[Terrapreta] Net Present Value and Net Future Value ofTPBenefits

[Duane Pendergast]

Good points Greg and April.

 

Life cycle CO2 emissions are something I've dabbled with. Figure two in the
following paper presents a plot of CO2 emissions (grams/kWhr) for various
means of producing electricity. Note there is a very wide range given in the
figure as local implementations of these technologies have more or less
dependence on fossil fuel in the overall process.  Note that wind releases
are estimated to be from 11 to 75 gms/kWhr. Solar Photovoltaic is estimated
at 30 to 279 gms/kWhr. Coal is from 960 to 1290 gms/kWhr based on relatively
ancient coal technology. 

 

 
http://www.computare.org/Support%20documents/Publications/CO2%20Free%20Cars.
htm

 

          I also looked into emissions from CANDU reactors in comparison
with alternatives once upon a time.

 

 
http://www.computare.org/Support%20documents/Publications/Life%20Cycle.htm

 

CANDU reactors are low on the nuclear reactor CO2 emission scale because
they use natural uranium and nuclear energy has been used to extract heavy
water for use as a coolant and moderator. The CO2 emissions from CANDU are
thus only about 3.2 grams/kWhr. 

 

Duane

 

          

 

-----Original Message-----
From: terrapreta-bounces at bioenergylists.org
[mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Greg and April
Sent: March 15, 2008 7:51 PM
To: Terra Preta
Subject: Re: [Terrapreta] Net Present Value and Net Future Value
ofTPBenefits

 

While very commendable, I highly doubt that ceasing the use of fossil fuels
or the use of cement will ever happen.

 

I say this as even the renewable energy industry requires the large use of
fossil fuel to make those wonderful products that make renewable energy
industry even possible.    Where does the raw materials come from the make a
wind generator or a solar cell - do you see what I'm trying to say?    

 

This is why I have traditionally asked what the carbon footprint of a MW
wind generator or a field of solar cells is - and no one that has advocated
such forms of energy over fossil fuels has ever been able to reply with any
thing more than " I don't know but it's smaller than traditional energy
sources ".    Then when I ask " How do you know? " all I get is silence.

 

The point I'm trying to make, is that it takes allot of fossil fuel to make
solar cells or a wind generator, so you can't just do without it when making
such products - just not possible.

 

 

Cement is a fact of life, and in many ways can not be done without, indeed
even the renewable energy industry needs it almost as much as fossil fuel.
I also do not see the issue with CO2 release with cement making as it is
temporary, since while CO2 is driven off to make the lime for the cement,
the cement absorbs CO2 as it cures.    Granted it does take more time to
absorb it than it did to drive it off, but it does happen - recall the
problems with Biosphere 2 and how they had to import O2 during the great
experiment - that was because the cement that was used for the construction
of the facility, was absorbing it from the air, and they failed to take that
into account and make sure that there was enough CO2 available for the
plants to use and the cement to absorb.

 

 

Greg H.

   

----- Original Message ----- 

From: Sean K. Barry <mailto:sean.barry at juno.com>  

Sent: Saturday, March 15, 2008 13:49

Subject: Re: [Terrapreta] Net Present Value and Net Future Value of
TPBenefits

 

SNIP

 

Terra Preta formation can address the multiple purposes; climate mitigation,
food production, and a viable energy resource.  I think this model works for
how to behave in the future with respect to energy and the environment.  The
immediate problem of high GHG concentrations in the atmosphere can be dealt
with by sequestering charcoal-in-soil and ceasing the production and use of
industrial fertilizers, burning of fossil fuels, and maybe of limestone
cement.  Charcoal-in-soil can lead to long term agricultural benefits,
lasting thousands of years (similar to the Amazonian TP formations, which
are found circa 4500 after formation began on them).  The process of making
charcoal from biomass can be a co-product with harvesting usable heat and
chemical energy in gaseous fuels from biomass.  The gaseous and liquid
chemicals extracted from pyrolysis of biomass can also or otherwise be
refined and used to produce even, again, industrial fertilizers and other
chemical products like those from petro-chemicals.

