Remember the days when hybrid cars and hydrogen fuel cells seemed like little more than a mythical vision of the space age? Now they’ve come to fruition perhaps we should not be so quick to mock the latest inventions – even if the concept of a ‘flying green car’ will raise one or two eyebrows.

At the annual Electric Aircraft Symposium in San Francisco, the latest requirement for the invention of personal aircraft vehicles (PAVs) is that they adopt a green outlook. The annual PAV challenge has been re-branded as the General Aviation Technology Challenge with a green prize to be awarded from this year onwards.

PAVs are the latest step in the flying car concept. Instead of appearing as hover-capable wingless super machines, the likes of which you’d expect to see on an episode of the Jetsons, they instead take the form of advanced light aeroplanes. They can take off after a short run and are quiet enough so that they don’t upset your neighbours.

The idea behind the PAVs is that they will be able to fold their wings and drive on roads like an ordinary car, while also being able to zip through air space for speedy trips to the office or supermarket.

However, with fears growing about the fuel emissions of most aircrafts its encouraging to see that there is an environmental focus being placed on the development of even the most far-fetched concepts. At the moment the most realistic version of the flying car is the Terrafugia Transition, which currently clocks a mere 25 miles per gallon, though it can use unleaded fuel, unlike many light aircraft.

Clearly there’s some way to go before this latest green concept gets off the ground.