The Clean Air Vehicle Association is based in Atlanta, one of 20 U.S. cities currently violating the maximum limits of ground-level ozone concentration. The appeal for automakers and suppliers of fuels such as natural gas and propane is based on the here and now. All are currently available in large quantities and work with existing automotive technology with only minor modifications. The selling points for the public are that clean fuels are cheaper than gasoline, vehicle maintenance costs are lower, and there is no appreciable reduction in driving performance. A major drawback for the motoring public is availability at the retail level.
Safety is also a concern.
Alcohol fuels are more toxic and corrosive than gasoline, but the other alternatives may actually be safer than gasoline. Steel tanks for natural gas and propane must meet certain structural criteria, and in fact can enhance the structural integrity of a vehicle. Propane is the most widely used altemative fuel in the U.S., powering about 350,000 vehicles. And although natural gas is a distant second with 30,000, it is well positioned to become the primary alternative fuel of the future. But the race is not quite over.