Net Energy: More Harm than Good?

Abstract: Energy outputs from ethanol produced using corn, switchgrass, and wood biomass were each less than the respective fossil energy inputs. The same was true for producing biodiesel using soybeans and sunflower, however, the energy cost for producing soybean biodiesel was only slightly negative compared with ethanol production. Findings in terms of energy outputs compared with the energy inputs were:

• Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced.
  
• Ethanol production using switchgrass required 50% more fossil energy than the ethanol fuel produced.
  
• Ethanol production using wood biomass required 57% more fossil energy than the ethanol fuel produced.
  
• Biodiesel production using soybean required 27% more fossil energy than the biodiesel fuel produced (Note, the energy yield from soy oil per hectare is far lower than the ethanol yield from corn).
  
• Biodiesel production using sunflower required 118% more fossil energy than the biodiesel fuel produced.
  

• Thermodynamics of the Corn-Ethanol Biofuel Cycle (7/2006) (see abstract)
  
  “inefficient solar cells produce ~100 times more electricity than corn ethanol”
  
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• Ethanol from Corn: Just How Sustainable Is It?
  
• Ethanol from Corn: Clean Renewable Fuel for the Future, or Drain on our Resources and Pockets?
  

• Biofuel Skeptic Extraordinaire
  
  By Tom Philpott, 08 Dec 2006
  
  
  
  An interview with David Pimentel
  
  
  
  “No. I don’t care what kind of imagination you have, it won’t work.”
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  Ethanol fuel from corn faulted as ‘unsustainable subsidized food burning’ in analysis by Cornell scientist