However, despite claims from Budget Rent A Car's director of sales and marketing, Paul Johnson, that liquefied petroleum gas will supersede diesel completely for van fleets within the next five to 10 years major fleets were less bullish. Paul Bellamy, international facilities manager for DHL, said: 'We are committed to liquefied petroleum gas because of the environment and also because we have to keep our options open in town and cities in case local authorities say you must use alternative fuels to enter their towns and cities.' The Royal Mail is trialling 21 LPG and compressed natural gas mail vans in Croydon to assess their viability in improving the exhaust emissions of its 28,000 strong fleet. John Roberts, chief executive of the Post Office, said: 'With a fleet our size environmental considerations figure prominently. Royal Mail's participation in this and other trials demonstrates our intention to be in the forefront of efforts to reduce the environmental impact of road transport.'
And Humberside Police has already heralded the end of the diesel revolution, by converting its entire 460-strong fleet, many of them diesels, to run on LPG. Ironically, the same economic and environmental reasons which drove fleets to diesel in the early 1990s are today driving them to gas.