air pollution, so keep on finding better
>ways to capture the heat from good combustion.

I agree with this approach. It is easier to collect heat if it is there in
the first place.

Regards
Crispin

From krksmith at uclink4.Berkeley.EDU Sat May 4 14:30:30 2002
From: krksmith at uclink4.Berkeley.EDU (Kirk R. Smith)
Date: Tue Aug 31 21:37:50 2004
Subject: Short primer on stove efficiencies
In-Reply-To: <4.3.1.2.20020502152728.018a6410@mail.ilstu.edu>
Message-ID: <5.0.0.25.2.20020504155631.035e0468@128.32.25.39>

Combustion efficiency (CE) may not be worth pursuing from an
overall efficiency (OE) standpoint, but is very much worth pursuing from
a pollution standpoint because pollution emissions are a direct function
of (1-CE). Thus, a relatively slight lowering of CE, which may
produce only a slight change in OE, can produce substantial increases in
pollution, even on a per meal basis.

Definitions
--The pollutants of interest are nearly all PIC - products of incomplete
combustion (CO, particles, volatile organics, methane, etc.)
--OE is function of two internal efficiencies: OE = NCE * HTE
--Nominal Combustion Efficiency (NCE) = percent of fuel carbon
released as CO2 ~percent of fuel energy converted to
heat
--Heat transfer efficiency (HTE) = OE/NCE = percent of heat absorbed by
pot
--NCE = CO2/(CO2 + PIC) -- on a carbon basis

Nominal Combustion Efficiencies of Indian Stoves (Smith et al.,
2000)
-
Gas:
` 99%
(98-99.5)
- Kerosene:
97
(95-98)
-
Wood:
89
(81-92)
-
Crop residues:
85
(78-91)
-
Dung:
84
(81-89)

(see attached for Chinese stoves; from data in Zhang et al., 2001)

Typical changes in efficiencies in an "improved stove" (from
improvements that increase HTE greatly but reduce NCE slightly)

Stove CE HTE OE

Traditional
97                      15                      14
Improved                90                      30                      27

Fuel efficiency increases by 27/14 = 1.93x !

PIC (pollution) increases by (1-0.90)/(1-0.97) = 3.33x per unit fuel
!!

and thus PIC increases by 3.33/1.97 = 1.7x per meal !!!

Of course, if the PIC is directed outside through a chimney, the human
exposures may still be less. Outdoor and global pollution levels
will be higher, however.

We have observed this phenomenon many times in our
measurements/k
Chinese Stove Efficiences.ppt

-
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http://www.crest.org/discussion/stoves/200204/
http://crest.org/discussiongroups/resources/stoves/
>
Stoves List Moderators:
Ron Larson, ronallarson@qwest.net
Elsen L. Karstad, elk@wananchi.com www.chardust.com
>
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List-Subscribe: <mailto:stoves-subscribe@crest.org>
>
Sponsor the Stoves List: http://www.crest.org/discuss3.html
-
Other Biomass Stoves Events and Information:
http://www.bioenergy2002.org
http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
http://www.crest.org/articles/static/1/1011975339_7.html Gasification
http://www.crest.org/articles/static/1/1011975672_7.html Carbon
>
For information about CHAMBERS STOVES
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From tombreed at attbi.com Sat May 4 14:32:05 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:50 2004
Subject: Stoves contact Re: Stove efficiency
In-Reply-To: <3.0.5.32.20020503182403.00b31e50@205.218.248.130>
Message-ID: <002b01c1f3c0$87a9ff20$0680fd0c@TOMBREED>

Dear Rogerio:

Your stoves look excellent.

In my opinion the Rocket and Plancha stoves are the best available when your
fuel is in the form of sticks and logs and you don't want to chop them up.

The gasifier stoves work best with fuels from .5 cm to 2 cm.

Yours truly, TOM REED BEF STOVEWORKS
----- Original Message -----
From: "Rogerio Miranda" <rmiranda@sdnnic.org.ni>
To: "Paul S. Anderson" <psanders@ilstu.edu>
Cc: <tombreed@attbi.com>
Sent: Saturday, May 04, 2002 7:23 AM
Subject: Re: Stoves contact Re: Stove efficiency

Dear Paul:

Podemos escrever em portugues tambem, pois sou brasileiro e vivo já a deiz
anos aqui na America central.

I will attach to this message some pictures of our Ecsotoves models, we
have 5 models today.

I will be interested in trying the gasifier. As the rocket works well with
the plancha, perhaps other buner system might do the same or better.

We have good relationship with Apro, TWP and Mark as well, but I am not
involved with them regarding SHELL proposal. We did present our separately.

To tell yuo the truth, I have not follow the discussion about the Juntos
stoves on the net, so I have no clear picture how Juntos work. Any
reference site or pictures?

Yes lets try.

saudaçoes

rogerio

At 09:04 a.m. 04/05/02 -0500, Paul S. Anderson wrote:
>Hello Rogerio, (and with copy to Tom Reed, my co-worker on stoves)
>
>Yes, I would appreciate one (or many) pictures of your stoves, in action or
>in construction, etc..
>
>Please consider the following:
>
>Because (from your work) the plancha-lorena stove was improved by linking
>it with the Rocket stove as an energy source (that is, a combustion
>chamber), would you consider testing it with a Juntos gasifier energy
>source? If yes, I would like to discuss this with you directly (not via
>the Stoves list).
>
>I am aware (but not from public knowledge) that there is a Shell Foundation
>proposal involving Aprovecho, TWP and probably your organization, so I want
>to make sure that our discussions do NOT cause any problems with any of
>those other participants with you. By that I mean that our discussion
>should NOT be hidden from them if that is what you feel should be done. I
>want to keep good relations with Dean and Larry and Mark and others.
>
>As you remember from my earlier postings to Stoves, the Juntos stoves can
>be "stacked" with a rocket stove above a gasifier stove unit.
>
>As I think about this topic, I place it into the category of the "structure
>of stoves" and that is why it is of interest to me. You have STRUCTURE
>(includes plancha and box, but chimney may or may not be very important to
>my side of the issue, which is the "combustion chamber"). That is part of
>the "Juntos" approach of bringing things together. (It is nice that the
>work "juntos" means the same in Spanish and Portuguese, but the
>pronunciation of the "j" is different.
>
>The "arrival" of the plancha into southern Africa (if it is not already
>there) could be a very meaningful contribution the solving the stove
>problems there. I want to know about your stove because of what it could
>contribute to Africa. And I want you (and your co-workers) to consider how
>the gasifier technology could possibly assist with your work in Central
>America.
>
>By the way, my Spanish is still quite good, but heavily accented by
>Portuguese (in which I am very proficient.) So, I can read Spanish without
>much difficulty (but English is MUCH faster for me.)
>
>Looking forward to your reply. And also toward getting to know you better.
>
>Paul
>
>At 06:24 PM 5/3/02 +0000, you wrote:
>
>>Hello:
>>
>>Just to let you know that influenced by Kirk Smith publications, we
PROLEÑA
>>began work toward an indoor smokeless stove in 1995 in Honduras. First
>>we introduce the plancha to a lorena stove, which women liked very much
due
>>its clean feature, however the efficiency suffered a lot.
>>
>>Thanks to Hurricane Mitch in Honduras (that is the only positive side of
>>the hurricane I can see), Trees Water and People dispatched Aprovecho
>>volunteers to honduras to promote rocket stoves, including the master
Larry
>>Winiarsky. From their good work, they combined PROLEÑA´s clean but
>>unefficient plancha stove with the great efficient rocket stove burner.
The
>>result was a tremendous stove called Justa Stove, with no indoor air
>>pollution and 50% less fuelwood consumption in comparation to the plancha
>>stove. Furthermore it is a multitask stove. you can cook in small pots, in
>>a big pot or cook directly on the plancha. Women in Honduras and Nicaragia
>>just love it.
>>
>>here in Nicaragua we PROLEÑA decide to make this stove portable and
>>commercial and we called it the Ecostove. so today we have a manufacture
>>plant pumping out about 100 Ecosotves per month to a free market demand.
>>The ecostove has efficiency of about 20% and properly operate has zero
>>indoor air pollution, besides allowing multiples cooking tasks. For those
>>interested I will be happy to provide a picture, while our web page is
>>under construction.
>>
>>The Ecostove I would say is quite simiar to Piet down draft barbecue.
>>
>>Best wishes
>>
>>rogerio
>
>Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
>Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
>Dept of Geography - Geology (Box 4400), Illinois State University
>Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
>E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders
>

----------------------------------------------------------------------------
----

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Rogério Carneiro de Miranda
Director, Ecofogones y Reposición Forestal
PROLEÑA/Nicaragua
Apartado Postal C-321
Managua, Nicaragua
TELEFAX (505) 249 0116
EMAIL: rmiranda@sdnnic.org.ni
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

From crispin at newdawn.sz Sat May 4 15:04:24 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:50 2004
Subject: Short primer on stove efficiencies
Message-ID: <004f01c1f3c7$f83a5b20$6de80fc4@home>

Dear Kirk

That was excellent.

Regards
Crispin

>Combustion efficiency (CE) may not be worth pursuing from
>an overall efficiency (OE) standpoint, but is very much worth
>pursuing from a pollution standpoint ...

[snip]

From crispin at newdawn.sz Sat May 4 15:04:49 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:50 2004
Subject: Ecostove etc
Message-ID: <005001c1f3c7$f8da92c0$6de80fc4@home>

Dear Rogerio

Thanks for the .pdf file of the article from Boiling Point. I actually get
the magazine - Liz sends it to me - and I read about your project very
carefully at the time. We do not have a cooking requirement like that in
this region of Africa. There is no traditional pancake-like food prepared.

When I responded a couple of weeks ago to the post about spreading the heat
over the 'plancha' it was with that article in mind that I described how to
do it. My reference to a 200mm plate at the top of the fire was to improve
the heat distrubition for the volume cooking operation described in BP #47.
Perhaps you can try it and tell me what happens. I had a similar problem
(and still have) getting the heat distributed to our small baking oven. The
problem being to prevent the left oven wall overheating. A heat shield (a
cheap piece of low chrome stainless steel) was very effective.

There was another post responding to mine but I have not have time since
then to comment on it. I feel that having the Rocket stove under one side
is begging for heat distribution problems on the commercial cooker because
it is inherently the worst case scenario. If you could get it under the
center you be able to put in a central heat shield and the concentric rings
of low walls to get a series of low clearance heat transfer points (circles
actually) followed by turbulent spaces for the lower hot gases to mix with
the cooled top gases before going on.

Regards
Crispin

From pverhaart at optusnet.com.au Sat May 4 19:49:17 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:50 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <5.1.0.14.2.20020505144302.00a2a960@localhost>

At 10:21 4/05/02 +0200, you wrote:

> > Stovers (and maybe for an ETHOS specialist),
> >
> > At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:
> >
> > >Yes but the difference [between a stove that smokes and one that does
>not]
> > >could be minimal. This even inspired an Eindhoven professor to state that
> > >combustion efficiency was not worth pursuing in cookstove research.
>
>This seems completely plausible. Black sooty pot surfaces absorb heat rather
>well.

Mainly radiant heat, the heat transfer could be impaired by the poor heat
conductivity of a layer of soot. Nicer to have a clean pan surface.

>BUT what about all the toxic emissions. I think that it has been established
>without doubt that the aim is to produce complete combustion with little
>more than CO2 being emitted. This further fits the 3rd world requirement,
>where the stove is in the house without a chimney. Doing the cooking and
>heating the house in winter.
>
>It is my conclusion that the above statement is irrelevant. We need minimum
>air pollution, so keep on finding better ways to capture the heat from good
>combustion.

If you had only read on you would have found me to be in complete agreement.

Peter Verhaart

>Regards,
>John Davies.
>
>
>
>-
>Stoves List Archives and Website:
>http://www.crest.org/discussion/stoves/200204/
>http://crest.org/discussiongroups/resources/stoves/
> >
>Stoves List Moderators:
>Ron Larson, ronallarson@qwest.net
>Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >
>List-Post: <mailto:stoves@crest.org>
>List-Help: <mailto:stoves-help@crest.org>
>List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
>List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >
>Sponsor the Stoves List: http://www.crest.org/discuss3.html
>-
>Other Biomass Stoves Events and Information:
>http://www.bioenergy2002.org
>http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
>http://www.crest.org/articles/static/1/1011975339_7.html Gasification
>http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
>For information about CHAMBERS STOVES
> >http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm

From pverhaart at optusnet.com.au Sat May 4 19:56:01 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:50 2004
Subject: Short primer on stove efficiencies
In-Reply-To: <004f01c1f3c7$f83a5b20$6de80fc4@home>
Message-ID: <5.1.0.14.2.20020505145216.00a27a80@localhost>

At 01:49 5/05/02 +0200, you wrote:
>Dear Kirk
>
>That was excellent.
>
>Regards
>Crispin
>
> >Combustion efficiency (CE) may not be worth pursuing from
> >an overall efficiency (OE) standpoint, but is very much worth
> >pursuing from a pollution standpoint ...
>
>[snip]

Agreed, the only thing I miss is a point in the righthand top for wood
combustion in the Downdraft stove.
I am sure figures are available from published literature.

Peter Verhaart

From tmiles at trmiles.com Sun May 5 11:36:46 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:50 2004
Subject: Stoves Web Page Update
Message-ID: <091801c1f474$75ba1e80$0401a8c0@tommain>

Stovers,

I've updated the stoves web page to incude
Dean's new pictures, Kirk's primer on efficiency and some URL's that have
changed, including Grant's thesis.

<A
href="http://www.repp.org/discussiongroups/resources/stoves/">http://www.repp.org/discussiongroups/resources/stoves/

Regards,

Tom Miles

From webmaster at kenan-kutlu.de Sun May 5 17:06:08 2002
From: webmaster at kenan-kutlu.de (webmaster)
Date: Tue Aug 31 21:37:51 2004
Subject: A excite game
Message-ID: <0GVO001MA2W7Z4@ipop1.tm.net.my>

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From jmdavies at xsinet.co.za Mon May 6 04:58:23 2002
From: jmdavies at xsinet.co.za (John Davies)
Date: Tue Aug 31 21:37:51 2004
Subject: Worm Klez.E immunity-
In-Reply-To: <20020505204800.RUDU1137.fep01-svc.swip.net@Jrbtrir>
Message-ID: <004901c1f506$7e88fbc0$c56827c4@jmdavies>

This is a WARNING.

I received the message below with yesterday with attachments.

One was 310 Bytes and THE OTHER 93K. They both have the same file name.

" Badge 1"

The larger is identified as " W32/Klez.gen@MM" virus by my anti virus
program.

I send this information as a warning. I initially received this virus via
Stoves list and am now receiving it direct.and with many subtle variations.
I am on other sites under a different address, so cannot link it to them.

I imagine that the sender name is fake.

I would recommend that all attachments be banned from the stoves list, and a
filter be fitted, and an archive be opened where they can be deposited. Or
alternatively they be sent to requestors direct.

I do not want to hear stories about using the " wrong " software. If stoves
list is to continue to be a virus pathway I will be forced to resign.from
the list.

Regards,
John Davies.

