Hybrid cars are becoming more popular and more diverse, with new ranges coming out all the time. In 2009, companies such as Toyota, Mercedes, Lexus and Porsche are all due to be releasing new hybrid car ranges, to great acclaim from environmentalists.

But why are environmentalists, scientists and the general public so keen on the idea of switching from traditional petrol cars to hybrid cars? Because of the effect that CO2 emissions are having on the environment, and the hybrids ability to cut down those emissions considerably, the hybrid car is being championed as a tool in the fight to reduce the damage we are doing to the planet.

CO2 emissions are largely responsible for global warming, a very real danger to the planets ecological system. With such dangers as arctic ice raising the water level of the oceans, increased temperatures killing off plants and animals and air quality being severely impaired it is important that we start developing ways of reducing our CO2 output.

This is where hybrid car technology comes in. Car travel is a major source of CO2 emissions. In the UK, transport (not including air travel) is responsible for 24% of the UK's domestic CO2 emissions, with car travel taking up 90% of that figure.

So any method of reducing such emissions would go a long way to helping reduce the damage that we are doing to the environment. That is where hybrid car technology steps in. With its ability to switch between electric and conventional car systems the emissions from a hybrid car are far less than that of a 'traditional' car.

If the use of hybrid technology in cars were to become widespread then the figures on CO2 emissions would drop by a significant number, helping the UK to reduce its impact upon global warming.

For the public who might not be that concerned about CO2 emissions, there is one more practical benefit. Namely, a hybrid uses less petrol, saving on the person's weekly fuel expenditure.

So why not just get an electric car, then? Wouldn't that save as much or even more petrol? Sure, but there's a security issue. Many electric car owners have told horror stories of being out on an abandoned road, far from home, only to have the battery run out of power. It doesn't matter how far the closest gas station is at this point.

Hybrid owners, however, overcome this annoyance. The engine on a hybrid starts up as soon as it detects that the battery is getting low. As it runs, this motor charges the battery. As a result, a hybrid vehicle never requires being plugged into an electrical outlet. The engine does it all. Just don't forget to fill the petrol tank.