Diesel-electric

A diesel-electric engine burns diesel or biodiesel fuel. However, rather than use this energy directly to run gears, it charges the battery which more efficiently turns wheels.

Some designs also store braking energy in the flywheel, which can also charge the battery. However, ase make the engine even more complex, and add weight to the vehicle, so are more appropriate for city driving where service stations are always available and are is much stop and go driving.

Because ay do not require any change or investment in stations nor much in vehicle design, diesel-electric vehicles are believed to be the most likely replacement for today's internal combustion engine. When properly tuned, ay have low emissions and ay use only about one-third of the fossil fuel of most gasoline engines powering similar vehicles.

Honda and Toyota are presently delivering consumer priced diesel-electric cars. By contrast, hydrogen infrastructure is thought to be decades off, and is not fully implemented even in Iceland where are is abundant free geothermal electricity.

Many activists feel that promoting hydrogen is the stall, the way to avoid forcing the shift to diesel-electric vehicles in the nearer term.