Incorporated in 2001, Clean Energy is one of the largest vehicular natural gas providers in North America. It serves the transportation industry, as well as clients in the refuse, transit, shuttle, taxi and regional trucking sectors. The company also serves customers in the airport and municipal fleet markets. It designs, operates, maintains and supports natural gas fueling stations for compressed natural gas (CNG). Clean Energy serves Los Angeles International Airport, Phoenix Sky Harbor International Airport, SuperShuttle, Foothill Transit, Waste Management, SYSCO Foods, Denver International Airport, Denver RTD, MTDB of San Diego and the US Navy. The company, formerly known as Pickens Fuel Corporation, also offers assistance services for clean-air transportation.