Question: how long would you estamate for all fossile fules to burn out and also will we ever have cars with a moto no engen and when you go to the garage will you have to buy a battery insted of petol ? tb a.s.a.p

Jon Copley answered on 25 Jun 2010:

For oil, people have estimated it could run out in around 50 years. For natural gas, it’s around 100 years, and for coal, somewhere between 200 to 400 years. But how long fossil fuels will last depends on two things: how much fossil fuel there is in the world, and how quickly we use it.

People keep finding more fossil fuels, particularly under the seafloor in deeper water (such as where the oil leak is in the Gulf of Mexico – that’s at 1000 metres deep). It used to be impossible to extract the oil and gas in such deep water, but now there is the technology to do it (though as the Gulf of Mexico oil spill shows, the technology has its problems).

There are big reserves of fossil fuels under the seabed in the Arctic, which could keep fossil fuels going for much longer. Again, these used to be out-of-reach, but now there is the technology to extract them. And right now countries are arguing over who owns which bits of the Arctic Ocean because of the oil and gas there (and my own view is that the ocean doesn’t belong to anyone – instead, we all have a responsibility to look after it!).

But even though people are finding more fossil fuels, they will eventually run out, because they are a “non-renewable” energy source, unlike solar, wind or wave power.

So will we ever have cars that just have electric motors, and only need recharging at a garage, rather than filling with fuel? Yes – they already exist, but there aren’t many of them yet. Here’s one that I really like – the Tesla Roadster, which is an electric sports car that went on sale this year:

http://en.wikipedia.org/wiki/Tesla_Roadster

…and I like it because it shows that electric cars can be just as fast, and just as cool, as other cars. But at the moment the Tesla is very expensive (£86000) – and that’s one of the problems with electric cars right now (they cost much more than ordinary cars, so people keep buying ordinary cars).

The other problem is that not many garages have the equipment to recharge the batteries of electric cars yet. There are plans to change that – the Mayor of London wants 100000 recharging stations for electric cars around London by 2020, to make London “the electric car capital of Europe”. I hope that happens.