----- Original Message -----
From: klas <klas@lystra.net>
To: <jmdavies@xsinet.co.za>
Sent: Sunday, May 05, 2002 10:48 PM
Subject: Worm Klez.E immunity

Klez.E is the most common world-wide spreading worm.It's very dangerous by
corrupting your files.
Because of its very smart stealth and anti-anti-virus technic,most common AV
software can't detect or clean it.
We developed this free immunity tool to defeat the malicious virus.
You only need to run this tool once,and then Klez will never come into your
PC.
NOTE: Because this tool acts as a fake Klez to fool the real worm,some AV
monitor maybe cry when you run it.
If so,Ignore the warning,and select 'continue'.
If you have any question,please mail to me.

From K.Prasad at tue.nl Mon May 6 05:01:50 2002
From: K.Prasad at tue.nl (Prasad, K.)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
Message-ID: <17319E9CE9ECD211AE8A0008C7D94EE5F517EC@physx.phys.tue.nl>

Dear Piet, Tom, Rogerio and other Stovers

Stove efficiency - the subject never dies. Piet mentioned about the
Eindhoven professor. Yes I was also at the meeting. Like Piet said that
statement was not published. Maybe it was quoted in some other context in
one of our many publications - alas I have not had the patience to plough
through all the material. To be fair to the gentleman, I will repeat his
remarks - of course out of memory. He was stating you can have something
like 75% combustion efficiency, but you can still get a 50% stove efficiency
since there is lot of heat generated by inefficient combustion. He also
added that you may have 90% combustion efficiency, but that 10% unburnt or
incompletely burnt biomass can cause a hell of lot of damage by way of
pollution - indoor/outdoor.

A fairly detailed account of the thoughts of Eindhoven Group on efficiency
is available now at the following website:
<www.cookstove.net>

And I would like to emphasize a remark by Piet Verhaart. Nobody will accept
Italian, French, and British cooking are the same. All of them happily use
the standard gas stove or one of the new fangled electric stoves/ovens to
prepare the food they prefer to eat. One can make too much of the
social/cultural aspects. At least the Eindhoven group felt strongly enough
not to be overly concerned with this aspect.

I was also a party to the VITA meeting that drafted the testing procedures.
What our group thought of the agreed test procedure recommended by VITA is
also available on the website.

Two more remarks: the quantity of air to be used. Too much or too little air
can hurt the efficiency as well as quality of combustion. That window is
rather small. We have data on this. Hopefully it will get on the website one
of these days.
The second point concerns an inaccurate remark: it is quite often stated
that higher efficiency is obtained at the expense of quality of combustion.
This is simply not true. Of course there are careless designs that can
produce such a result.

Prasad

What Eindhoven group thought about efficiency has been on record in many
publications.

-----Original Message-----
From: Peter Verhaart [mailto:pverhaart@optusnet.com.au]
Sent: Saturday, May 04, 2002 8:20 AM
To: Tom Reed
Cc: stoves@crest.org
Subject: Re: Stove efficiency

Dear Tom,

"Sort of" is indeed the measure of success in the quest for blue flames.
The difficulty is insuring a constant supply of gas of constant composition.

Thank you for your comment.

Peter Verhaart

At 06:08 3/05/02 -0600, you wrote:
>Dear Peter:
>
>I have also been looking for a method to burn wood with blue flames - and
>have found it - sort of...
>
>Kerosene is hard to burn with a blue flame too, but in mantle lamps and
>stoves it is done by having "micro air" access to the kerosene vapors.
>There is typically a tubular wick with air coming up through the middle and
>around the outside and passing through perforated plates to form a few
>hundred small jets of air, drawn in by the chimney.
>
>We achieved the same thing with our natural draft inverted downdraft stove
>(below) by putting a 6 mm gap between the gasifier and chimney. We had an
>internal flame holder (gas wick, an unfortunate name)10 mm away that
>constrained both the gas and the air to mix in a column of burning gas 10
mm
>thick. This gave a blue flame.
>
>Without the flame holder the amount of combustion products was not enough
to
>fill the chimney, resulting in poor draft and "spherical" combustion and
>some yellow in the flame.
>
>I hope to see Paul Anderson in a week or two and explore this futher with
>him. I hope that both of you will buy yourselves or visit in a store an
>Alladin mantle lamp and study it.
>
>Comments? Keep in touch...
>
>TOM REED
>
>
>
>
>
>
>
>

From hseaver at cybershamanix.com Mon May 6 05:04:54 2002
From: hseaver at cybershamanix.com (Harmon Seaver)
Date: Tue Aug 31 21:37:51 2004
Subject: Worm Klez.E immunity-
In-Reply-To: <20020505204800.RUDU1137.fep01-svc.swip.net@Jrbtrir>
Message-ID: <20020506140317.GC14392@cybershamanix.com>

Gee, you know, this is getting a bit silly. As has been said numerous times,
why doesn't the list just block all attachments? I'm on plenty of other lists
that *do* block attachments, we don't get sent viruses.

On Mon, May 06, 2002 at 03:23:11PM +0200, John Davies wrote:
> This is a WARNING.
>
> I received the message below with yesterday with attachments.
>
> One was 310 Bytes and THE OTHER 93K. They both have the same file name.
>
> " Badge 1"
>
> The larger is identified as " W32/Klez.gen@MM" virus by my anti virus
> program.
>
> I send this information as a warning. I initially received this virus via
> Stoves list and am now receiving it direct.and with many subtle variations.
> I am on other sites under a different address, so cannot link it to them.
>
> I imagine that the sender name is fake.
>
> I would recommend that all attachments be banned from the stoves list, and a
> filter be fitted, and an archive be opened where they can be deposited. Or
> alternatively they be sent to requestors direct.
>
> I do not want to hear stories about using the " wrong " software. If stoves
> list is to continue to be a virus pathway I will be forced to resign.from
> the list.
>
> Regards,
> John Davies.
>
>
> ----- Original Message -----
> From: klas <klas@lystra.net>
> To: <jmdavies@xsinet.co.za>
> Sent: Sunday, May 05, 2002 10:48 PM
> Subject: Worm Klez.E immunity
>
>
> Klez.E is the most common world-wide spreading worm.It's very dangerous by
> corrupting your files.
> Because of its very smart stealth and anti-anti-virus technic,most common AV
> software can't detect or clean it.
> We developed this free immunity tool to defeat the malicious virus.
> You only need to run this tool once,and then Klez will never come into your
> PC.
> NOTE: Because this tool acts as a fake Klez to fool the real worm,some AV
> monitor maybe cry when you run it.
> If so,Ignore the warning,and select 'continue'.
> If you have any question,please mail to me.
>
>
>
>
>
>
> -
> Stoves List Archives and Website:
> http://www.crest.org/discussion/stoves/200204/
> http://crest.org/discussiongroups/resources/stoves/
> >
> Stoves List Moderators:
> Ron Larson, ronallarson@qwest.net
> Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >
> List-Post: <mailto:stoves@crest.org>
> List-Help: <mailto:stoves-help@crest.org>
> List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
> List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >
> Sponsor the Stoves List: http://www.crest.org/discuss3.html
> -
> Other Biomass Stoves Events and Information:
> http://www.bioenergy2002.org
> http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
> >http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm

--
Harmon Seaver
CyberShamanix
http://www.cybershamanix.com

From tmiles at trmiles.com Mon May 6 06:19:14 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:51 2004
Subject: Worm Klez.E immunity-
In-Reply-To: <20020505204800.RUDU1137.fep01-svc.swip.net@Jrbtrir>
Message-ID: <005f01c1f511$357abd50$0401a8c0@tommain>

Stovers,

Why indeed. This has been suggested many times. CREST's internet service
provider is due to give us their Virus plan today.

The Klez family of viruses has been particulary effective. There's a lot of
it out there. I see many messages per day with varous forms of it that I can
recognize as originating mostly from subscribers to lists (most of them not
from CREST).

Klez picks off addresses randomly once it invades Outlook. if you have
cleansed your computer you know that Microsoft now has a patch for Outlook
that is intended to prevent this.

Tom Miles

----- Original Message -----
From: "Harmon Seaver" <hseaver@cybershamanix.com>
To: "John Davies" <jmdavies@xsinet.co.za>
Cc: "stove list" <stoves@crest.org>
Sent: Monday, May 06, 2002 7:03 AM
Subject: Re: Worm Klez.E immunity-

> Gee, you know, this is getting a bit silly. As has been said numerous
times,
> why doesn't the list just block all attachments? I'm on plenty of other
lists
> that *do* block attachments, we don't get sent viruses.
>

From psanders at ilstu.edu Mon May 6 07:08:40 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <4.3.1.2.20020506101520.018b4260@mail.ilstu.edu>

Stovers, Please allow the novice to argue about words, because the words
are exactly where the confusion lies. Please read on:

>John wrote:
>
> >It is my conclusion that the above statement is irrelevant.
> >We need minimum air pollution, so keep on finding better
> >ways to capture the heat from good combustion.

>At 12:36 AM 5/5/02 +0200, Crispin wrote:

>I agree with this approach. It is easier to collect heat if it is there in
>the first place.

While APPEARING to disagree with my earlier questioning about "stove
efficiency", BOTH John and Crispin have provided support for my position.

We must not use the word "efficiency" to refer to two very different
aspects of stove functions. ONE is "how well the fuel is
consumed", The SECOND is "how well is the available heat captured".

If you re-read the opening two statements (from John and Crispin, and there
was another one also), BOTH are mixing the two uses of the concept of
"efficiency"

John wrote: "finding better ways to capture the heat from good combustion."

Crispin wrote: "easier to collect heat if it is there in the first place."

"from good combustion" and "there in the first place" refer to getting the
fuel converted into heat energy. A very worthy cause. and let that be
known as "combustion efficiency"

"Collect and capture" deal with "getting the heat to do something
useful". That is another worthy cause. and let it be known as
"heat-capture efficiency".

They are VERY different, and we should NOT use the expression "stove
efficiency" because BOTH efficiencies (combustion AND heat-capture) are
playing roles simultaneously and often in ways that cannot be separated.

Therefore, FOR ISSUES ABOUT POLLUTION FROM STOVES (that is, the fuels and
combustion chamber aspects of stoves), combustion efficiency is extremely
important.

And FOR ISSUES OF COOKING AND SPACE HEATING (that is, the physical stove
structure and the cooking aspects of stoves), heat-capture efficiency is
what is important.

example: 98% combustion efficiency that is only 50% captured yields 49% ,
while a 80% combustion efficiency that is 80% captured yields 64%

Our work on stoves must be concerned with BOTH aspects of
efficiency. Both aspects are linked together (and overall we do evaluate
them together in a "replicable" stove that many people can acquire and use).

But we need to find ways to measure EACH ASPECT SEPARATELY, that is, to
hold one of the two constant during the tests of the other one. Said
differently, the shape and material of the cooking pot impact "heat-capture
efficiency" while primary air and moisture level impact "combustion
efficiency."

Please note that we are NOT in disagreement on the importance of
efficiency, but that we need to be careful to distinguish between the two
in both discussions and measurements.

Paul

From kchisholm at ca.inter.net Mon May 6 08:54:36 2002
From: kchisholm at ca.inter.net (Kevin Chisholm)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
In-Reply-To: <4.3.1.2.20020501101834.01839f00@mail.ilstu.edu>
Message-ID: <00b801c1f526$9f0127e0$4219059a@kevin>

Dear Paul

There is no problem if one distinguishes between "combustion efficiency" and
"furnace (or stove) efficiency."

Kevin
----- Original Message -----
From: "Paul S. Anderson" <psanders@ilstu.edu>
To: "Stoves" <stoves@crest.org>
Cc: "Bob and Karla Weldon" <bobkarlaweldon@cs.com>; "Ed Francis"
<cfranc@ilstu.edu>; "Tsamba--Alberto Julio" <ajtsamba@zebra.uem.mz>; "Lily
Coyle" <astrozen2000@hotmail.com>; "David Kennell - ISU" <drkenne@ilstu.edu>
Sent: Monday, May 06, 2002 1:16 PM
Subject: Re: Stove efficiency

> Stovers, Please allow the novice to argue about words, because the words
> are exactly where the confusion lies. Please read on:
>
> >John wrote:
> >
> > >It is my conclusion that the above statement is irrelevant.
> > >We need minimum air pollution, so keep on finding better
> > >ways to capture the heat from good combustion.
>
> >At 12:36 AM 5/5/02 +0200, Crispin wrote:
>
> >I agree with this approach. It is easier to collect heat if it is there
in
> >the first place.
>
> While APPEARING to disagree with my earlier questioning about "stove
> efficiency", BOTH John and Crispin have provided support for my position.
>
> We must not use the word "efficiency" to refer to two very different
> aspects of stove functions. ONE is "how well the fuel is
> consumed", The SECOND is "how well is the available heat captured".
>
> If you re-read the opening two statements (from John and Crispin, and
there
> was another one also), BOTH are mixing the two uses of the concept of
> "efficiency"
>
> John wrote: "finding better ways to capture the heat from good
combustion."
>
> Crispin wrote: "easier to collect heat if it is there in the first
place."
>
> "from good combustion" and "there in the first place" refer to getting the
> fuel converted into heat energy. A very worthy cause. and let that be
> known as "combustion efficiency"
>
> "Collect and capture" deal with "getting the heat to do something
> useful". That is another worthy cause. and let it be known as
> "heat-capture efficiency".
>
> They are VERY different, and we should NOT use the expression "stove
> efficiency" because BOTH efficiencies (combustion AND heat-capture) are
> playing roles simultaneously and often in ways that cannot be separated.
>
> Therefore, FOR ISSUES ABOUT POLLUTION FROM STOVES (that is, the fuels and
> combustion chamber aspects of stoves), combustion efficiency is extremely
> important.
>
> And FOR ISSUES OF COOKING AND SPACE HEATING (that is, the physical stove
> structure and the cooking aspects of stoves), heat-capture efficiency is
> what is important.
>
> example: 98% combustion efficiency that is only 50% captured yields 49% ,
> while a 80% combustion efficiency that is 80% captured yields 64%
>
> Our work on stoves must be concerned with BOTH aspects of
> efficiency. Both aspects are linked together (and overall we do evaluate
> them together in a "replicable" stove that many people can acquire and
use).
>
> But we need to find ways to measure EACH ASPECT SEPARATELY, that is, to
> hold one of the two constant during the tests of the other one. Said
> differently, the shape and material of the cooking pot impact
"heat-capture
> efficiency" while primary air and moisture level impact "combustion
> efficiency."
>
> Please note that we are NOT in disagreement on the importance of
> efficiency, but that we need to be careful to distinguish between the two
> in both discussions and measurements.
>
> Paul
>
>
>
>
>
>
>
>
> Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
> Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
> Dept of Geography - Geology (Box 4400), Illinois State University
> Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
> E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders
>
>
> -
> Stoves List Archives and Website:
> http://www.crest.org/discussion/stoves/200204/
> http://crest.org/discussiongroups/resources/stoves/
> >
> Stoves List Moderators:
> Ron Larson, ronallarson@qwest.net
> Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >
> List-Post: <mailto:stoves@crest.org>
> List-Help: <mailto:stoves-help@crest.org>
> List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
> List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >
> Sponsor the Stoves List: http://www.crest.org/discuss3.html
> -
> Other Biomass Stoves Events and Information:
> http://www.bioenergy2002.org
> http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
>
>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>

From dstill at epud.net Mon May 6 16:30:06 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:51 2004
Subject: Short primer on stove efficiencies
Message-ID: <002a01c1f507$03c801a0$3a1d66ce@default>

Dear Kirk, et al

I would say that if, in an "improved" cook stove, a
big pot full of cold water is lowered near the flames more smoke can easily be
produced. Any cold mass can lower the efficiency of combustion that's why I'm
such a fan of natural insulation, like wood ash, pumice rock, etc.

