Two studies released February 7, 2008 (by the University of Minnesota and the Nature Conservancy; and Princeton University) determined that almost all biofuels produced today (particularly corn-based ethanol) produced more CO2 emissions than conventional petroleum when all production factors, especially land-use changes, are taken into account. Even though biofuels emit 50 to 95% less CO2 than conventional petroleum.
Holy rain forest destruction, batman!
Basically, many acres of farmland are being converted to products like corn for ethanol instead of for food and the slack has to be picked up somewhere. The studies suggested that the slack is picked up in places like South America and Asia where rain forest, peatland, and grasslands are being converted to crops.
Here's the kicker - the carbon, which is stored in the original plants and soil, is released as carbon dioxide. So much so that the carbon reduction benefit of the CO2 reduction can take hundreds of years to offset!!!
This "carbon debt" must be paid before the biofuels produced on the land can begin to lower greenhouse gas levels and have a positive effect on global warming.
The analysis calculated that a U.S. cornfield devoted to producing ethanol would have to be farmed for 167 years before it would begin to achieve a net reduction in emissions.
The conversion of peatlands for palm oil plantations in Indonesia ran up the greatest carbon debt, one that would require 423 years to pay off.
Researchers did note that some biofuels do not contribute to global warming because they do not require the conversion of native habitat. These include waste from agriculture and forest lands and native grasses and woody biomass grown on marginal lands unsuitable for crop production.
Some European countries (and Canada) are trying to fashion laws that restrict biofuel imports to those that were grown in an environmentally friendly manner. We'll be talking about the pros and cons of these laws later.
(classic Bacsik)
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