In a pilot program launched this spring, the Los Angeles International Airport and the City of Los Angeles Department of Public Works have begun collecting uneaten portions of air travelers' meals and converting them into fuel. Leftovers are pulverized, mixed with water, and heated to accelerate decomposition. Bacteria break down the food and liberate methane gas, which is piped to a power generation plant. Louise Riggen, recycling coordinator at LAX, says the airport currently dumps 8,000 tons of wasted food each year. Riggen hopes those scraps will end up powering Los Angeles instead. "If food waste could become a form of renewable energy, that would be beautiful," she says.