The whispering wheel

Use a small diesel engine to run a generator to power electrical motors in the wheels. The result a very low emission, very fuel efficient, very quiet bus.

This winter, in the city of Apeldoorn, a city bus will be used to prove that the claims about the new invention are true. These are quite bold. E-traction, the company that developed the bus, boasts fuel savings of up to 60 per cent, with emissions down to only a fraction of the soot and carbon dioxide an ordinary bus would blow out of its tailpipe.

In addition, the test bus requires no adaptation, its drivers need no extra training and there'll be no discomfort for passengers. It will simply run on diesel, just like all the other buses, and it should be just as reliable. One thing however will be very different; the Apeldoorn bus hardly makes a sound, hence its nickname "the whisperer".

By just putting a tire on it you can drive a bus, a car, anything with it. Since the wheel is in fact the engine, no axles or any other friction-producing and therefore energy-wasting mechanical parts are needed.

Even the transmission is unnecessary; if you want to go faster you just run more electricity through the engine. And it works really well while braking, when the in-wheel engine works as a generator, produces electricity to charge the batteries.

Link from Amy