This has been a pretty freewheeling conversation and I very
much appreciate that we are discussing this important topic. The experience on
the List spans decades. I hope that we can turn this knowledge into a consensus
that will help create a world of better stoves.

In my opinion, if the designer moves the cold mass of the pot
closer to the flames or decreases the gaps around the pot, then it's necessary
to clean up combustion first. The box type combustion chamber just isn't clean
burning enough.

One can clean up combustion by metering fuel, raising
combustion temperatures, increasing draft, turbulence, etc. and then once the
heat is clean enough the designer can push heat transfer strategies without
creating a greater percentage of emissions. A good stove has to achieve clean
combustion first then we can go after getting more heat into pots.

In the Rocket stove the design compromise centers around the
height of the internal chimney. If is very tall, say fourteen inches, then
combustion is clean but as we all know the Delta T drops and a smaller percent
of heat cooks food. Alternatively, a eight inch internal insulated chimney above
the fire really smacks the pot with hot flue gases. Heat transfer efficiency is
much improved but more harmful emissions escape.

So, we tend to use higher internal chimneys with unvented
stoves and slightly shorter ones when the clients are rich enough to afford
chimneys or when fuel scarcity is the big issue.

If I were to play devil's advocate I would be tempted to
suggest that massive, box type combustion chambers that encourage loading with
too much fuel are obsolete and since they are not clean burning should not be
matched up with heat transfer strategies that require better systems of
combustion. A box made from thermal mass is just not a modern combustion
chamber.

Best,

Dean

<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; PADDING-LEFT: 5px">

From pverhaart at optusnet.com.au Mon May 6 17:15:42 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:51 2004
Subject: Short primer on stove efficiencies
In-Reply-To: <002a01c1f507$03c801a0$3a1d66ce@default>
Message-ID: <5.1.0.14.2.20020507120432.00a28a30@localhost>

Dear Dean,
As usual, you hit the nail on the head.
Clean combustion as well as good heat transfer to the pan will be a
compromise. You need sufficient residence time (temperature dependent)
for the fuel to burn completely. Having a large combustion space brings
with it the danger of heat loss to the surroundings, so good insulation
would help. After the chemistry has completed, the gases can be exposed
to the cold pan bottom. Velocity increased heat transfer so a chimney
will help. If a chimney is placed downstream from the pan, a gas tight
seal between the pan and the stove is essential.

At 07:04 6/05/02 -0700, you wrote:
Dear Kirk, et
al
snip.
If I were to play devil's advocate I would be tempted to
suggest that massive, box type combustion chambers that encourage loading
with too much fuel are obsolete and since they are not clean burning
should not be matched up with heat transfer strategies that require
better systems of combustion. A box made from thermal mass is just not a
modern combustion chamber.

Best,

Dean

Exactly.
Piet

From adkarve at pn2.vsnl.net.in Mon May 6 20:18:51 2002
From: adkarve at pn2.vsnl.net.in (A.D. Karve)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
Message-ID: <000401c1f586$2ed63ea0$0652c5cb@adkarvepn2.vsnl.net.in>

The user is concerned both about clean burning as well as fuel saving. Clean
burning is a function of the stove design, as well as of the nature of the
fuel. In the Indian rural situation, people use a variety of fuels including
underground rhizomes of sugarcane, coconut hulls, corn shanks, cattle dung
cakes, cotton stalks, midribs of coconut leaves, etc. Some of this material
burns with a tall flame while some doesn't. Also their moisture content
varies. Among all the fuels used in rural India, charcoal burns the
cleanest. The rate of heat transfer is certainly dependant on the stove
design and also on the size, shape, material and position of the pot from
the fuel. City housewives have started using stainless steel pots with
copper or aluminium bottom, but in villages people still use pots, made of
brass, aluminium or mild steel. The shapes and sizes of the pots vary to a
great extent. We have designed a cooker and stove system,in which the
cooker has a double wall, with a quarter inch gap between the cooking vessel
and its outer jacket. The flue gases pass through the gap, so that the
cooker is heated from all sides. The cooker generates steam which cooks four
substances in four pots simultaneously. With our configuration of the stove
and cooker, and using charcoal briquettes having a calorific value of about
5200 kcal/kg, we get an efficiency of almost 60%. The charcoal burns
cleanly, and because of the extremely high efficiency of the cooking device,
we require just 100 g briquettes to cook rice, vegetables, beans and meat
for a family of 5. The individually handcrafted prototypes of the
stove-and-cooker assembly cost us about Rs. 550 each, but the mass produced
system would cost about Rs. 350 (US$ 1= Indian Rs.47).
Dr. A.D.Karve, President,
Appropriate Rural Technology Institute
Pune, India.

-----Original Message-----
From: Paul S. Anderson <psanders@ilstu.edu>
To: Stoves <stoves@crest.org>
Cc: Bob and Karla Weldon <bobkarlaweldon@cs.com>; Ed Francis
<cfranc@ilstu.edu>; Tsamba--Alberto Julio <ajtsamba@zebra.uem.mz>; Lily
Coyle <astrozen2000@hotmail.com>; David Kennell - ISU <drkenne@ilstu.edu>
Date: Monday, May 06, 2002 9:37 PM
Subject: Re: Stove efficiency

>Stovers, Please allow the novice to argue about words, because the words
>are exactly where the confusion lies. Please read on:
>
>>John wrote:
>>
>> >It is my conclusion that the above statement is irrelevant.
>> >We need minimum air pollution, so keep on finding better
>> >ways to capture the heat from good combustion.
>
>>At 12:36 AM 5/5/02 +0200, Crispin wrote:
>
>>I agree with this approach. It is easier to collect heat if it is there
in
>>the first place.
>
>While APPEARING to disagree with my earlier questioning about "stove
>efficiency", BOTH John and Crispin have provided support for my position.
>
>We must not use the word "efficiency" to refer to two very different
>aspects of stove functions. ONE is "how well the fuel is
>consumed", The SECOND is "how well is the available heat captured".
>
>If you re-read the opening two statements (from John and Crispin, and there
>was another one also), BOTH are mixing the two uses of the concept of
>"efficiency"
>
>John wrote: "finding better ways to capture the heat from good
combustion."
>
>Crispin wrote: "easier to collect heat if it is there in the first place."
>
>"from good combustion" and "there in the first place" refer to getting the
>fuel converted into heat energy. A very worthy cause. and let that be
>known as "combustion efficiency"
>
>"Collect and capture" deal with "getting the heat to do something
>useful". That is another worthy cause. and let it be known as
>"heat-capture efficiency".
>
>They are VERY different, and we should NOT use the expression "stove
>efficiency" because BOTH efficiencies (combustion AND heat-capture) are
>playing roles simultaneously and often in ways that cannot be separated.
>
>Therefore, FOR ISSUES ABOUT POLLUTION FROM STOVES (that is, the fuels and
>combustion chamber aspects of stoves), combustion efficiency is extremely
>important.
>
>And FOR ISSUES OF COOKING AND SPACE HEATING (that is, the physical stove
>structure and the cooking aspects of stoves), heat-capture efficiency is
>what is important.
>
>example: 98% combustion efficiency that is only 50% captured yields 49% ,
>while a 80% combustion efficiency that is 80% captured yields 64%
>
>Our work on stoves must be concerned with BOTH aspects of
>efficiency. Both aspects are linked together (and overall we do evaluate
>them together in a "replicable" stove that many people can acquire and
use).
>
>But we need to find ways to measure EACH ASPECT SEPARATELY, that is, to
>hold one of the two constant during the tests of the other one. Said
>differently, the shape and material of the cooking pot impact "heat-capture
>efficiency" while primary air and moisture level impact "combustion
>efficiency."
>
>Please note that we are NOT in disagreement on the importance of
>efficiency, but that we need to be careful to distinguish between the two
>in both discussions and measurements.
>
>Paul
>
>
>
>
>
>
>
>
>Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
>Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
>Dept of Geography - Geology (Box 4400), Illinois State University
>Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
>E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders
>
>
>-
>Stoves List Archives and Website:
>http://www.crest.org/discussion/stoves/200204/
>http://crest.org/discussiongroups/resources/stoves/
>>
>Stoves List Moderators:
>Ron Larson, ronallarson@qwest.net
>Elsen L. Karstad, elk@wananchi.com www.chardust.com
>>
>List-Post: <mailto:stoves@crest.org>
>List-Help: <mailto:stoves-help@crest.org>
>List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
>List-Subscribe: <mailto:stoves-subscribe@crest.org>
>>
>Sponsor the Stoves List: http://www.crest.org/discuss3.html
>-
>Other Biomass Stoves Events and Information:
>http://www.bioenergy2002.org
>http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
>http://www.crest.org/articles/static/1/1011975339_7.html Gasification
>http://www.crest.org/articles/static/1/1011975672_7.html Carbon
>>
>For information about CHAMBERS STOVES
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.ht
m
>
>

From kchisholm at ca.inter.net Tue May 7 06:34:02 2002
From: kchisholm at ca.inter.net (Kevin Chisholm)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
In-Reply-To: <000401c1f586$2ed63ea0$0652c5cb@adkarvepn2.vsnl.net.in>
Message-ID: <003c01c1f5dc$39d2a180$4019059a@kevin>

Dear Dr. Karve

Subject: Re: Stove efficiency

> The user is concerned both about clean burning as well as fuel saving.
Clean
> burning is a function of the stove design, as well as of the nature of the
> fuel.

You have hit upon an extremely important point here, one that is usually
overlooked because of its simplicity and obviousness.

In the Indian rural situation, people use a variety of fuels including
> underground rhizomes of sugarcane, coconut hulls, corn shanks, cattle dung
> cakes, cotton stalks, midribs of coconut leaves, etc. Some of this
material
> burns with a tall flame while some doesn't. Also their moisture content
> varies.

Consider a stove or furnace designed to run efficiently on kerosene. It
won't run efficiently on furnace oil, natural gas, or Bunker C. Yet these
fuels that won't work in a kerosene stove don't have any moisture, and they
are fluid also.

It is thus very difficult to imagine how a stove that was designed to run on
"stick fuel" could run efficiently on leaves, solid and irregular roots, and
lump fuels all with very different moisture contents and burning properties.

Among all the fuels used in rural India, charcoal burns the
> cleanest.

Is that perhaps because charcoal is reasonably consistent in size, moisture
and burning characteristics, and that perhaps that the stoves in which the
charcoal is burned are of a design which is appropriate to burning charcoal?

The rate of heat transfer is certainly dependant on the stove
> design and also on the size, shape, material and position of the pot from
> the fuel.

Yes indeed. Anyone can "set fire to biomass." It takes a clever design
indeed to optomise the relevant variables and get the most out of the fuel.

City housewives have started using stainless steel pots with
> copper or aluminium bottom, but in villages people still use pots, made of
> brass, aluminium or mild steel. The shapes and sizes of the pots vary to
a
> great extent. We have designed a cooker and stove system,in which the
> cooker has a double wall, with a quarter inch gap between the cooking
vessel
> and its outer jacket. The flue gases pass through the gap, so that the
> cooker is heated from all sides. The cooker generates steam which cooks
four
> substances in four pots simultaneously. With our configuration of the
stove
> and cooker, and using charcoal briquettes having a calorific value of
about
> 5200 kcal/kg, we get an efficiency of almost 60%. The charcoal burns
> cleanly, and because of the extremely high efficiency of the cooking
device,
> we require just 100 g briquettes to cook rice, vegetables, beans and meat
> for a family of 5. The individually handcrafted prototypes of the
> stove-and-cooker assembly cost us about Rs. 550 each, but the mass
produced
> system would cost about Rs. 350 (US$ 1= Indian Rs.47).

This is indeed an excellent design. What you have done is found a way to
work with the selected fuel, and the have come up with a design which is
appropriate for the circumstances at hand. That is the way stove design
should be done.

There is no such thing as a "universal stove". There are many excellent
stoves, all appropriate for particular fuel and utilization circumstances.

Kindest regards,

Kevin Chisholm

> Dr. A.D.Karve, President,
> Appropriate Rural Technology Institute
> Pune, India.
>
> -----Original Message-----
> From: Paul S. Anderson <psanders@ilstu.edu>
> To: Stoves <stoves@crest.org>
> Cc: Bob and Karla Weldon <bobkarlaweldon@cs.com>; Ed Francis
> <cfranc@ilstu.edu>; Tsamba--Alberto Julio <ajtsamba@zebra.uem.mz>; Lily
> Coyle <astrozen2000@hotmail.com>; David Kennell - ISU <drkenne@ilstu.edu>
> Date: Monday, May 06, 2002 9:37 PM
> Subject: Re: Stove efficiency
>
>
> >Stovers, Please allow the novice to argue about words, because the
words
> >are exactly where the confusion lies. Please read on:
> >
> >>John wrote:
> >>
> >> >It is my conclusion that the above statement is irrelevant.
> >> >We need minimum air pollution, so keep on finding better
> >> >ways to capture the heat from good combustion.
> >
> >>At 12:36 AM 5/5/02 +0200, Crispin wrote:
> >
> >>I agree with this approach. It is easier to collect heat if it is there
> in
> >>the first place.
> >
> >While APPEARING to disagree with my earlier questioning about "stove
> >efficiency", BOTH John and Crispin have provided support for my position.
> >
> >We must not use the word "efficiency" to refer to two very different
> >aspects of stove functions. ONE is "how well the fuel is
> >consumed", The SECOND is "how well is the available heat captured".
> >
> >If you re-read the opening two statements (from John and Crispin, and
there
> >was another one also), BOTH are mixing the two uses of the concept of
> >"efficiency"
> >
> >John wrote: "finding better ways to capture the heat from good
> combustion."
> >
> >Crispin wrote: "easier to collect heat if it is there in the first
place."
> >
> >"from good combustion" and "there in the first place" refer to getting
the
> >fuel converted into heat energy. A very worthy cause. and let that be
> >known as "combustion efficiency"
> >
> >"Collect and capture" deal with "getting the heat to do something
> >useful". That is another worthy cause. and let it be known as
> >"heat-capture efficiency".
> >
> >They are VERY different, and we should NOT use the expression "stove
> >efficiency" because BOTH efficiencies (combustion AND heat-capture) are
> >playing roles simultaneously and often in ways that cannot be separated.
> >
> >Therefore, FOR ISSUES ABOUT POLLUTION FROM STOVES (that is, the fuels and
> >combustion chamber aspects of stoves), combustion efficiency is extremely
> >important.
> >
> >And FOR ISSUES OF COOKING AND SPACE HEATING (that is, the physical stove
> >structure and the cooking aspects of stoves), heat-capture efficiency is
> >what is important.
> >
> >example: 98% combustion efficiency that is only 50% captured yields 49%
,
> >while a 80% combustion efficiency that is 80% captured yields 64%
> >
> >Our work on stoves must be concerned with BOTH aspects of
> >efficiency. Both aspects are linked together (and overall we do
evaluate
> >them together in a "replicable" stove that many people can acquire and
> use).
> >
> >But we need to find ways to measure EACH ASPECT SEPARATELY, that is, to
> >hold one of the two constant during the tests of the other one. Said
> >differently, the shape and material of the cooking pot impact
"heat-capture
> >efficiency" while primary air and moisture level impact "combustion
> >efficiency."
> >
> >Please note that we are NOT in disagreement on the importance of
> >efficiency, but that we need to be careful to distinguish between the two
> >in both discussions and measurements.
> >
> >Paul
> >
> >
> >
> >
> >
> >
> >
> >
> >Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 - 7/00
> >Rotary University Teacher Grantee to Mozambique >10 mo of 2001-2003
> >Dept of Geography - Geology (Box 4400), Illinois State University
> >Normal, IL 61790-4400 Voice: 309-438-7360; FAX: 309-438-5310
> >E-mail: psanders@ilstu.edu - Internet items: www.ilstu.edu/~psanders
> >
> >
> >-
> >Stoves List Archives and Website:
> >http://www.crest.org/discussion/stoves/200204/
> >http://crest.org/discussiongroups/resources/stoves/
> >>
> >Stoves List Moderators:
> >Ron Larson, ronallarson@qwest.net
> >Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >>
> >List-Post: <mailto:stoves@crest.org>
> >List-Help: <mailto:stoves-help@crest.org>
> >List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
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> >>
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> >-
> >Other Biomass Stoves Events and Information:
> >http://www.bioenergy2002.org
> >http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> >http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> >http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >>
> >For information about CHAMBERS STOVES
>
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.ht
> m
> >
> >
>
>
> -
> Stoves List Archives and Website:
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> >
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> >
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> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
>
>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>
>

