[Terrapreta] Yet another Terra preta (ish) news clip

[Michael Bailes]

 Uppsula, Sweden
http://www.energycentral.com/centers/energybiz/ebi_detail.cfm?id=527

*The Algae Attraction - June 11,
2008<http://www.energycentral.com/site/newsletters/ebi.cfm?id=520>
*

Here's a link to the National Algae Association. It formed earlier this year
to share information about this alternative feedstock in response to the
interest expressed by biodiesel producers faced with increasing commodity
prices.

 http://www.nationalalgaeassociation.com/

You may wish to get more information about the ability of this technique to
capture CO2. The estimates I've seen hold that algae will capture over 90%
of the CO2 from coal fired exhaust where it is at 13.5% concentration that
is typical.

Up to 1/2 of the carbon can be inexpensively recycled directly to biodiesel
from lipids squeezed from the harvest (and burned cleanly in the boiler at
times when that is advantageous) - what's left over is called "press cake".
In addition to using it for high value animal feed or fermenting it to
ethanol, there's an intriguing possibility of producing a charcoal based
low-runoff "terra preta" fertilizer using pyrolization that captures
nitrogen from the syn-gas effluent and stores it the carbon matrix (that
also provides protective habitat from pesticides for nitrogen fixing soil
bacteria).

Because the nutrients do not wash out during irrigation, if this product
were widely adopted in the watershed, downstream rivers and bays (such as
the Chesapeake that is suffering from agricultural run-off) would be freed
from the cause of algal blooms that are currently choking many of them. And
because it persists in in the soil indefinately, virtually all of the carbon
produced for generation would be captured in the fuel cycle or sequested in
the ground.

You alluded to it in the article but when you look at the numbers, the
reality of how much faster algae grows is stunning. For comparison, growing
corn for ethanol yields 100 gallons per acre per year. Depending on the
strain that's cultivated, algae will yield between 4 and 30 THOUSAND gallons
per acre per year.

The more I learn about this practice the better it looks - the only trick is
figuring out how to cultivate algae effectively. It appears that where it
has ready access to a CO2 source this crop will be profitable even without
cap & trade credits. And then it appears very likely that that the regime
will be established starting next year. It doesn't take 20/20 foresight to
see how valuable algal carbon capture will be for operators and that there's
nothing in second place - I'm surprised that there aren't more and more
aggressive projects under way now.

Jeff Sutter

Step back and look at algae to capture CO2 emissions. There are 4 logic
problems:

1. It will not be 100% effective; some percentage of the CO2 will not be
captured, so we are looking at the potential to reduce, but not stop CO2
emissions from coal.

2. This is not sequestration, it is recycling. When the algae is burned,
whether in a power plant or in an organism, it will again release its CO2.
That delays the release of CO2, but we will end up with just as much CO2 in
the atmosphere eventually, UNLESS the amount of coal being mined and burned
is cut in half, and I don't think that is the intent of the R&D sponsors.

3. Parasitic loads for pumps and blowers, plus the capital and maintenance
costs of the algae farm, plus makeup water for the huge evaporative losses,
plus fertilizer for the algae, will further burden the economics and the
power output.

4. Algae converts CO2 to plant sugars and cellulose by photosynthesis.
Exposing all the algae to that much sunlight will require a very large land
area. Photosynthesis efficiency is about 12%. The plant efficiency would be
around 40%. Combined efficiency would be 4.8%. Solar PV efficiency is
nominally 16%. So converting the same land area to solar PV would produce
roughly three times as much electricity. New thin-film solar collectors now
being produced at prices competitive with coal-fired generation.

These 4 logic problems combine to show that the algae scheme will produce
less electricity, more CO2, and lower return on investment. Think outside
the box, but put the algae scheme back in the box and bury it.

Michael P. Gembol

 Letters from Readers<http://www.energycentral.com/centers/energybiz/ebi_detail.cfm?id=527>
Energy Central - Denver,CO,USA
*...* there's an intriguing possibility of producing a charcoal based
low-runoff "*terra preta*" fertilizer using pyrolization that captures
nitrogen from the *...*
 See all stories on this
topic<http://news.google.com/news?hl=en&ncl=http://www.energycentral.com/centers/energybiz/ebi_detail.cfm%3Fid%3D527>

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-- 
Michael the Archangel
"Politicians will never solve The Problem;
because they don't realise they are The Problem.".
-Robert ( Bob ) Parsons 1995
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