Bio-Fuels: Net Energy or Not?

A furor seems to be erupting over the latest from David Pimentel (of Cornell) - the article, with co-author Tad Patzek of Berkeley is in the most recent issue of the journal "Natural Resources Research". 

According to the Cornell press release (I haven't been able to read the actual article yet), Pimentel and Patzek find conversion of various plant products to ethanol or biodiesel to require MORE fossil fuel than the resulting bio-fuels displace, at least under North American conditions.

From their numbers, for ethanol production:

• Corn requires 29% more fossil energy than the fuel produced;
• Switch grass requires 45% more fossil energy than the fuel produced;
• Wood biomass requires 57% more fossil energy than the fuel produced.

For biodiesel:

• Soybean plants requires 27% more fossil energy than the fuel produced;
• Sunflower plants requires 118% more fossil energy than the fuel produced.

Green Car Congress and WorldChanging have lively blog commentary - there may at least be some bias from Patzek's sources of funding - but nobody seems to have numbers that completely disprove what they're talking about. Pimentel is quoted in the Cornell press release as pushing for investment in solar and wind, and producing electricity from burning biomass, which seems a pretty sensible plan.

Created: 2005-07-07 03:02:25 by Arthur Smith