Sustainable Triad is a great resource about environmental concerns and sustainability from my local area (the North Carolina Piedmont Triad). He just posted a story the other day about biofuels, one of the alternative energies I really like, and it's not a happy story.For ethanol production, if corn, switch grass, or wood is used as the source, the amount of fossil fuel consumed in production is greater than the equivalent ethanol output by 29% to 57%, depending on the source (corn is best, wood is worst).
For biodiesel production, if soybean or sunflower plants are used as the source, the amount of fossil fuel consumed in production is greater than the equivalent biodiesel output by 27% (soybeans) to 118% (sunflowers).
Note this important point: The claim is not simply that the energy input is greater than the energy output. Rather, the claim is that the fossil fuel input is greater than the useful (ethanol, biodiesel) energy output. Well, that's not good. The whole point of the substitution of ethanol or biodiesel for gasoline is to consume less fossil fuel, not more. This is bad news. If it takes this much fossil fuel to produce biofuels, with a 27% difference between petroleum input and biofuel output, what will we do when the petroleum is gone? Biofuels would be useless then. Peter, the blogger, said to do a Google search for "ethanol Cornell University," which I did, and found the story. The study found that:
- corn requires 29 percent more fossil energy than the fuel produced;
- switch grass requires 45 percent more fossil energy than the fuel produced; and
- wood biomass requires 57 percent more fossil energy than the fuel produced.
- soybean plants requires 27 percent more fossil energy than the fuel produced, and
- sunflower plants requires 118 percent more fossil energy than the fuel produced.
There is some good news for biofuels, thank goodness.Although Pimentel advocates the use of burning biomass to produce thermal energy (to heat homes, for example), he deplores the use of biomass for liquid fuel. "The government spends more than $3 billion a year to subsidize ethanol production when it does not provide a net energy balance or gain, is not a renewable energy source or an economical fuel. Further, its production and use contribute to air, water and soil pollution and global warming," Pimentel says. He points out that the vast majority of the subsidies do not go to farmers but to large ethanol-producing corporations. At least there's that.
So, what does this tell us about alternative energies? Still, so far, there's nothing that's going to let us break away from cheap oil. There's simply, so far, no alternative energy resource or combination of alternative resources that is going to give us a sustainable future under heavy energy use. I think that once the oil is gone, so will our ideas of how we interact with the world using external energy sources. We may, for better or worse (and I think better in the end), have to start living sustainably and delicately once again. Let's just hope that our past mistakes won't keep that from being possible.
UPDATE, 7/27/05 - This study appears to be bunk, as noted here and here. It's starting to get alot of press attention now, and that's bad, because it could be detrimental to biofuels taking over the energy market in the future. I'm going to try and do everything I can to point out the inconsistencies and bad assumptions in this study.
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