Almost half of drivers would consider buying an alternatively-fuelled car, according to an RAC survey.

As many as a quarter are likely to make a "green car" purchase in the next five years. the poll showed.

But the cost of environmentally-friendly vehicles was a problem for around 25%, while the small range of battery-powered electric vehicles was also a concern.

The poll, involving 1,400 motorists, also showed that 75% were unaware of the existence of the Government's plug-in car grant which is designed to help with the cost of buying new electric, plug-in hybrid electric and hydrogen fuel cell cars or vans.

Those surveyed felt that, of the various greener motoring options, the most popular was likely to be low-emission petrol or diesel-engined cars, followed by hybrid electric.

Only 10% reckoned that pure electric would prove the most popular, with just 8% plumping for hydrogen-powered vehicles.

RAC technical director David Bizley said: "Schemes such as the Government's plug-in car grant are great incentives to encourage consumers to consider greener vehicles but it is clear that awareness remains relatively low and opinions on alternatively-fuelled vehicles are still mixed.

"The car is an essential part of everyday life in Britain so it is vital that its future is safeguarded by adopting the new low-carbon alternatives as they become available and affordable. In order for this to happen, consumers' perceptions of low-carbon vehicles must be changed."

Local Transport Minister Norman Baker said: "The number of people who are signing up for our plug-in car grant continues to rise which is good news for the environment, the economy and consumers.

"The Coalition Government's ongoing investment in ultra-low emission vehicles is helping to transform the UK into a world leader in this industry, and I welcome the increasing awareness of the benefits of these vehicles."