Almost all biofuels used today cause more greenhouse gas emissions than conventional fuels if the pollution caused by producing these "green" fuels is taken into account, two studies published Thursday have concluded.
....These studies for the first time take a comprehensive look at the emissions effects of the huge amount of 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 - increases the release of greenhouse gases into the atmosphere because the ecosystems are the planet's natural sponge for carbon emissions.
"When you take this into account, most of the biofuel that people are using or planning to use would probably increase greenhouse gasses substantially," said Timothy Searchinger, the lead author of one of the studies and a researcher on the environment and economics at Princeton University. "Previously, there's been an accounting error: Land use change has been left out of prior analysis."
Plant-based fuels were originally billed as better than fossil fuels because the carbon released when they are burned is balanced by the carbon absorbed when the plants grow. But even that equation proved overly simplistic because the process of turning plants into fuel causes it own emissions - through refining and transport, for example.