Saturday, May 10, 2008

Things that Seem Obvious - Biofuels

Back to more stuff that seems obvious...

Biofuels are a good idea, primarily for two reasons. 1) We can grow more of them a heck of a lot quicker than we can grow more oil, which also then gives us better control of prices. 2) The CO2 they release into the atmosphere is CO2 they took out of the atmosphere only a short while before.

However, growing biofuels on land previously used for agriculture is a less good idea because 3) the conventional ways of making biofuels (grow complex plant, harvest it, crush bits of it, maybe ferment them for a while and purify) is pretty inefficient, it would force the price of food up and it would take an awful lot of land to grow enough fuel to make a significant difference. So I'm not sure why sugar-based biofuels, for example, are being touted at all.

What seems much more sensible is something along the lines of GM algae (small organisms, photosynthetic), which either produce the fuel directly, or which do the first stage of an integrated, single-site process. Algae make sugar, yeast change sugar into alcohol, distillation of the alcohol by energy produced on-site.

And the obvious places for this are on land we are not currently using - i.e. deserts or ocean.

Hydrogen fuel cells are nifty, but they just store energy, so shift the producing problem elsewhere.

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