Plants grow better if there is lots of CO2 around, but devices to make the CO2 burn fuel or gas (link). Only a small fraction of the generated CO2 is actually used. The grower still gains because fuel is so cheap and subsidized anyway, but don't we generate enough CO2 already?

The suggestion is to take CO2 directly from the air using solar power and concentrate it in the green house. That way the system actually removes CO2 from the air overall. CO2 is taken out of the air by freezing it at night with an absorber refrigerator (link). The refrigerator is recharged with solar energy during the day while the frozen CO2 evaporates and feeds the plants.

Why not use Silicon solar panels and an electric freezer? Could work too, but an absorber refrigerator with a natural day-night cycle fits the application perfectly. Let's leave the Silicon to people who need power during the day.
-- kbecker, Sep 11 2003

Bad CO2 generator http://www.johnsong...dustrial/CO2Gen.asp
[kbecker, Oct 05 2004, last modified Oct 17 2004]

Good absorber refrigerator http://www.polarpow...ble-vaccine-ref.htm
See section "Characteristics of Absorption Refrigeration", heat comes from the sun. [kbecker, Oct 05 2004, last modified Oct 17 2004]

plants like to breathe.. http://www.saburchi...pters/chap0025.html
[po, Oct 05 2004, last modified Oct 17 2004]

CO2 growth data 1 http://www.co2scien...les/description.htm
[kbecker, Oct 05 2004, last modified Oct 17 2004]

CO2 growth data 2 http://www.asi.org/...2-plant-growth.html
[kbecker, Oct 05 2004, last modified Oct 17 2004]

"when are you gonna come down? When are you going to land? I should have stayed on the farm. I should have listened to my old man."
I suspect it's actually carbon monoxide that is the major waste product of power production though. I tried dwarf fruit trees and in my failure I suspect that they need massive amounts of water as well as too much "baby talk" (CO2) to be plausible for the average working man.
-- Zimmy, Sep 12 2003


How Green was my Galley
-- thumbwax, Sep 12 2003


plants like to breathe as well you know.
-- po, Sep 12 2003


[Zimmy] Carbon-monoxide is bad for you because it is very reactive. That same property makes it fairly harmless for the environment. In a mix of air 95% air with 5% CO the CO has a half life of about 5 hours (turns into CO2), so it is gone pretty fast from the environment.

[po] I like to breathe too, but a little extra food is nice. We are not talking about 100% CO2 here, but 1% at most. You can get 20% higher yield with less water and no extra fertilizer (links). Some sources report 70% for selected grains.
-- kbecker, Sep 12 2003


CO2 is pretty scarce in the atmosphere, on account of those dang wild plants using it up. This is half-baked because it is a sort of Rube Goldberg way of getting at the stuff.

Why not just free up the CO2 from limestone? There is lots of limestone. Acids are cheap. Plus this would have no moving parts.
-- bungston, Sep 12 2003


Because then you'd be releasing CO2 to the atmosphere, increasing the greenhouse effect. [kbecker] is recycling the CO2, rather than pulling it out from the earth (which is the problem with fossil fuels). It's easy to pull carbon out from underground, hard to put it back.
-- Worldgineer, Sep 12 2003


We shouldnt't want to put it back. That atmospheric carbon eventually turns into plants which feeds animals. The carbon is doing no good, really, being in the ground... The greenhouse effect is not really a "bad" thing. It creates more lush plant growth over the whole planet, which will in turn create more oxygen. Eventually the atmosphere will balance out again. And there will be lots of happy little trees, and happy little squirrels. And let me tell you, there is nothing more delicious than squirrel grilled with onions and peppers... <drool>
-- DeathNinja, Sep 12 2003


Suprisingly, [DN], your little world must be a very pleasant one. In my world they are cutting down all of the forrests, allowing for less conversion to oxygen and happy little grilled squirrels.
-- Worldgineer, Sep 12 2003


Ahh. I missed that distinction. But now I understand. Perhaps [kbecker] could put the hydroponic farm in a giant blimp shaped like a basking shark with a gaping mouth. CO2 would come in the open mouth and be filtered out like nutrious krill, increasing the relative CO2 for the garden within. The sharkblimp design would ensure a constant flow of air from which to harvest to CO2.
-- bungston, Sep 12 2003


[World] All the more reason to want lush plant growth.
-- DeathNinja, Sep 12 2003


[bungston], I think we have to bake this. A blimp with a hydroponic garden that absorbs CO2. It would fly around chimneys of coal firing plants to filter the air. Another fleet would cruise along busy interstates adn autobahns.
The project is finaced with fines from companies/countries that violate the Kyoto agreement.
-- kbecker, Sep 12 2003


Aren't they trying something like that on highways in Japan?
-- 2 fries shy of a happy meal, Sep 12 2003


Giant shark blimps? I hope so.
-- bungston, Sep 13 2003


Let's pipe power plant exhaust directly into a greenhouse and make an arseload of money on the crops. Now, if we could only carry around little herb gardens in our cars to do the same thing...
-- kevinthenerd, Sep 15 2009


wonder if growing plants under high pressure would do anything.
-- FlyingToaster, Sep 15 2009


Using something like a centrifugal a/c unit might be better, separating the CO2 by weight.

IMHO, the best way of providing CO2 (and Nitrates) for plants is to have a fish pond in the greenhouse.
-- marklar, Mar 10 2010



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