Biofuel Skeptic Extraordinaire: An interview with David Pimentel

Any worthy idea can withstand and even be improved by naysayers; scolds and skeptics play the useful role of pointing out obvious flaws. The biofuels industry has no more persistent, articulate, and scathing critic than David Pimentel, professor emeritus of entomology at Cornell University.

Grist recently spoke to Pimentel about why he thinks biofuels are an environmental dead end. Enthusiasts for crop-based energy would do well to at least examine his analysis.
Q: You claim corn ethanol’s energy balance is negative, and there’s a growing consensus that it’s positive. Why the difference?

A: Pro-ethanol people make it out to be positive by omitting many of the inputs that go into corn production. For example, they omit the farm labor — I’m not talking about the farm family, I’m talking about the farm labor. They omit the farm machinery. They omit the energy to produce the hybrid corn. They omit the irrigation. I could go on and on. Anyway, if I did all of those manipulations, I could achieve also a positive return.

However, that’s not the way these assessments are made. You can go check the noted agricultural economists who have looked at corn as well as other crops, and they do include the labor, they include the farm machinery, they include repair of the farm machinery, and so forth and so on. And so, those are all inputs that the ag economists include. Why are the pro-ethanol people leaving them out?