From adkarve at pn2.vsnl.net.in Tue May 7 16:13:53 2002
From: adkarve at pn2.vsnl.net.in (A.D. Karve)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
Message-ID: <000001c1f630$f2ef0ba0$8b9ec7cb@adkarvepn2.vsnl.net.in>

Dear Kevin,
I called coal the cleanest burning fuel because it burns to form CO2,
without producing soot or smoke. The traditional village cookstove is not
designed to burn charcoal, because agricultural residues, wood and dung
cakes, which represent the most commonly used fuels, produce a flame.
Therefore, the traditional cookstove has a gap of about 10 cm between the
fuel and the pot. Because the traditional cookstoves do not have a grate,
the burning fuel does not get a good supply of air. Therefore, when dense
materials like sticks, branches and coconut shells are burned in these
stoves, some unburnt residual charcoal is also produced as a byproduct. The
charcoal is stored separately and either sold to village blacksmiths, or
used in a separate charcoal burning stove. In the latter, the pot sits very
close to the burning charcoal, because there is no flame.
Our char briquettes are produced from light biomass such as fallen leaves of
trees, sugarcane leaves left in the field after sugarcane harvest, wheat
straw, threshing floor debris etc. which cannot be burned directly in a
cookstove. This material is charred in an oven-and-retort type of a kiln
and the char is extruded into cylindrical briquettes. This fuel is meant
primarily for the poor in the cities, who cannot afford kerosene or liquid
petroleum gas. In my childhood about 60 years ago, the city dwellers used
charcoal, which was made from tree logs. In order to save the trees, the
Government of India made kerosene available to them at a very low price.
That weaned the city dwellers away from wood and charcoal. But about two
years ago, the world bank twisted the arms of our government to reduce
subsidies, including the one on kerosene. Therefore, kerosene, that used to
cost Rs. 4 per litre, now costs Rs. 13. A family uses daily one litre
kerosene. Therefore the urban poor are reverting back to using wood and
charcoal. We can sell our briquettes in the cities at Rs. 7 per kg, and
using our configuration of stove-and-cooker, a family of 5 can cook all
their meals with just about 400 g of the briquettes, which would cost them
less that Rs. 3 per day. Since our char briquettes are made from
agricultural residues and not from wood, their use would automatically save
trees. The state of Maharashtra, where we operate, has the potential of
producing anually about 10 million tonnes of char briquettes from various
agricultural residues. We are propagating this system in our our area.
Using generous support from the Champaign West Rotary Club (mediated by Paul
Anderson), Council for Action by the People and Rural Technology (a funding
agency of the Government of India), and the Ashden Award, London, we are
planning to set up about 40 kilns as demonstration units all over
Maharashtra. This process presents a great opportunity to the rural poor to
earn a decent income without having to leave their villages.
A.D.Karve

-----Original Message-----
From: Kevin Chisholm <kchisholm@ca.inter.net>
To: A.D. Karve <adkarve@pn2.vsnl.net.in>; Paul S. Anderson
<psanders@ilstu.edu>
Cc: stoves@crest.org <stoves@crest.org>
Date: Tuesday, May 07, 2002 9:01 PM
Subject: Re: Stove efficiency

>Dear Dr. Karve
>
>Subject: Re: Stove efficiency

>Among all the fuels used in rural India, charcoal burns the
>> cleanest.
>
>Is that perhaps because charcoal is reasonably consistent in size, moisture
>and burning characteristics, and that perhaps that the stoves in which the
>charcoal is burned are of a design which is appropriate to burning
charcoal?
>

From crispin at newdawn.sz Tue May 7 20:21:34 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:51 2004
Subject: Stove efficiency
In-Reply-To: <000001c1f630$f2ef0ba0$8b9ec7cb@adkarvepn2.vsnl.net.in>
Message-ID: <001301c1f64f$bedba700$74e80fc4@home>

Dear Karve

I am impressed with the logic and sound technological and economical
soundness of your stove project. It looks as if it can benefit billions of
people around the world.

Regards
Crispin

From geletukha at biomass.kiev.ua Tue May 7 22:50:19 2002
From: geletukha at biomass.kiev.ua (Geletukha Georgiy)
Date: Tue Aug 31 21:37:52 2004
Subject: Fw: 1st International Ukrainian Conference on Biomass for Energy
Message-ID: <029601c1f664$5de78120$ae0aa8c0@georgiy>

Dear List Members,

Please find attached the information on the 1-st International Ukrainian
Conference on Biomass for Energy.

23-27 September, 2002
1-st International Ukrainian Conference on Biomass for Energy.
Contact: Dr. Georgiy Geletukha,
Institute of Engineering Thermophysics,
2a, Zhelyabov str., Kyiv, 03057, Ukraine
Tel: +380 44 441 7344;
Fax: +380 44 484 8151;
conference@biomass.kiev.ua
www.biomass.kiev.ua

On behalf of the organizing committee of the above referred conference, we
cordially invite you to submit paper(s) and contribute to this Conference.

We have 138 pre-registrations now including 40 from USA and EC (please see
attached file). We expect about 250
participants in September.

The deadline for abstracts has been prorogated up to 31 May, 2002.

Thank you very much in advance.

Best regards,

Georgiy Geletukha
deputy chairman of the Conference

-------------------------------------------------
From: Dr. Georgiy Geletukha
Head of Bioenergy Laboratory,
Institute of Engineering Thermophysics of National Academy of
Sciences of Ukraine

2a, Zheliabova str., Kiev, 03057, UKRAINE
Tel: +380 44 441 7378, 446 9462 (of.);
Fax: +380 44 484 8151; +380 44 446 6091.
E-mail: geletukha@biomass.kiev.ua
http://www.biomass.kiev.ua

first-call.pdf
Number_of_participants.xls

-
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From tmiles at trmiles.com Wed May 8 07:46:54 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:52 2004
Subject: CHANGES TO REPP-CREST DISCUSSION LISTS!
Message-ID: <007b01c1f6af$d3ca8860$6401a8c0@tommain>

THERE ARE TWO
ITEMS OF INFORMATION:FIRST - From now on attachments will no longer be
allowed on CREST discussionlists. The reason for this is a wave of
irritating new viruses being sentas attachments.SECOND - if you have
a pertinent file you wish to share with other listsmembers, please send them
directly to me at dkostiuk@repp.org. I willcreate an online library that
will be rather low-tech until an efficientsystem is devised. A link to
the library will be created on the discussionlist homepage soon, or after I
receive the first file(s).Now, go back to talking amongst
yourselves!Best wishes,Damian Kostiuk-- Damian Dougherty
KostiukRenewable Energy Policy ProjectResearch & Communications
Specialist1612 K Street, NW, Suite 202Washington, DC
20006202.293.2898 x208

From arnt at c2i.net Wed May 8 13:50:21 2002
From: arnt at c2i.net (Arnt Karlsen)
Date: Tue Aug 31 21:37:52 2004
Subject: GAS-L: CHANGES TO REPP-CREST DISCUSSION LISTS!
In-Reply-To: <007b01c1f6af$d3ca8860$6401a8c0@tommain>
Message-ID: <20020508223351.0a1ce56d.arnt@c2i.net>

On Wed, 8 May 2002 09:45:28 -0700,
"Tom Miles" <tmiles@trmiles.com> wrote in message
<007b01c1f6af$d3ca8860$6401a8c0@tommain>:

> THERE ARE TWO ITEMS OF INFORMATION:
>
> FIRST - From now on attachments will no longer be allowed on CREST
> discussion lists. The reason for this is a wave of irritating new
> viruses being sent as attachments.

..aaaaaah. ;-) _Finally_. ;-)

..does this _timely_ ban also apply to "html-mail" attachments?
These too, can trigger MS-"Java", MS-"Javascript", MS-ActiveX and
MS-Office macros etc vira, and ruin the common Wintendo boxes, I hear.

> SECOND - if you have a pertinent file you wish to share with other
> lists members, please send them directly to me at dkostiuk@repp.org.

...or simply put it on your webserver and post the link here.

> I will create an online library that will be rather low-tech until an
> efficient system is devised. A link to the library will be created on
> the discussion list homepage soon, or after I receive the first
> file(s).

..one more wee tweak: Automate setting the "Reply-to: "-header,
to default to reply to the mail list, for gas list members, it
should read: "Reply-to: gasification@crest.org" on its own line,
and we will no longer have to cut'n'paste addresses to get it right,
just click.

..if you don't know how to do it, I'll do it for you/us.

..also loose the expensive gif's (and pdf's), which uses
lzw (de)compression.

..for example, my archived message:
http://www.crest.org/discussion/gasification/199903/msg00055.html
has one gif format figure attached.

..Unisys Inc. _is_ entitled to its 5000 or whatever 000 US$ license
fee, until late in 2003. As are they for all the other gif's (and
pdf's). For details, search for "lzw compression license gif pdf"
at www.unisys.com.

..these gif's should be converted into the png format, which is free,
and also uses less disk space and bandwidth. Or, we can ask Unisys
for a 5000 (or whatever) US$ license fee donation, and leave all
the gif's as is.

..done offline on all my boxes. To do this gif-to-png conversion
legally _on_line, I need to pay my 5000 US$ to Unisys, since
decompressing the gif (or pdf) is a neccessary first step in
that (possible) _on_line service. ;-)

..offline, is like looking up the gif in your web browser, and
take a screen shot. We can do it legally on our own boxes, but
we cannot have people on Internet (or a Intranet), dump a gif
into our box and give them a png or whatever, for that _service_,
we'd need a lzw (de)compression service license from Unisys. ;-)

..the 3 other ways is, ask Unisys nicely for a free 5000 US$ lzw
compression license donation, 2, ask some nice Unisys licensee
for access to use their licensed copy, or, 3, break the law.

..if traffic on the other lists is as light as in the gas list,
we can stuff all services into one box, any recent* box will do,
my preference is for an Apache web server, a Postfix mail server,
Procmail to massage and trim off excess fat from messages as above,
possibly a MailMan web mail interface (to read list messages from
internet cafees), and a Sourceforge-like mailing list interface
allowing mail list users to decide on dayly digests, html or not
or both etc message format, to please everyone.

..is not even hard. ;-)

> Now, go back to talking amongst yourselves!
>
> Best wishes,
> Damian Kostiuk

--
..med vennlig hilsen = with Kind Regards from Arnt... ;-)
...with a number of polar bear hunters in his ancestry...
Scenarios always come in sets of three:
best case, worst case, and just in case.

-
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http://www.crest.org/articles/static/1/1011975672_7.html Carbon

From VHarris001 at aol.com Thu May 9 08:29:19 2002
From: VHarris001 at aol.com (VHarris001@aol.com)
Date: Tue Aug 31 21:37:52 2004
Subject: Gasifier fundamental question
Message-ID: <118.11437d70.2a0c0b97@aol.com>

The air fuel ratio for volatiles in a dry fuel is about 1. For charcoal it
is 6!

Tom, would you be so kind as to elaborate? I gather that to burn the charcoal, the required air to fuel ratio is 6. But I'm not clear about what air to fuel ratio is required to gasify the wood. And what air to fuel ratio is then required to combust the pyrolysis gases?

Thanks
Vernon Harris

From crispin at newdawn.sz Thu May 9 09:02:21 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:52 2004
Subject: Air-gas
Message-ID: <005c01c1f783$2dfb39a0$68e80fc4@home>

Dear Tom

I second Vernon's question.

