Coachella Valley, Calif.-based SunLine Transit Agency launched the first ever hybrid fuel cell bus to be put into revenue service in California last week. The ThunderPower LLC bus, a joint venture between Thor Industries and ISE Research, uses a fuel cell instead of an engine. The fuel cell runs on hydrogen from renewable sources (such as wind or solar power) and air to produce electricity to power the 30-foot bus. The electricity produced by the fuel cell is routed to electric motors that turn the wheels through the differential. The bus achieves 7 to 11 miles per gallon, double the mileage of convential buses. A regenerative braking technology increases operating efficiency 20% to 30% by using motors to generate electricity during the braking process. The electricity is then stored in battery packs until acceleration is necessary. Other key funding and technology partners in the project include the U.S. Department of Transportation, Sacramento Municipal Utility District, CalStart, South Coast Air Quality Mangement District, El Dorado National, UTC Fuel Cells, Siemens, Quantum Technologies and SunLine Transit Agency.