The forecast includes vehicles with factory-fit systems, such as those offered by Vauxhall and Ford, and market conversions from a number of independent operators, bringing the total number of dual and bi-fuel liquefied petroleum gas and compressed natural gas cars and vans on British roads to more than 60,000.
Vauxhall, the market leader in LPG bi-fuel vehicles, has sold 1,800 to date this year and expects to secure 3,000 registrations by the year end. A spokesman for the manufacturer said: 'LPG is something which needs a good infrastructure before people will buy into it. The market's changing all the time but while there are just 200 or so main public sites in the UK we believe sales will remain slow.'
The Society of Motor Manufacturers and Traders does not publish bi-fuel registration figures, but Barry Luff, sales director for LPG Systems, believes the 2000 estimate of 16,000 is accurate and further dramatic growth is on the cards.
'The 40,000 figure may prove to be slightly ambitious, but we've seen all the signs of a massive increase in interest from fleets,' he said. 'The refuelling infrastructure is becoming less of a problem for operators now that there are 500 sites up and running and others are being installed at the rate of one a day across the country. But the prospect of significant savings in fuel costs is what's really driving this forward.'
The current price of LPG is about 40p per litre, compared with 80ppl for petrol or diesel.