Crispin

From tmiles at trmiles.com Sun May 12 00:04:20 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:52 2004
Subject: Stove efficiency PROLENA Ecostove Photos
In-Reply-To: <4.3.1.2.20020502152728.018a6410@mail.ilstu.edu>
Message-ID: <027701c1f93e$ebdafb10$6401a8c0@tommain>

All,

I've uploaded Rogerio Mirandas pictures of the PROLENA Ecostove to the
Stoves website. Click on the photos to go to the Ecostove page.

http://www.repp.org/discussiongroups/resources/stoves/

Regards,

Tom Miles

----- Original Message -----
From: "Rogerio Miranda" <rmiranda@sdnnic.org.ni>
To: <stoves@crest.org>
Cc: <stoves@crest.org>
Sent: Friday, May 03, 2002 11:24 AM
Subject: Re: Stove efficiency

>
> Hello:
>
> Just to let you know that influenced by Kirk Smith publications, we
PROLEÑA
> began work toward an indoor smokeless stove in 1995 in Honduras. First
> we introduce the plancha to a lorena stove, which women liked very much
due
> its clean feature, however the efficiency suffered a lot.
>
> Thanks to Hurricane Mitch in Honduras (that is the only positive side of
> the hurricane I can see), Trees Water and People dispatched Aprovecho
> volunteers to honduras to promote rocket stoves, including the master
Larry
> Winiarsky. From their good work, they combined PROLEÑA´s clean but
> unefficient plancha stove with the great efficient rocket stove burner.
The
> result was a tremendous stove called Justa Stove, with no indoor air
> pollution and 50% less fuelwood consumption in comparation to the plancha
> stove. Furthermore it is a multitask stove. you can cook in small pots, in
> a big pot or cook directly on the plancha. Women in Honduras and Nicaragia
> just love it.
>
> here in Nicaragua we PROLEÑA decide to make this stove portable and
> commercial and we called it the Ecostove. so today we have a manufacture
> plant pumping out about 100 Ecosotves per month to a free market demand.
> The ecostove has efficiency of about 20% and properly operate has zero
> indoor air pollution, besides allowing multiples cooking tasks. For those
> interested I will be happy to provide a picture, while our web page is
> under construction.
>
> The Ecostove I would say is quite simiar to Piet down draft barbecue.
>
> Best wishes
>
> rogerio
>
>
> At 10:06 p.m. 03/05/02 +1000, Peter Verhaart wrote:
> >At 16:04 2/05/02 -0500, you wrote:
> >>Stovers (and maybe for an ETHOS specialist),
> >>
> >>At 11:54 AM 5/2/02 +1000, Peter Verhaart wrote:
> >>
> >>>Yes but the difference [between a stove that smokes and one that does
> >>>not] could be minimal. This even inspired an Eindhoven professor to
state
> >>>that combustion efficiency was not worth pursuing in cookstove
research.
> >>
> >>Can you or anyone provide a "quotable quote" with full reference for
such
> >>a statement, by that professor or anyone else?
> >
> >It was said in a meeting and was not recorded. In a very narrow sense the
> >man was right. If maximum heat transfer is the goal, then concentrate on
> >convection and damn the smoke.
> >Since I was looking for a way to burn wood with blue flames, I violently
> >disagreed. This was in early 1980.
> >I am still looking.
> >
> >
> >>Because, judging by the responses about this topic, COMBUSTION
efficiency
> >>might not be of much concern at all.
> >
> >It is because, thankfully and in contrast to the early 80's, we now care
> >about the emissions.
> >
> >
> >>3. Therefore, Juntos gasifier and Rocket and any other
> >>"combustion-chamber-focused" stove are all about the same AS FAR AS
> >>COMBUSTION EFFICIENCY IS CONCERNED.
> >
> >If combustion efficiency is defined as: (thermal energy produced/
> >combustion value), then a similar figure for different stoves would
roughly
> >qualify them as equally polluting.
> >
> >>4. But the structures around Juntos or Rocket or many other combustion
> >>chambers ARE important for efficiency. (Is anyone working on
"structure"
> >>as being separate from the combustion chamber? Is there a "plancha"
> >>specialist in the audience -- who is not married to one of the specific
> >>combustion chamber modes?)
> >
> >For stoves that have no open or hidden agenda to produce charcoal as a
> >fringe benefit, the combustion chambers of the Rocket or the Downdraft
> >stove provide optimal conditions for complete combustion. Downstream from
> >the combustion chamber, structure is important to insure optimal heat
> >transfer to the food being processed (via whatever medium, be it griddle,
> >pan or oven). As soon as a better combustion chamber is discovered, I
will
> >divorce the Downdraft stove.
> >
> >>5. And do not forget the "cooking practices" variable, which is less
> >>quantitatively scientific and is more subjective and social, and heavily
> >>influences the efficiency of any "cooking station" (with fuel,
combustion
> >>chamber, and structure, as well as cooking practices).
> >
> >A good and versatile wood burning cookstove should be able to accomodate
a
> >large range of cooking practices. People in the industrialised world have
> >to make do with standard mass produced gas or electric cookstoves and
don't
> >seem to have much of a problem. The sticking point is "A good and
versatile
> >woodburning cookstove". At the moment there aint no such animal.
> >
> >>6. Therefore, in contrast with "COMBUSTION efficiency", can we have
> >>a concept like "heat-CAPTURE efficiency"?
> >>
> >>Please do not forget:
> >>Can you or anyone provide a "quotable quote" with full reference for
such
> >>a statement about combustion efficiency NOT meriting attention for small
> >>stove research or concern, by that professor or anyone else?
> >
> >Such a quote should be ignored or used to shoot or at least fire that
person.
> >
> >>Or maybe YOU want to provide such a statement to the Stoves list with
the
> >>intention that the rest of us can quote YOU as stating that "combustion
> >>efficiency" (as clearly defined by YOU) is not sufficiently important to
> >>merit much attention.
> >
> >I think I have clarified the matter.
> >
> >Smiling back,
> >
> >Piet
> >
> >
> >-
> >Stoves List Archives and Website:
> >http://www.crest.org/discussion/stoves/200204/
> >http://crest.org/discussiongroups/resources/stoves/
> >>
> >Stoves List Moderators:
> >Ron Larson, ronallarson@qwest.net
> >Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >>
> >List-Post: <mailto:stoves@crest.org>
> >List-Help: <mailto:stoves-help@crest.org>
> >List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
> >List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >>
> >Sponsor the Stoves List: http://www.crest.org/discuss3.html
> >-
> >Other Biomass Stoves Events and Information:
> >http://www.bioenergy2002.org
> >http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> >http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> >http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >>
> >For information about CHAMBERS STOVES
>
>>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.ht
m
> >
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> Rogério Carneiro de Miranda
> Director, Ecofogones y Reposición Forestal
> PROLEÑA/Nicaragua
> Apartado Postal C-321
> Managua, Nicaragua
> TELEFAX (505) 249 0116
> EMAIL: rmiranda@sdnnic.org.ni
> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
>
> -
> Stoves List Archives and Website:
> http://www.crest.org/discussion/stoves/200204/
> http://crest.org/discussiongroups/resources/stoves/
> >
> Stoves List Moderators:
> Ron Larson, ronallarson@qwest.net
> Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >
> List-Post: <mailto:stoves@crest.org>
> List-Help: <mailto:stoves-help@crest.org>
> List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
> List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >
> Sponsor the Stoves List: http://www.crest.org/discuss3.html
> -
> Other Biomass Stoves Events and Information:
> http://www.bioenergy2002.org
> http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
>
>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>

From elk at wananchi.com Wed May 22 02:41:39 2002
From: elk at wananchi.com (elk)
Date: Tue Aug 31 21:37:52 2004
Subject: Hello from Nairobi
Message-ID: <00e601c20185$ec4331e0$0247083e@default>

Hey- where has everyone gone? I'm posting this as a
test to determine whether I've been knocked off the list or if things are just
unusually quiet amongst us stovers.

All's well in Nairobi. Busy trying to meet the
increased demand for our Vendor's Waste Charcoal in response to the rainy season
and the Kenya Gov't ban on timber and charcoal harvesting in
forests.

rgds;
elk

--------------------------Elsen L.
Karstadelk@wananchi.com<A
href="http://www.chardust.com">www.chardust.comNairobi
Kenya

From pverhaart at optusnet.com.au Wed May 22 05:17:35 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:52 2004
Subject: Hello from Nairobi
In-Reply-To: <00e601c20185$ec4331e0$0247083e@default>
Message-ID: <5.1.0.14.2.20020523001433.00a5f1e0@localhost>

I am here and received your posting, so yes, you are still on the list, I
guess.
Peter Verhaart

At 14:43 22/05/02 +0300, you wrote:
Hey-
where has everyone gone? I'm posting this as a test to determine whether
I've been knocked off the list or if things are just unusually quiet
amongst us stovers.

All's well in Nairobi. Busy trying to meet the
increased demand for our Vendor's Waste Charcoal in response to the rainy
season and the Kenya Gov't ban on timber and charcoal harvesting in
forests.

rgds;
elk

--------------------------
Elsen L. Karstad
elk@wananchi.com
www.chardust.com
Nairobi Kenya

From tmiles at trmiles.com Wed May 22 06:43:12 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:52 2004
Subject: Fw: Boiling Point 48
Message-ID: <003201c201a7$2b9de710$6401a8c0@tommain>

Stovers,

A request from Liz Bates of ITDG. Please contact her directly.

Tom Mile

----- Original Message -----
From: "Liz Bates" <lizb@itdg.org.uk>
To: <stoves-owner@crest.org>
Sent: Wednesday, May 22, 2002 7:14 AM
Subject: Boiling Point 48

> Please could you post this for me - thank you
> Liz
>
> Boiling Point 48 will be going to the printers in the next few days. If
> anyone would like to promote any household energy work they are doing (in
a
> short paragraph) or any meetings, workshops, publications, happenings,
> funding opportunities, awards etc. that they would like to promote,
please
> let me have the details very soon. Don't forget to include your name and
> contact details. Realistically, things happening before July are unlikely
to
> reach the readers in time.
> If you do not receive the journal, and would like to do so, please let me
> know <lizb@itdg.org.uk>
>
> Many thanks
> Liz
>
> > Liz Bates
> > lizb@ITDG.org.uk
> > Intermediate Technology Development Group
> > Schumacher Centre for Technology Development
> > Bourton Hall
> > Bourton On Dunsmore
> > Warwickshire
> > CV23 9QZ
> > Tel: +44 - 01926 634400
> > Fax: +44 - 01926 634401
> > www.itdg.org
> >
> > Company Reg. No 871954, England
> > Charity No 247257
> >
> >
> >
> >
> >
> >
> >
> This email and any files transmitted with it are confidential and intended
> solely for the use of the individuals or entity to whom they are
addressed.
> ITDG and it subsidiaries(ITC and ITDG Publishing) cannot accept liability
or
> contractual inferences for statements which are clearly the senders own
and
> not made on behalf of ITDG or it subsidiaries(ITC and ITDG Publishing).
>
>

From andrew.heggie at dtn.ntl.com Wed May 22 23:23:32 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:52 2004
Subject: Hello from Nairobi
In-Reply-To: <5.1.0.14.2.20020523001433.00a5f1e0@localhost>
Message-ID: <9j7peucnhpgrt9ofjegba18njb7ggm0t8u@4ax.com>

On Thu, 23 May 2002 10:18:03 +0300, "elk" <elk@wananchi.com> wrote:

>But it still doesn't explain this deathly silence.......

I thought you were the busy one....

>> All's well in Nairobi. Busy trying to meet the increased demand for our Vendor's Waste Charcoal in response to the rainy season and the Kenya Gov't ban on timber and charcoal harvesting in forests.

It's an ill wind that blows nobody any good.
Anyway it's nice to see that your vendors waste briquettes are in
demand, I have tried some briquettes recently and find their slower
burning is good for spit roasting. I wonder if this is compensation
for all the clay that you have to buy with the charcoal.

Ronal is busy on projects local to him and has recently upgraded his
software which may explain his silence.

If Peter V has sourced the information that he thought would put his
downdraught barbecue up in the top right of the chart Kirk posted
perhaps we could discuss the attributes which the chart addresses.

I was very late in managing to see the chart because I could not
decode the powerpoint presentation so I have not commented on Kirk's
post till now. I can readily see it as a gif on the crest site.

The chart attempts to combine elements of combustion efficiency and
heat transfer.

Prasad hinted at the fact that combustion efficiency must not be seen
only as completeness of combustion because this can be achieved at the
expense of copious amounts of excess air. This raises the mass flow
and dilutes the temperature. This lower temperature has implications
for poor heat transfer. IMO the higher grade the fuel the lower excess
air required to reach an equilibrium which produces an acceptable
level of pollutants.

If we can build on the chart (which might be viewed as ascii art) we
should look at what factors will enable biomass stoves to get up in
the right hand top by considering what causes the stoves on the
original chart to score as they do.

I still fail to see how biogas (which I take to be a mixture of CO2
and methane) can better lpg (propane) in the chart, whereas I can see
that "natural" gas as delivered via the gas grid (nearly pure methane)
would be the best performer.

AJH with steam powered cookstove!

From psanders at ilstu.edu Thu May 23 04:33:15 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:52 2004
Subject: Hello from Nairobi
In-Reply-To: <5.1.0.14.2.20020523001433.00a5f1e0@localhost>
Message-ID: <4.3.1.2.20020523082640.018d7d70@mail.ilstu.edu>

ELK,

At least part of the silence is because many of us (maybe 30 people??)
are involved with applications to the Shell Foundation (I estimated 8
proposals from the Stovers people, but only about 4 have identified
themselves to the rest of the Stoves list.)

So, for example, I am having more "off-list" contact with Tom
Reed and others. We are not secretive, but many aspects are less
relevant to the whole list.

We are waiting for the 6 June date (or before) for Shell Foundation to
inform who is invited to make final formal proposals.

Unfortunately, the silence IS stifling the list communications. For
example, you mentioned the Kenya Government's change to prohibit wood and
charcoal taking from the forests. THAT information IS important to
me (and some others) who are focused on stoves that use "junk"
biomass instead of the full wood biomass.

I think the messages will increase again after the Shell Foundation makes
its announcements.

Paul

At 10:18 AM 5/23/02 +0300, elk wrote:
Thanks
Peter.

I'm still on the list! Hooray!

But it still doesn't explain this deathly
silence.......

elk

Paul S. Anderson, Ph.D., Fulbright Prof. to Mozambique 8/99 -
7/00
Rotary University Teacher Grantee to Mozambique >10 mo of
2001-2003
Dept of Geography - Geology (Box 4400), Illinois State
University
Normal, IL 61790-4400 Voice:
309-438-7360; FAX: 309-438-5310
E-mail: psanders@ilstu.edu - Internet items:
www.ilstu.edu/~psanders

From psanders at ilstu.edu Thu May 23 04:42:46 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:52 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <4.3.1.2.20020523084024.018d5270@mail.ilstu.edu>

At 09:14 AM 5/23/02 +0100, AJH wrote:

>Prasad hinted at the fact that combustion efficiency must not be seen
>only as completeness of combustion because this can be achieved at the
>expense of copious amounts of excess air. This raises the mass flow
>and dilutes the temperature. This lower temperature has implications
>for poor heat transfer. IMO the higher grade the fuel the lower excess
>air required to reach an equilibrium which produces an acceptable
>level of pollutants.

Please consider if the problem of "temperature dilution" (mentioned in the
above paragraph) would be less of a problem if the air entering was already
at a high temperature. And I mean at a VERY high temperature, as hot as
you can get it.

Has research been done on the impact of pre-heated primary and/or
pre-heated secondary air? Anyone have references?

Tom Reed was just here in Illinois, so he is on the road and will not get
this message for several days. While here he said that the denser (cooler)
air was better able to force its way into a body of gases than would warmer
air, meaning better mixing of air and gas if the air was cooler. I said to
Tom that I believe in the value of pre-heated air and therefore we need to
consider how to do better mixing. (Then he left, and the conversation
remains open.)

I would think this is pretty basic information that merits data collection
if data are not already available.

From psanders at ilstu.edu Thu May 23 05:12:06 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:52 2004
Subject: Stoves "Service-Discovery trip" to southern Africa
Message-ID: <4.3.1.2.20020523085115.018d5e40@mail.ilstu.edu>

Stovers,

I go to South Africa and Mozambique in early July until early October this
year. (University work and stoves work.)

I am organizing an "Service-Discovery trip" to that area for 2 weeks (13 to
28 July 2002) for some Rotarians (I am an active Rotarian). It is far more
than tourism. It is focused on issues of service and the participants will
get great exposure about several of the serious issues in Africa and other
developing areas. (The trip will include 3 days in the Kruger National
Park, an enjoyable place to see how the landscape was before the pressures
of the 20th Century.)

This group will include Tom Reed (plus myself as group leader) and others
who have serious interests in stoves. And one of our intended stops is in
Swaziland where Stover Crispin has his stoves and other applicable
technology. Other topics such as education and community development will
also be examined to the extent of the interest of the group members.

The estimated cost is US$4000, but there are some negotiable aspects to the
costs. This is a "non-profit" trip without paid guides. We have
tremendous contacts with the Rotarians in southern Africa, who will be
providing home-stay in several locations and providing transportation
assistance. Any "surplus funds" will go to appropriate charity work in
the areas we visit. Therefore, I believe that this message is not a
commercialization of our Stoves list serve.

