LPG autogas is the answer to reducing motor carbon emissions, according to Mike Chapman, autogas manager for the LP Gas Association. He said that while the debate continues about the carbon benefits of biofuels, it is a known fact that LPG reduces emissions from petrol vehicles by 20%. In addition vehicles using LPG enjoy major air quality benefits when compared with their diesel counterparts.

"LPG autogas is now well- established with strengthened government support in the last Budget guaranteeing the fuel duty for three years. This means that the price of LPG at the pumps will continue to be around half the price of petrol and diesel for the foreseeable future."

Current fuel duty on LPG is 6.105ppl compared with 48.35ppl on petrol and diesel. Between now and 2010 the duty on LPG will rise by 6.305ppl to 12.41ppl while that on petrol and diesel will rise 5.84p to 54.19ppl.

Chapman added that there are more than 20 million petrol vehicles on our roads and he reckoned converting to LPG offers the cheapest and quickest way to make a significant reduction in carbon emissions. "A real difference to the environment can be made now. With a national network of more than 200 LPG autogas-approved installers and with the price of LPG at the pumps being so low, many motorists will even cover the cost of the conversion in their normal motoring," he said.

Conversion of a modern car engine costs around £1,600. LPG autogas is currently available at over 1,300 outlets.