 

 

Regards,

 

SKB

----- Original Message ----- 

From: Richard Haard <mailto:richrd at nas.com>  

To: Kevin <mailto:kchisholm at ca.inter.net>  Chisholm 

Cc: Peter Read <mailto:peter at read.org.nz>  ; Sean
<mailto:sean.barry at juno.com>  K. Barry ; Miles Tom
<mailto:terrapreta at bioenergylists.org>  ; Toch Susan
<mailto:anaturalresource at gmail.com>  ; Michael Pilarski
<mailto:friendsofthetrees at yahoo.com>  ; Baur Hans <mailto:hans at riseup.net>
; Todd Jones <mailto:tjones at nas.com>  ; Terrapreta
<mailto:terrapreta at bioenergylists.org>  

Sent: Saturday, March 15, 2008 11:12 AM

Subject: Re:-----and Net Present Value of TP Benefits

 


On Mar 14, 2008, at 8:47 PM, Kevin Chisholm wrote:

> Peter Read wrote:


Hello Kevin  - drifting a bit from the thread but an interesting topic  
to me.

by NPV you mean direct value to farmer such as added CEC  or OM  
equivalent? The real value to farmer - not discounted carbon credit is  
what will make this all happen as general practice in agriculture.

What is the real economic benefit to the farmer per ton applied to  
land will depend on  soil type, climate and needs for fertilizer  
supplements to maintain fertility levels and as yet unquantified  
benefits of charcoal additive in soil. This figure of NPV $50  could  
be quite higher.

Most important in soils where organic matter needs to be monitored  
carefully to maintain productive capacity (not all do), what needs to  
be calculated is the cost of raising soil organic matter an equivalent  
amount permanently.  Ie the cost in lost production of fallow periods  
and the cost of reestablishing farming if the land has gone back to  
forest during fallow.

I am hoping the block research currently underway at our farm  
comparing compost to charcoal to fertilizer and permutations will  
answer this question for us at 4CN.

In our farming we are holding organic matter at 4 % minimum with  
biannual applications of 1 cubic yard of compost made from sewage  
solids and sawmill wood waste per 1000 sq. feet. In addition, we are  
adding summer and winter cover cropping when a particular section is  
fallow. So far as a OM supplement sawdust alone will do the job when  
balanced with garden fertilizer to compensate for binding of N and P  
by the decomposing wood. But this OM benefit in tilled soil is gone in  
a few years whereas the charcoal lasts as I am trying to quantify at  
our soil.

Buying charcoal at $ 200/ton will not happen for us in the short term  
anyway because of these economic factors. I do not know what a cubic  
yard of dry sawdust weighs but cost is  most likely 5 % or less and we  
use about 250 yards or more  annually. What might happen though in the  
near term is our on farm waste wood summer dried and converted to  
charcoal by some sort of smothered combustion. In our climate dry  
weather July through September will allow us to do this by windrowing  
with farm machinery.

We will have significant quantities available, probably each year 300  
cubic yards of loose twigs, roots and reject plant trimmings. Right  
now we either burn this stuff or use the soil/weed and reject plants  
as fill. Labor and use of equipment on farm does not equate to  
purchases outside of normal operations hence costs we incur on such a  
project are more easily absorbed as I suppose they are elsewhere. I am  
thinking some sort of buried pyrolysis with movable scrap sheet metal  
and wet spoiled hay in a top lit bottom draft system similar to our  
project 2 years ago.

If the value of farm waste worked into soil, say corn or wheat  is  
higher when converted to charcoal then the most efficient method for  
doing this onsite will rule in the end.


On Mar 14, 2008, at 8:47 PM, Kevin Chisholm wrote:
>  If we assume that Charcoal in TP gives a return with aNet Present  
> Value  equivalent to $50 per tonne of Charcoal applied,




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