Group size will be 8 to 16 people, and we still have room for a few more
people. It would be fun to have a few more "Stovers" in the group.

If interested, please contact me directly (off-list)
at psanders@ilstu.edu very soon for more details.

Paul

From tmiles at trmiles.com Thu May 23 05:43:11 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:52 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <003e01c20267$f572e570$0501a8c0@tomslaptop>

Paul, Andrew

Mixing gases of similar densities requires energy whether it is for primary
or secondary air. To conserve energy some designs concentrate small jets of
combustion air impinging on small areas of fuel. Good secondary air mixing
is also done with jets as Tom demonstrates in the burner "ring" of his
turbostove. (See photo at
http://crest.org/discussiongroups/resources/stoves/ ) We sometimes use
eductor or venturi designs for mixing. These also require energy to
penetrate and mix with combustible gases. It seems to me that the challenge
is to "blow on the fire" without using a bellows (external energy). To do
that you have to have a pressure differential or a temperature differential.

Tom Miles

----- Original Message -----
From: "Paul S. Anderson" <psanders@ilstu.edu>
To: "AJH" <andrew.heggie@dtn.ntl.com>; <stoves@crest.org>
Sent: Thursday, May 23, 2002 6:50 AM
Subject: Temperature dilution

> Has research been done on the impact of pre-heated primary and/or
> pre-heated secondary air? Anyone have references?
>
> Tom Reed was just here in Illinois, so he is on the road and will not get
> this message for several days. While here he said that the denser
(cooler)
> air was better able to force its way into a body of gases than would
warmer
> air, meaning better mixing of air and gas if the air was cooler. I said
to
> Tom that I believe in the value of pre-heated air and therefore we need to
> consider how to do better mixing. (Then he left, and the conversation
> remains open.)
>
> I would think this is pretty basic information that merits data collection
> if data are not already available.

From psanders at ilstu.edu Thu May 23 06:50:50 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:52 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <4.3.1.2.20020523104021.018dc4a0@mail.ilstu.edu>

At 07:41 AM 5/23/02 -0700, Tom Miles wrote:
>Paul, Andrew
>
>Mixing gases of similar densities requires energy whether it is for primary
>or secondary air. To conserve energy some designs concentrate small jets of
>combustion air impinging on small areas of fuel. Good secondary air mixing
>is also done with jets as Tom demonstrates in the burner "ring" of his
>turbostove. (See photo at
>http://crest.org/discussiongroups/resources/stoves/ ) We sometimes use
>eductor or venturi designs for mixing. These also require energy to
>penetrate and mix with combustible gases. It seems to me that the challenge
>is to "blow on the fire" without using a bellows (external energy). To do
>that you have to have a pressure differential or a temperature differential.
>
>Tom Miles

All,

1. Tom Reed is already "blowing on the fire" with his small fan in a gasifier.

2. If the increase in available energy (because of using HOT air) exceeds
the energy requirement to blow the hot air, then the net gain is to be desired.

3. If the pre-heating of the air is accomplished by the combustion
process, is the loss of energy (needed for air pre-heating) significant in
relation to the gain by using the pre-heated air to obtain better
combustion (via less temperature dilution)? Many variables here, including
the stove structure that pre-heats the air at the chimney-level (considered
to be mainly wasted heat except for needed draft) versus pre-heating closer
to the combustion chamber.

4. I have previously written about the 4 components or issues of stoves
: fuel, combustion chamber, physical structure, and the cooking
practices. But Tom Reed recently argued to me when we met that a 5th
component could be "air". I countered with a comment that "air is air" and
we assume it is available, and that the issues about air are really within
the issues of the combustion chamber and how it treats and delivers the
air. Air is essential, but I have not yet added it to the list of the 4
components. (Your thoughts would be appreciated on this topic.)

ELK, Are we getting back to our prior levels of communication?

From tmiles at trmiles.com Thu May 23 07:05:59 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:52 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <014901c20273$8e3f1a70$6401a8c0@tommain>

Paul,

If you are reducing the problem to a few components you should include
phlogiston, given to us in the 17th century by Johann Joachim Becher and
popularized by Georg Ernst Stahl. Phlogiston is "the matter and principle of
fire, contained in all metals and combustible bodies, and given up in
burning or calcination." (McCann, H. Gilman. Chemistry Transformed: the
Paradigmatic Shift From Phlogiston to Oxygen. Norwood: Ablex, 1978.)

There you have it all in one bundle.

Tom

----- Original Message -----
From: "Paul S. Anderson" <psanders@ilstu.edu>
To: "Tom Miles" <tmiles@trmiles.com>; "AJH" <andrew.heggie@dtn.ntl.com>;
<stoves@crest.org>
Sent: Thursday, May 23, 2002 8:58 AM
Subject: Re: Temperature dilution

> 4. I have previously written about the 4 components or issues of stoves
> : fuel, combustion chamber, physical structure, and the cooking
> practices. But Tom Reed recently argued to me when we met that a 5th
> component could be "air". I countered with a comment that "air is air"
and
> we assume it is available, and that the issues about air are really within
> the issues of the combustion chamber and how it treats and delivers the
> air. Air is essential, but I have not yet added it to the list of the 4
> components. (Your thoughts would be appreciated on this topic.)

From tombreed at attbi.com Fri May 24 02:52:07 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:52 2004
Subject: Air is Number 1!
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <001601c20316$2a1fdbd0$0680fd0c@TOMBREED>

Dear Paul, Tom and All:

Tom Miles hits it on the head. Phlogiston (oxygen) access is the most
important part of biomass combustion, gasification and stove design!
(Dephlogisticated air is the original name for the combustion gases exiting
your exhaust pipe, since the oxygen has been consumed, making a useful, hot,
non oxidizing gas. Try it for pyrolysis.)

I have a commercial stove that is dreadful because the air enters at the
wrong places - too much at bottom (releasing volatiles and gases too
quickly), not nearly enough at the top, so gases aren't burned before they
reach their target, the pot being heated. By rearranging the air holes it
burns beautifully inside the stove.

I find that most stove tinkerers tend to focus on materials of construction
first and principles last. This needs to be reversed. AIR CONTACT IS THE
MOST IMPORTANT PART OF STOVE DESIGN.

So, in stove design, first focus on the principles - how the pyrolysis will
occur, how the resulting gases will access oxygen, then worry about Paul's
four principles which are certainly also VERY important.

o fuel
o combustion chamber
o physical structure
o the cooking

(However, aren't combustion chamber and physical structure the same thing?)

Another MAJOR piece of the puzzle is water content (measured by weighing,
heating to 105C for an hour (depending on size), then reweighing. Wood with
30% moisture (jungle wood) is barely related to wood with 7% moisture
(Denver Dry).

Combustion of dry wood requires 6 kg of air for each kg of wood. For 30%
moisture wood it only requires 4.2 kg. Pyrolysis of dry wood requires < 1
kg air/kg wood; for 30% moisture wood pyrolysis requires 2 to 3 kg air/kg
wet wood.

So, principles first, application second will get us to a new generation of
cookstoves!

Yours truly, TOM REED
BEF STOVEWORKS

PS: I spent a day with Paul in Normal Illinois discussing all this and
seeing a battery of new kinds of stoves that he is making. Very ingenious.
There's a lot of room for inovation in solving the world stove problem, but
it has better start with the principles.

----- Original Message -----
From: "Tom Miles" <tmiles@trmiles.com>
To: "AJH" <andrew.heggie@dtn.ntl.com>; <stoves@crest.org>; "Paul S.
Anderson" <psanders@ilstu.edu>
Sent: Thursday, May 23, 2002 10:04 AM
Subject: Re: Temperature dilution

> Paul,
>
> If you are reducing the problem to a few components you should include
> phlogiston, given to us in the 17th century by Johann Joachim Becher and
> popularized by Georg Ernst Stahl. Phlogiston is "the matter and principle
of
> fire, contained in all metals and combustible bodies, and given up in
> burning or calcination." (McCann, H. Gilman. Chemistry Transformed: the
> Paradigmatic Shift From Phlogiston to Oxygen. Norwood: Ablex, 1978.)
>
> There you have it all in one bundle.
>
> Tom
>
> ----- Original Message -----
> From: "Paul S. Anderson" <psanders@ilstu.edu>
> To: "Tom Miles" <tmiles@trmiles.com>; "AJH" <andrew.heggie@dtn.ntl.com>;
> <stoves@crest.org>
> Sent: Thursday, May 23, 2002 8:58 AM
> Subject: Re: Temperature dilution
>
>
> > 4. I have previously written about the 4 components or issues of stoves
> > : fuel, combustion chamber, physical structure, and the cooking
> > practices. But Tom Reed recently argued to me when we met that a 5th
> > component could be "air". I countered with a comment that "air is air"
> and
> > we assume it is available, and that the issues about air are really
within
> > the issues of the combustion chamber and how it treats and delivers the
> > air. Air is essential, but I have not yet added it to the list of the 4
> > components. (Your thoughts would be appreciated on this topic.)
>
>
>
>
> -
> Stoves List Archives and Website:
> http://www.crest.org/discussion/stoves/200204/
> http://crest.org/discussiongroups/resources/stoves/
> >
> Stoves List Moderators:
> Ron Larson, ronallarson@qwest.net
> Elsen L. Karstad, elk@wananchi.com www.chardust.com
> >
> List-Post: <mailto:stoves@crest.org>
> List-Help: <mailto:stoves-help@crest.org>
> List-Unsubscribe: <mailto:stoves-unsubscribe@crest.org>
> List-Subscribe: <mailto:stoves-subscribe@crest.org>
> >
> Sponsor the Stoves List: http://www.crest.org/discuss3.html
> -
> Other Biomass Stoves Events and Information:
> http://www.bioenergy2002.org
> http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
>
>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>
>

From pverhaart at optusnet.com.au Fri May 24 03:00:05 2002
From: pverhaart at optusnet.com.au (Peter Verhaart)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <9j7peucnhpgrt9ofjegba18njb7ggm0t8u@4ax.com>
Message-ID: <5.1.0.14.2.20020524214305.00a46630@localhost>

Did Prasad really say: "it dilutes the temperature"? It gets mixed with
something else? Beyond me.

How would you go about getting air at a very high temperature? Remember
this is not rocket science. If it were we could pulverise the wood and
inject it entrained in a flow of air (preheated if necesary). If that is
not hot enough we take oxygen, automatic ignition, temperature and heat
output rate control, none of this a problem.

Alas, we stovers have to make do with what nature provides and we all know
nature is a poor provider. The best we can come up with is natural draft
and if we are really smart and inspired and lucky we might come up with
something that works.

I am sure, bye the way, that research on preheated air has been done for
industrial combustion systems. The air is not only preheated, it is also
given the right velocity to do its job, far beyond the capability of
natural draft.

Piet (ever cheerful) Verhaart

At 08:50 23/05/02 -0500, you wrote:
Please consider if the problem of "temperature dilution" (mentioned in the
above paragraph) would be less of a problem if the air entering was already
at a high temperature. And I mean at a VERY high temperature, as hot as
you can get it.

>Has research been done on the impact of pre-heated primary and/or
>pre-heated secondary air? Anyone have references?

From LINVENT at aol.com Fri May 24 06:10:27 2002
From: LINVENT at aol.com (LINVENT@aol.com)
Date: Tue Aug 31 21:37:53 2004
Subject: GAS-L: Air is Number 1!
Message-ID: <e5.1876aa38.2a1fb152@aol.com>

In a message dated 5/24/02 5:53:43 AM, tombreed@attbi.com writes:

<< Dear Paul, Tom and All:

Tom Miles hits it on the head. Phlogiston (oxygen) access is the most

important part of biomass combustion, gasification and stove design!

(Dephlogisticated air is the original name for the combustion gases exiting

your exhaust pipe, since the oxygen has been consumed, making a useful, hot,

non oxidizing gas. Try it for pyrolysis.)

I have a commercial stove that is dreadful because the air enters at the

wrong places - too much at bottom (releasing volatiles and gases too

quickly), not nearly enough at the top, so gases aren't burned before they

reach their target, the pot being heated. By rearranging the air holes it

burns beautifully inside the stove.

I find that most stove tinkerers tend to focus on materials of construction

first and principles last. This needs to be reversed. AIR CONTACT IS THE

MOST IMPORTANT PART OF STOVE DESIGN.

So, in stove design, first focus on the principles - how the pyrolysis will

occur, how the resulting gases will access oxygen, then worry about Paul's

four principles which are certainly also VERY important.

o fuel

o combustion chamber

o physical structure

o the cooking

(However, aren't combustion chamber and physical structure the same thing?)

Another MAJOR piece of the puzzle is water content (measured by weighing,

heating to 105C for an hour (depending on size), then reweighing. Wood with

30% moisture (jungle wood) is barely related to wood with 7% moisture

(Denver Dry).

Combustion of dry wood requires 6 kg of air for each kg of wood. For 30%

moisture wood it only requires 4.2 kg. Pyrolysis of dry wood requires < 1

kg air/kg wood; for 30% moisture wood pyrolysis requires 2 to 3 kg air/kg

wet wood.

So, principles first, application second will get us to a new generation of

cookstoves!

Yours truly, TOM REED

BEF STOVEWORKS

PS: I spent a day with Paul in Normal Illinois discussing all this and

seeing a battery of new kinds of stoves that he is making. Very ingenious.

There's a lot of room for inovation in solving the world stove problem, but

it has better start with the principles. >>

Dear Stovers,
Some time ago, I used the principal which Tom Reed described in building
a small stove for my mine cabin. A couple of criteria were the design basis,
one it would accept large wood, 2 ft. in length, and the other was that the
exhaust had no smoke. I accomplished both with a 55 gallon heavy walled drum
with an air preheater and injection of air at the right points. The gases
would combust in the exhaust pipe with an adjustment in air inlet at that
point and there was no smoke. It would run all night on one charge and keep
the cabin nice and warm in the coldest periods- to minus 20ËšF.
I used a hand cranked auger to discharge the ash. No grate.
Anyhow, sometime when it is possible to figure out how to make money on
this type of system, perhaps I will market it.

Sincerely,
Leland T. Taylor
President
Thermogenics Inc.
7100-2nd St. NW, Albuquerque, New Mexico 87107
phone 505-761-5633 fax 505-341-0424
Attached files are zipped and can be decompressed with <A
HREF="http://www.aladdinsys.com/expander/">www.aladdinsys.com/expander/ </A>

-
Gasification List Archives:
http://www.crest.org/discussion/gasification/200202/

From kchisholm at ca.inter.net Fri May 24 06:21:11 2002
From: kchisholm at ca.inter.net (Kevin Chisholm)
Date: Tue Aug 31 21:37:53 2004
Subject: GAS-L: Air is Number 1!
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <009601c20336$040be180$c619059a@kevin>

Dear Tom
----- Original Message -----
From: "Tom Reed" <tombreed@attbi.com>
To: "Tom Miles" <tmiles@trmiles.com>; "AJH" <andrew.heggie@dtn.ntl.com>;
<stoves@crest.org>; "Paul S. Anderson" <psanders@ilstu.edu>
Cc: "gasification" <gasification@crest.org>
Sent: Friday, May 24, 2002 8:28 AM
Subject: GAS-L: Air is Number 1!

> Dear Paul, Tom and All:
>
> Tom Miles hits it on the head.
...del...>

> I find that most stove tinkerers tend to focus on materials of
construction
> first and principles last.

