Lose-Lose on Biofuels?
The American Magazine features an update on misguided ethanol and biofuel mandates, from a recent EPA report:
While the Environmental Protection Agency (EPA) analysis suggests that the switch toward renewables will decrease ammonia, carbon monoxide, and benzene, it also predicts “significant increases in ethanol and acetaldehyde emissions” and “more modest increases in nitrogen oxides, formaldehyde, particulate matter, hydrocarbons, acrolein, and sulfur dioxide.” Citing time constraints, the EPA did not do a full analysis of the net health effects of these emission profiles, but a reasonable assumption is that the detrimental health impacts from increased particulate matter will at least offset the health improvements from the predicted reductions in the other pollutants.
Supporters of the Energy Independence and Security Act of 2007 (EISA) also claimed that it will reduce greenhouse gases. Both Speaker Pelosi and then-President Bush said the bill will help reverse global warming. Indeed, much of the early enthusiasm for biofuels was based on the belief that their use would reduce greenhouse gases. It is true that burning biofuels results in less tailpipe emissions of greenhouse gases relative to burning petroleum. Yet this ignores the increase in emissions that results from the production of biofuels, especially the land use changes as farmers convert forest and grassland into cropland for biofuel production. An article published in Sciencemagazinein 2008 found that “corn-based ethanol nearly doubles greenhouse gas emissions over 30 years and increases greenhouse gases for 167 years.” Another article in Scienceconcluded that crop-based biofuels create a “biofuel carbon debt of 17 to 420 times more carbon dioxide than the greenhouse gas reductions that these biofuels would provide by displacing fossil fuels.”
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