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.

4 comments:

Ginger said...

I'm not sure I agree that biofuels are a good idea. Yes, your suggestion of GM algae would circumvent some of the problems about competing use of land, and the risk of food shortages. But one of my major objections to the use of biofuels is they give us permission to carry on regardless with our current ways of doing things.

At some point, we do need to re-evaluate and reduce our overall consumption. If biofuels enable urban drivers to carry on using unecessary SUVs, and people taking far more flights than they need to, then they are of questionable merit. Greater incentives to reduce energy use are needed, but biofuels are where investment and publicity are heading, because they represent a simple 'solution' that requires no idealogical change. Long term, I'm not optimistic about them.

Otepoti said...

Isn't the US's commitment to ethanol forcing up the price of food for the third world already? Or am I misinformed?

Ginger said...

Also, what would be the effect on ocean ecosystems if you suddenly introduced vast quantities of algae?

Anonymous said...

On a critical mass ride recently, some people from scarborough climate change campaign (the ones in very loud clothing at http://tinyurl.com/5tpc7q ) gave me literatre about how biofuels cause climate change, and we should protest to Gordon Brown against them. It doesn't really help the perception that a lot of eco campaigners are just anti-progress primitivist hippies. Oh well.