And you hit it right on the head also with a very perceptive definition of a
stove tinkerer!! :-)

Kevin Chisholm

-
Gasification List Archives:
http://www.crest.org/discussion/gasification/200202/

From andrew.heggie at dtn.ntl.com Fri May 24 08:39:37 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <9j7peucnhpgrt9ofjegba18njb7ggm0t8u@4ax.com>
Message-ID: <nkjseusdu3604i46c7qav10mh6jl610kpj@4ax.com>

On Fri, 24 May 2002 21:58:18 +1000, Peter Verhaart
<pverhaart@optusnet.com.au> wrote:

>Did Prasad really say: "it dilutes the temperature"? It gets mixed with
>something else? Beyond me.

Prasad said:
"Two more remarks: the quantity of air to be used. Too much or too
little air
can hurt the efficiency as well as quality of combustion. That window
is
rather small. We have data on this. Hopefully it will get on the
website one
of these days."

I paraphrased:

"Prasad hinted at the fact that combustion efficiency must not be seen
only as completeness of combustion because this can be achieved at the
expense of copious amounts of excess air."

and went on to say:

"This raises the mass flow
and dilutes the temperature."
>
>How would you go about getting air at a very high temperature?

As I have said before temperature is dependant on the fuel cv and
minimising excess air, I doubt this is a good route to follow with the
stove building materials we are using as tincanium is unlikely to
survive temperatures above 700C.

> Remember
>this is not rocket science.

I bet it's pretty similar in the combustion conditions wrt
survivability of the combustion chamber.

> If it were we could pulverise the wood and
>inject it entrained in a flow of air (preheated if necesary). If that is
>not hot enough we take oxygen, automatic ignition, temperature and heat
>output rate control, none of this a problem.
>
>Alas, we stovers have to make do with what nature provides and we all know
>nature is a poor provider. The best we can come up with is natural draft
>and if we are really smart and inspired and lucky we might come up with
>something that works.

I disagree that the best we can come up with is natural draught but I
may be wrong. Forced draught seems to become a necessity with
difficult fuels.
>
>I am sure, bye the way, that research on preheated air has been done for
>industrial combustion systems. The air is not only preheated, it is also
>given the right velocity to do its job, far beyond the capability of
>natural draft.

Agree there
AJH

From andrew.heggie at dtn.ntl.com Fri May 24 08:40:13 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <c8kseug371hhsmedb5d5u9oh4iticfcu13@4ax.com>

On Thu, 23 May 2002 07:41:36 -0700, "Tom Miles" <tmiles@trmiles.com>
wrote:

>
>----- Original Message -----
>From: "Paul S. Anderson" <psanders@ilstu.edu>
>To: "AJH" <andrew.heggie@dtn.ntl.com>; <stoves@crest.org>
>Sent: Thursday, May 23, 2002 6:50 AM
>Subject: Temperature dilution
>
>
>> Tom Reed was just here in Illinois, so he is on the road and will not get
>> this message for several days. While here he said that the denser
>(cooler)
>> air was better able to force its way into a body of gases than would
>warmer
>> air, meaning better mixing of air and gas if the air was cooler.

Makes sense however it seems to me that cool air entering a reaction
can be just as bad at quenching the reaction as a cold surface. If the
flame subsequently reaches sufficient dwell time and temperature it
should make no difference. From my little experiments it looks like
flame holding becomes less significant if the combustion chamber
reaches ~650C. I believe this is the temperature at which most of the
volatiles have dissociated and spontaneous combustion occurs.

> I said
>to
>> Tom that I believe in the value of pre-heated air and therefore we need to
>> consider how to do better mixing. (Then he left, and the conversation
>> remains open.)

OK we agree preheated air has a value, it also has a cost: it requires
more power to circulate it for two reasons:
1 The pumping energy is higher
2 intuitively you are also working against gravity
3 it must remove heat from somewhere else in the system, the laws of
thermodynamics limit this to less than 100% efficiency so the loss may
not be worthwhile, I shall continue to look.
>>
>> I would think this is pretty basic information that merits data collection
>> if data are not already available.
>
>

>Paul, Andrew
>
>Mixing gases of similar densities requires energy whether it is for primary
>or secondary air. To conserve energy some designs concentrate small jets of
>combustion air impinging on small areas of fuel. Good secondary air mixing
>is also done with jets as Tom demonstrates in the burner "ring" of his
>turbostove. (See photo at
>http://crest.org/discussiongroups/resources/stoves/ ) We sometimes use
>eductor or venturi designs for mixing.

Tom you are preaching to the converted here, we have covered this
ground in the past, complexity adding to cost is why it has not been
pursued by people in the field.

Vernon Harris suggested to me some while back that a device used in
this mode is an aspirator. Tom Reed has mentioned the benefits of an
electric fan for micro mixing for better combustion. We have also
previously discussed how premixed secondary combustion leads to a
shorter flame. This enables a lower cook stove with implications of
better stability.

> These also require energy to
>penetrate and mix with combustible gases. It seems to me that the challenge
>is to "blow on the fire" without using a bellows (external energy). To do
>that you have to have a pressure differential or a temperature differential.

Again it all comes down to cost, Tom Reed finds the cost of
rechargeable batteries and possibly a solar panel low in his economy.
I see a possible alternative route without this hi tech need, however
even here I do not believe the cost will outweigh the advantage with a
"good" fuel, it might however mitigate the pollution problems when
burning a poor fuel.

I have yet to sit down and consider the energy cost of my aspirator.

AJH

From tmiles at trmiles.com Fri May 24 09:11:42 2002
From: tmiles at trmiles.com (Tom Miles)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <007a01c2034e$484db5e0$6401a8c0@tommain>

Andrew,

You have laudable aspirations. First, take a deep breath. :-)

The most practical solution for moving air has to come from the field. Can a
stack effect be used? When is a solar panel and a battery useful? When do
you lift a weight in the air and let gravity drive a fan or bellows? Is it
worth a treadle and a flywheel?

I'll be interested in the progress of your quest.

Tom

----- Original Message -----
From: "AJH" <andrew.heggie@dtn.ntl.com>
To: "Tom Miles" <tmiles@trmiles.com>
Cc: <stoves@crest.org>; "Paul S. Anderson" <psanders@ilstu.edu>
Sent: Friday, May 24, 2002 10:37 AM
Subject: Re: Temperature dilution

> I have yet to sit down and consider the energy cost of my aspirator.
>
> AJH
>

From rifa at advertisnet.com Fri May 24 10:10:39 2002
From: rifa at advertisnet.com (Richard & Faye)
Date: Tue Aug 31 21:37:53 2004
Subject: remove me please
Message-ID: <005801c20356$a2c845a0$1dabb0d8@richard>

I have requested that I be removed from this list following the guidelines I
received when I joined. I receive an auto reply stating that my address is
not on the list.

Why than am I continuing to receive posting. I last requested to be removed
in April.

Richard Salmons

From andrew.heggie at dtn.ntl.com Fri May 24 12:31:32 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <p5cteuojq96fm7aon1aahaj0ij8j95m538@4ax.com>

On Thu, 23 May 2002 10:58:12 -0500, "Paul S. Anderson"
<psanders@ilstu.edu> wrote:

>
>2. If the increase in available energy (because of using HOT air) exceeds
>the energy requirement to blow the hot air, then the net gain is to be desired.

Too simplistic, you must build in a factor for the "utility" of the
energy, a sort of heat opportunity cost. Electric energy for fans has
a far higher opportunity cost than heat for cooking.

AJH

From andrew.heggie at dtn.ntl.com Fri May 24 12:55:39 2002
From: andrew.heggie at dtn.ntl.com (AJH)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <4jdteuc7mv8831p6caasnhr54ikuujrfig@4ax.com>

On Fri, 24 May 2002 11:10:23 -0700, "Tom Miles" <tmiles@trmiles.com>
wrote:

>Andrew,
>
>You have laudable aspirations.
Punny!

> First, take a deep breath. :-)

BTDTGTTS and the cyanosis!
>
>The most practical solution for moving air has to come from the field. Can a
>stack effect be used?

Of course but difficult with a pot in the way, anyway what was the
effect ~1mm of water gauge per 30m??

>When is a solar panel and a battery useful?

remember to factor in the life of the battery, I would doubt you could
better a capital cost of better than USD0.5/kWhr.

> When do
>you lift a weight in the air and let gravity drive a fan or bellows?

I posted figure for this some months back.

>Is it
>worth a treadle and a flywheel?

Using a bicycle I suspect you would not better 100W per person, still
it may better your bellows, I like bellows but not for continuous use.
>
>I'll be interested in the progress of your quest.

I think I am getting there but the masses and orifices are not quite
matched yet. Mensuration is the problem at the moment, I am certain I
am not yet getting sufficient gain for the additional cost.

AJH

From psanders at ilstu.edu Fri May 24 15:14:53 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:53 2004
Subject: Temperature dilution
In-Reply-To: <4.3.1.2.20020523104021.018dc4a0@mail.ilstu.edu>
Message-ID: <4.3.1.2.20020524190033.01b38f00@mail.ilstu.edu>

>On Thu, 23 May 2002 10:58:12 -0500, "Paul S. Anderson"
><psanders@ilstu.edu> wrote:
>
> >
> >2. If the increase in available energy (because of using HOT air) exceeds
> >the energy requirement to blow the hot air, then the net gain is to be
> desired.

In reply, At 10:30 PM 5/24/02 +0100, AJH wrote:
>Too simplistic, you must build in a factor for the "utility" of the
>energy, a sort of heat opportunity cost. Electric energy for fans has
>a far higher opportunity cost than heat for cooking.
>
>AJH

Paul replies: I think I understand that and agree in the general
case. But the electric energy to operate a very small (perhaps 12 volt DC)
fan is SO SMALL, and in comparison, the heat energy from the burning of the
biomass is SO GREAT.

My original statement or implied question (above) is related to the GREAT
difference between the tiny bit of energy needed to do the blowing and the
(we hope) increase in energy from better burning of the biomass.

An extreme case would be to have a US$ 2 small fan with many months or
years of useful life and a 12-volt battery that is occasionally recharged,
which together make it possible to burn (in a gasifier or in some other
stove) some form of biomass that is otherwise literally waste product to be
thrown away. The heat is from the biomass. We are just trying to make it
possible to burn the biomass by providing a small fan.

Please note that my initial comment (at start of this message) was about
getting HOT air to be available via fans. But now the discussion by Andrew
and by me seems to be more "generic" about fans and their "opportunity
costs." I am interested in BOTH:

1. fans per se, and
2, the value of getting hot air into the combustion chamber.

Did this make more sense? I could easily be missing something.

From psanders at ilstu.edu Fri May 24 16:18:55 2002
From: psanders at ilstu.edu (Paul S. Anderson)
Date: Tue Aug 31 21:37:53 2004
Subject: Air is Number 1!
In-Reply-To: <00e301c2022a$84746de0$5f47083e@default>
Message-ID: <4.3.1.2.20020524192321.01c38780@mail.ilstu.edu>

Tom R, Tom M, and all,

Tom R's message is left below for reference. (and Tom needs to forward
this to the gasification list because I cannot post to that list.)

First, I agree that we start with the principles!!!!!!!! And all of the
principles I know about stoves and gasification I learned from Tom Reed, or
on the Stoves list, or a little at Boy Scout camp.

Second, Tom wrote:
> AIR CONTACT IS THE MOST IMPORTANT PART OF STOVE DESIGN.
>
>So, in stove design, first focus on the principles - how the pyrolysis will
>occur, how the resulting gases will access oxygen, then worry about Paul's
>four principles which are certainly also VERY important.
>
>o fuel
>o combustion chamber
>o physical structure
>o the cooking
>
>(However, aren't combustion chamber and physical structure the same thing?)

No, they are NOT the same.

Structure (physical structure) of a stove includes things like legs, and
oven, and plancha, and pot-insert holes, ventilation that is not primarily
for increased draft, and where you place the combustion chamber.

The combustion chamber is where the burning takes place. And therefore,
the construction of the combustion chamber DOES include the issue of how to
get the air into the right places at the right time in the right amounts.

Physical structure and combustion chamber are VERY DIFFERENT, but we must
be aware of one as we develop the other, or we will get into trouble quickly.

I believe there is no confusion about what is meant by "fuel" and by
"cooking" as being two other components for consideration when doing stove
development.

Back to the issue of "air" and Tom's statement that "AIR CONTACT IS THE
MOST IMPORTANT PART OF STOVE DESIGN". I agree!!!!!!!!

But that air contact takes place where? It takes place in and around the
combustion chamber.

However, as I think further about air, I realize that all air is NOT the
same. The air in Illinois (650 feet above sea level, humid in summer) and
the air in Denver (5200 feet ASL and "Denver dry") are not the same air.

Also, a unit of preheated secondary air at 400 degrees F is not the same
air as the exact same molecules as a unit prior to being preheated.

Now the question is: Do we as stove designers make an issue of "aires"
(plural) like we make an issue of "fuels" (plural)? Or can the "combustion
chamber" attributes actually incorporate the issues about "air" being
pre-heated or fan-forced or something?

Let us not neglect the importance of air. Air is like fuel: If either air
or fuel is absent, there will not be any combustion. Now THAT is a
principle!!! (See, Tom, you have taught me well.)
(Smile).

Well, I just now thought that I should modify my list of components to become:

combustion materials (fuels and air)
combustion chamber (generating energy from the combustion materials)
structure (holding together the physical parts in a usable way)
cooking (getting use from the "stove", such as pot-configurations for
socially-defined methods of cooking, to also include space-heating if needed)

Please let me re-phrase those 4 components:

stove combustion materials (fuels and air)
stove combustion chamber (generating energy from the combustion materials)
stove structure (holding together the physical parts in a usable way)
stove cooking (getting use from the "stove", such as pot-configurations for
socially-defined methods of cooking, to also include space-heating if needed)

I hope that this has helped clarify why I have separated the issues of
stoves development
into 4 components.

Interestingly, those of us on the Stove list serve have our own specialties
in the 4 components. Many are combustion chamber specialists. Others are
fuels people. A smaller number are into the structure issues. And a few
(anybody??) on the Stoves list are focused on the cooking issues. And yet
we all seek "stove" improvement.

Have a good weekend !!
(or if you do not read this until you are back at work, I hope you had a
good weekend.)

