Hydrogen cars

The trouble with today's cars is that they still put out a lot of pollution, and use up fossil fuels. One day, we have to run out of fossil fuels.The first way is that you can burn hydrogen in a modified car engine. Two companies, BMW GM and Mazda, are working on this. The engine works fine, but with about 20% less power - which is pretty reasonable, considering that we have been working on the petrol engine for a century or so. When you burn hydrogen in an engine, you get mostly water coming out of the tailpipe. You also get small amounts of oxides of nitrogen (from the nitrogen in the air), and even smaller amount of hydrocarbons (from traces of the lubricants in the combustion chambers of the engine). Even so, a hydrogen-powered car is much less polluting than a petrol-powered car.