According to the Rubber Manufacturers Association, tire-derived fuel is the largest market for scrap tires in the United States. In 2009, more than 2 million tons of tires were turned into fuel.
The EPA maintains that tires are a quality fuel source because they produce the same amount of energy as oil and are actually 25% more efficient than coal. Emissions from tire-derived fuels are also lower than those from coal.
You won’t find tire-derived fuel at your local gas station, however – most of them power cement kilns and pulp and paper mills.