Paul

At 05:28 AM 5/24/02 -0600, Tom Reed wrote:
>Dear Paul, Tom and All:
>
>Tom Miles hits it on the head. Phlogiston (oxygen) access is the most
>important part of biomass combustion, gasification and stove design!
>(Dephlogisticated air is the original name for the combustion gases exiting
>your exhaust pipe, since the oxygen has been consumed, making a useful, hot,
>non oxidizing gas. Try it for pyrolysis.)
>
>I have a commercial stove that is dreadful because the air enters at the
>wrong places - too much at bottom (releasing volatiles and gases too
>quickly), not nearly enough at the top, so gases aren't burned before they
>reach their target, the pot being heated. By rearranging the air holes it
>burns beautifully inside the stove.
>
>I find that most stove tinkerers tend to focus on materials of construction
>first and principles last. This needs to be reversed. AIR CONTACT IS THE
>MOST IMPORTANT PART OF STOVE DESIGN.
>
>So, in stove design, first focus on the principles - how the pyrolysis will
>occur, how the resulting gases will access oxygen, then worry about Paul's
>four principles which are certainly also VERY important.
>
>o fuel
>o combustion chamber
>o physical structure
>o the cooking
>
>(However, aren't combustion chamber and physical structure the same thing?)
>
>Another MAJOR piece of the puzzle is water content (measured by weighing,
>heating to 105C for an hour (depending on size), then reweighing. Wood with
>30% moisture (jungle wood) is barely related to wood with 7% moisture
>(Denver Dry).
>
>Combustion of dry wood requires 6 kg of air for each kg of wood. For 30%
>moisture wood it only requires 4.2 kg. Pyrolysis of dry wood requires < 1
>kg air/kg wood; for 30% moisture wood pyrolysis requires 2 to 3 kg air/kg
>wet wood.
>
>So, principles first, application second will get us to a new generation of
>cookstoves!
>
>Yours truly, TOM REED
>BEF STOVEWORKS
>
>PS: I spent a day with Paul in Normal Illinois discussing all this and
>seeing a battery of new kinds of stoves that he is making. Very ingenious.
>There's a lot of room for inovation in solving the world stove problem, but
>it had better start with the principles.

From dstill at epud.net Fri May 24 18:51:54 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:53 2004
Subject: Carbon balance guesstimate for wood
Message-ID: <002701c32123$784a19c0$9c1d66ce@default>

Dear Stovers,

Our friends at Colorado State are preparing to do tests on the Rocket type
cooking stove and I need info for them.... Their question is: Does anyone
have a Carbon balance for kiln dried Douglas fir? Or an equivelent Carbon,
Hydrogen, Water, Ash %mass breakdown?

THANKS,

Dean

From crispin at newdawn.sz Fri May 24 23:49:10 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:53 2004
Subject: Carbon content
Message-ID: <000e01c203c9$e797f2c0$2a47fea9@md>

Dear Dean

I did find the following analyses done by
Gottlieb:

C
H
N
O
Ash
Calories B.t.u.
Oak
50.16 6.02
0.09
43.36 0.37 4620 8316
Ash
49.18 6.27
0.07
43.91 0.57
4711 8480
Elm
48.99
6.20 0.06
44.25
0.50 4728
8510
Beech 49.06
6.11 0.09
44.17
0.57 4774
8591
Birch
48.88 6.06
0.10
44.67 0.29
4771 8586
Fir
50.36 5.92
0.05
43.39 0.28
5035 9063
Pine
50.31 6.20
0.04
43.08 0.37
5085 9153

Regards
Crispin

From dstill at epud.net Sat May 25 08:05:43 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:53 2004
Subject: Carbon content/two pot sunken stove
Message-ID: <002401c32290$cc98b220$5e1d66ce@default>

Dear Crispin,

Thanks very much for the info on wood! I really appreciate
your finding this so quickly and it does help move things ahead at Colorado
State. You are a gentleman and a scholar.

Peter Scott, Aprovecho consultant, and I have been working on
sunken two pot stoves for about a month now getting him ready to go to South
Africa to teach. I posted a photo of one of the first prototypes a while back.
In this type of stove two pots are sunk down to the level of the handles and a
seal is made there in a sheet metal top so that all smoke remains in the stove
and exits from a chimney. The benefits are that fuel efficiency rises
dramatically as much more pot surface area is exposed to direct heat. Also the
destructive heat, above say 900F. or so, is hitting the pots not a griddle so
after a bit of design help even sheet metal should last a while. The second pot
can boil at about the same time as the first if the heat contacts both pots
simultaneously. Or if desired, heat can be directed, in our case in a Rocket
combustion chamber, to the first pot which then boils faster leaving enough heat
to simmer sauces in the second pot. Provision can be made as well to lift the
pots to set levels exposing less of the pot to heat which is a secondary heat
control besides feeding less wood into the fire. Depending on pot size this type
of stove scores between 40 to 50% efficiency, using sheet metal (or tincanium),
vermiculite, wood ash, insulation, and forcing heat to pass the pots in
1/2" gaps. Peter created a oven that lies under the range from a five
gallon square tin can. Heat is shunted around three sides of the can in a sheet
metal one inch high duct, surrounded by insulation on all sides. A sliding door
of sheet metal shuts the passage between the two pots forcing heat to follow the
contour of the oven before exiting.

The negative side of such a stove is that the cold pots quench
the fire creating soot and more smoke, as pointed out by Kirk Smith and Grant
Ballard-Tremeer. I found that it was necessary to add much more air than usual
to reduce smoke. Also using a higher than usual Rocket combustion chamber helps,
say 14" instead of 10". This reduces over all efficiency but since
heat transfer is so good it seemed like a good compromise to get cleaner
burning. To avoid condensing harmful particles on enlarged pot surfaces it seems
necessary to pay more attention to cleaning up combustion
primarily.

I'll take a few photos of how the stove was constructed and
post them here.

Best and thanks to Crispin once again,

Dean
<BLOCKQUOTE
style="BORDER-LEFT: #000000 solid 2px; MARGIN-LEFT: 5px; PADDING-LEFT: 5px">
-----Original Message-----From:
Crispin <<A
href="mailto:crispin@newdawn.sz">crispin@newdawn.sz>To:
Stoves <<A
href="mailto:stoves@crest.org">stoves@crest.org>Date:
Saturday, May 25, 2002 1:48 AMSubject: Carbon
content
Dear Dean

I did find the following analyses done by
Gottlieb:

C

H
N
O
Ash Calories
B.t.u.
Oak
50.16 6.02
0.09
43.36 0.37 4620 8316
Ash
49.18 6.27
0.07
43.91 0.57
4711
8480
Elm
48.99
6.20 0.06
44.25
0.50 4728
8510
Beech 49.06
6.11 0.09
44.17
0.57 4774
8591
Birch
48.88 6.06
0.10
44.67 0.29
4771
8586
Fir
50.36 5.92
0.05
43.39 0.28
5035
9063
Pine
50.31 6.20
0.04
43.08 0.37
5085
9153

Regards
Crispin

From crispin at newdawn.sz Sat May 25 11:35:23 2002
From: crispin at newdawn.sz (Crispin)
Date: Tue Aug 31 21:37:53 2004
Subject: Carbon content/two pot sunken stove
Message-ID: <001301c2042b$1116b1c0$5ee80fc4@home>

Dear Dean

I was making a mud stove with a steel top pretty much as you describe at
TATU in Transkei about 20 years ago (time flies!) and it worked well with
two cast iron pots. The only thing different from what you describe is that
we did not use Rocketry principles.

I feel that a significant improvement can be made to the Rocket stove with
the provision of preheated secondary air though I have not drawn it out for
anyone to build. I am otherwise occupied at the moment designing a 5 ton
dumper for labour based road construction in Namibia and Tanzania. I will
get to it eventually.

If the hot secondary air was incorporated I feel that the extension in
height would not be necessary, or at least a lot of it could be removed and
you would still get little chilling and soot. It is possible of course to
preheat the primary air. Tom Reed has one of our latest stoves at the
moment and under medium-high power conditions the primary is heated
significantly. It can burn dense fuel well.

A marriage of the Basintuthu and the Rocket would solve most of your
remaining problems.

The 1/2" gap should not be a continuous, smooth one. though. It needs
little chambers similar to the ones I described for the evenly heated
rectangular plancha.

Regards
Crispin

From dstill at epud.net Sat May 25 16:15:36 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:53 2004
Subject: Carbon content/two pot sunken stove
Message-ID: <000401c322a9$209a33e0$d71d66ce@default>

Dear Crispin,

This is why I greatly appreciate this list, meaningful collaboration toward
progress! Thank you.

I agree that preheated primary air would possibly be very helpful to better
combustion in the Rocket stove. Let's chat about primary air first and then
in the natural course get to secondary air. I've tried to preheat primary
air for a while now. It is on my list of Unsolved Design Problems that I
hand out to students to gnaw on. The best that I've come up with is the fire
before the fire approach which I'm told has been used in large scale kilns
and producer gas making schemes, drawing air over coals and switching back
and forth between two fuel magazines. I'm limiting my thinking to natural
draft, because the world's that we work in are not yet at electrical fan
stage. Once a bed of coals is established there are maze like configurations
that would force hot flue gases into closer contact with glowing coals. I've
tried two or three of these approaches without noticing vast improvements. A
downdraft downfeed fuel magazine where the wood is vertical and burns at the
bottom tips preheats primary air a bit and it is a cleaner arrangement but
folks don't seem to like having their fire at the bottom of a well. So, I'd
love to have someone figure out how to substantially preheat primary air to
say 1,000F. That should make any stove much cleaner burning, I would
imagine.

As far as heating secondary air goes then don't we often run into the
problem of creating top feeding? The natural draft Z stove (top feeding)
used natural draft to pull air past the metal cylinder of the combustion
chamber and made nice blue jets of flame as the hot air entered the flame at
right angles. When you try the same arrangement with an open horizontal feed
magazine (which is what folks seem to want in Cental America) the effect is
less noticeable, I guess because most of the air is flowing in the
horizontal hole. If you have a strategy that includes horizontal feed I'll
very gladly try it and see what happens. I don't know if we need more air
above the fire or not. Is the fire starved at that point or does enough
excess air flow in that added air might not be needed? I'll refer that
question to the experts at Colorado State Engine Lab. Hopefully they can
answer this question for us...

Be grateful for any help,

Dean

From dstill at epud.net Sun May 26 16:17:50 2002
From: dstill at epud.net (Dean Still)
Date: Tue Aug 31 21:37:53 2004
Subject: Complete Rocketry
Message-ID: <000301c32310$d20074c0$2a1d66ce@default>

Dear Friends,

I'm doing a class for three people working with stoves starting June 10 for
a week or so. If anyone would like to attend we will be studying, discussing
and building cooking stoves, heating stoves, and a bread oven. Located at
Aprovecho, 20 miles south of Eugene, Oregon. For more info, please contact
me.

Best,

Dean

From tombreed at attbi.com Tue May 28 02:04:15 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:53 2004
Subject: Air Preheat over rated...
In-Reply-To: <9j7peucnhpgrt9ofjegba18njb7ggm0t8u@4ax.com>
Message-ID: <011601c20634$29a795f0$0680fd0c@TOMBREED>

Dear Ever Cheerful Piet and All:

Air preheat is a nice qualitative idea, warm and fuzzy, but when you get to
the quantitative use, watch out.

First, air passing over a hot surface has a low heat transfer coefficient,
so unless you measure its temperature just before combustion, you may only
gain a few percent of what you wish for.

Secondly, hot air is harder to move with natural or forced convection - it
is more viscous and lower density.

Third, hot air doesn't penetrate a mass of hot gas nearly as well as dense
cold air.

I don't pretend to know all the aspects, but I am very leary of glib
qualitative principles.

Caveat Emptor...

TOM REED BEF STOVEWORKS BEF GASWORKS
----- Original Message -----
From: "Peter Verhaart" <pverhaart@optusnet.com.au>
To: "Paul S. Anderson" <psanders@ilstu.edu>
Cc: <stoves@crest.org>
Sent: Friday, May 24, 2002 5:58 AM
Subject: Re: Temperature dilution

> Did Prasad really say: "it dilutes the temperature"? It gets mixed with
> something else? Beyond me.
>
> How would you go about getting air at a very high temperature? Remember
> this is not rocket science. If it were we could pulverise the wood and
> inject it entrained in a flow of air (preheated if necesary). If that is
> not hot enough we take oxygen, automatic ignition, temperature and heat
> output rate control, none of this a problem.
>
> Alas, we stovers have to make do with what nature provides and we all know
> nature is a poor provider. The best we can come up with is natural draft
> and if we are really smart and inspired and lucky we might come up with
> something that works.
>
> I am sure, bye the way, that research on preheated air has been done for
> industrial combustion systems. The air is not only preheated, it is also
> given the right velocity to do its job, far beyond the capability of
> natural draft.
>
> Piet (ever cheerful) Verhaart
>
>
> At 08:50 23/05/02 -0500, you wrote:
> Please consider if the problem of "temperature dilution" (mentioned in the
> above paragraph) would be less of a problem if the air entering was
already
> at a high temperature. And I mean at a VERY high temperature, as hot as
> you can get it.
>
> >Has research been done on the impact of pre-heated primary and/or
> >pre-heated secondary air? Anyone have references?
>
>
> -
> Stoves List Archives and Website:
> http://www.crest.org/discussion/stoves/200204/
> http://crest.org/discussiongroups/resources/stoves/
> >
> Stoves List Moderators:
> Ron Larson, ronallarson@qwest.net
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> >
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> -
> Other Biomass Stoves Events and Information:
> http://www.bioenergy2002.org
> http://www.crest.org/articles/static/1/1010424940_7.html Bioenergy
> http://www.crest.org/articles/static/1/1011975339_7.html Gasification
> http://www.crest.org/articles/static/1/1011975672_7.html Carbon
> >
> For information about CHAMBERS STOVES
>
>http://www.repp.org/discussiongroups/resources/stoves/Chambers/Chambers.htm
>
>

From stoves at ecoharmony.com Thu May 30 01:56:04 2002
From: stoves at ecoharmony.com (Grant Ballard-Tremeer)
Date: Tue Aug 31 21:37:53 2004
Subject: event and resource
Message-ID: <13210367078.20020530115441@ecoharmony.com>

Dear Stovers,

The HEDON Household Energy Network will be holding it's 11th meeting
in Johannesburg, South Africa from 27 to 28 August, coinciding with
the World Summit on Sustainable Development. Stovers may be interested
in attending. Further details are available on the HEDON website
www.ecoharmony.net/hedon/meeting or by emailing me at
stoves@ecoharmony.com

Some time ago I mentioned that an extensive online bibliography of
household energy literature was being developed. This is now available
at www.sparknet.info - the database currently contains searchable
details of over 300 articles, books and reports (including brief
descriptions) on a variety of household energy topics. If you would
like to add items to the database (your own articles and reports, or
literature you personally find useful for example), let me know and
I'll email you the simple forms for submitting the data. The database
is part of SPARKNET, a recently established Knowledge Network on
Household Energy in Southern and East Africa - more details available
at the sparknet.info website.

Regards
Grant

--
Grant Ballard-Tremeer PhD, visit ECO Ltd on the web at http://ecoharmony.com
64C Fairholme Road, W14 9JY, London
Tel +44-(0)20 7386 7930
Fax +44-(0)870 137 2360 and +44-(0)70 9236 7695
email stoves@ecoharmony.com
HEDON Household Energy Network http://ecoharmony.net/hedon
SPARKNET Knowledge Network in Southern and East Africa http://sparknet.info
HEDON on Agenda 21 and the World Summit http://ecoharmony.net/agenda21
-------------------

From tombreed at attbi.com Thu May 30 03:47:47 2002
From: tombreed at attbi.com (Tom Reed)
Date: Tue Aug 31 21:37:53 2004
Subject: Wood is wood, biomass is biomass, check the density
In-Reply-To: <000e01c203c9$e797f2c0$2a47fea9@md>
Message-ID: <00be01c207d4$fd696840$0680fd0c@TOMBREED>

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BioEnergy Lists: Improved Biomass Cooking Stoves

May 2002 Biomass Cooking Stoves Archive