In a decision that environmentalists are praising and biofuel producers are fuming about, Massachusetts has announced that waste-based biofuels are the only ones guaranteed to meet the state's renewable fuel standards.  

The ruling could potentially leave algae-, switchgrass-, and corn-based producers high and dry, although it's not quite the ban that some news outlets have called it, says Massachusetts Department of Energy Resources spokesperson Lisa Capone.  

In accordance with the state's Clean Energy Biofuels Act of 2008, petroleum suppliers are required to make 2 or 3 percent of their sales by volume from qualifying biofuels beginning July 2011.  (The program officially begins July 2010, but the mandated volume will be waived in the first year.)

On Wednesday, the state said that waste-based biofuels qualified due to their likely 50 percent reduction in greenhouse gas emissions. For other fuels, however, the state would not be making a decision until the U.S. Environmental Protection Agency and California Air Resources Board agree on ways to analyze the greenhouse gas reductions from such fuels.  

"The department is awaiting those results before we begin qualifying other types of biofuels," Capone says. "Biofuels from waste feedstocks will likely meet that threshold without the analysis."  

That contentious analysis primarily relates to measuring the indirect greenhouse gas emissions caused by reducing domestic food production if agricultural fields are used instead to grow corn or switchgrass for biofuels. Experts say that other countries will take up the slack in the world's food supply, clearing forested land and therefore reducing the benefits of biofuels.

In July, Timothy Searchinger of Princeton University and 10 scientists and engineers, wrote in Science, that doing biofuels right means taking advantage of degraded lands, crop and forestry residues, and municipal and industrial wastes.  

"There's a gigantic number of scientific publications that say this is the policy that should be followed," Searchinger says.

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