Almost all biofuels used today cause more greenhouse gas emissions than conventional fuels if the full emissions costs of producing these “green” fuels are taken into account, two studies being published Thursday have concluded.
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These studies for the first time take a detailed, comprehensive look at the emissions effects of the huge amount of natural land that is being converted to cropland globally to support biofuels development.
The destruction of natural ecosystems — whether rain forest in the tropics or grasslands in South America — not only releases greenhouse gases into the atmosphere when they are burned and plowed, but also deprives the planet of natural sponges to absorb carbon emissions. Cropland also absorbs far less carbon than the rain forests or even scrubland that it replaces.
Together the two studies offer sweeping conclusions: It does not matter if it is rain forest or scrubland that is cleared, the greenhouse gas contribution is significant. More important, they discovered that, taken globally, the production of almost all biofuels resulted, directly or indirectly, intentionally or not, in new lands being cleared, either for food or fuel.
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The clearance of grassland releases 93 times the amount of greenhouse gas that would be saved by the fuel made annually on that land, said Joseph Fargione, lead author of the second paper, and a scientist at the Nature Conservancy. “So for the next 93 years you’re making climate change worse, just at the time when we need to be bringing down carbon emissions.”
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International environmental groups, including the United Nations, responded cautiously to the studies, saying that biofuels could still be useful. “We don’t want a total public backlash that would prevent us from getting the potential benefits,” said Nicholas Nuttall, spokesman for the United National Energy Program, who said the United Nations had recently created a new panel to study the evidence.
“There was an unfortunate effort to dress up biofuels as the silver bullet of climate change,” he said. “We fully believe that if biofuels are to be part of the solution rather than part of the problem, there urgently needs to be better sustainability criterion.”
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Industry groups, like the Renewable Fuels Association, immediately attacked the new studies as “simplistic,” failing “to put the issue into context.”
“While it is important to analyze the climate change consequences of differing energy strategies, we must all remember where we are today, how world demand for liquid fuels is growing, and what the realistic alternatives are to meet those growing demands,” said Bob Dineen, the group’s director, in a statement following the Science reports’ release.
“Biofuels like ethanol are the only tool readily available that can begin to address the challenges of energy security and environmental protection,” he said.
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“This land use problem is not just a secondary effect — it was often just a footnote in prior papers,”. “It is major. The comparison with fossil fuels is going to be adverse for virtually all biofuels on cropland.”
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This is just common sense to me when you look at the energy output of Petroleum based fules vs. Biofuels. They are only about 80% as efficient so naturally more fuel has to be burned which means that more land has to be used for cultivation which means that trees have to go which means that carbon sink is lost. Simple. I admit I didn't know about the impact the grasslands could play but I can see that too.
Biofuels, Global warming
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