It may not be the most practical of designs, but a German duo recently succeeded in crossing much of Australia in a wind-powered car. They set records for longest distance traveled in such a vehicle, as well as a 36-hour distance record and others.
Dirk Gion and Stefan Simmerer both developed and piloted the Wind Explorer, which traveled from Albany to Sydney in 18 days. The car, which weighs only 200 kilograms, has small lithium-ion batteries that are charged overnight by a turbine erected on a bamboo tower. It also can be pulled along by a kite, when the wind blows in the right direction.
To be clear, the trip was not completely powered by wind: they did need to recharge the batteries directly from the power grid very briefly, meaning that they traveled across Australia for about $15 in fuel costs. When charged, the 8 kWh battery pack could bring the car about 400 kilometers before needing to be recharged.
This isn't the first attempt at a wind-powered car, of course. Others have used a more direct approach (though the kite aspect of this new vehicle is quite direct), with sails or other devices. One car even managed to use a turbine to move it faster downwind than the speed of the wind itself.
Wind power isn't likely to be a primary feature of new generations of clean-running cars, but it shows that there is no shortage of new places to look for new transportation ideas.