Natural gas vehicles are taking off with several fleets. Clean Energy Fuels Corp. reported that its customers ordered 70% more natural gas-powered vehicles in the first nine months of 2013 from the same period last year. Looking back at 2013, the pronounced trend toward natural gas as a transportation fuel is clear, said Clean Energy CEO Andrew Littlefair. READ MOREThe Article Clean Energy Sees NGV Numbers Climb in 2013 appeared first on Automotive Digest.