Nobody seems to like brown grease, but if you heat it up enough, you’ve got something, says Medgar Evers College assistant chemistry professor Lawrence Pratt: an alternative source of fuel. “Someday petroleum will run out,” he says, and food waste heated to 350 celsius and above is a potential replacement. “We can’t continually rely only on fossil fuels.” Pratt and his compatriots at Medgar Evers College experiment with heated brown food grease. “This stuff does not come from coal, petroleum or natural gas,” says Pratt. “It comes from waste. We need energy from algae. We need solar, we need wind,” he says.