UCS said there are ways to meet targets for the Renewable Fuel Standard without straining food supplies. Oil lobby American Petroleum Institute, often critical of the RFS, said EPA's proposed mandate for 14 million gallons of biofuel for 2013 depends on a "non-existent" commercial cellulosic biofuel sector. EPA's proposal, said API, "is unworkable."
UCS said the mandate for the production of 36 billion gallons of biofuels by 2022 may lead to "serious" environmental and economic consequences.
UCS Clean Vehicle Program scientist Jeremy Martin said renewable energy shouldn't compete with food supplies.
"We can't afford additional strains on our food supplies, especially when the drought is expected to continue through 2013," he said in a statement.
The green advocacy group says that renewable fuels based on non-food feedstocks could help cut conventional oil use in half during the next 20 years.
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