It is part of a move by Kent-based Apex Lifts to become more environmentally-friendly and save money.
It has a fleet of about 50 cars and vans and made its first move towards achieving new environmental management certification by ordering six new 1.6i LPG/petrol-powered Combo vans.
They will be used by maintenance engineers operating within London and so will be exempt from the capital's congestion charge.
Fleet manager Mick Holderness said: 'The Combos are part of that move to being greener. With the growing number of LPG sites the Combos have not proved to be a problem in terms of re-fuelling.
'The added benefit is the probable £8,000 per year savings to be made as our vans are used regularly within the London congestion charge zone.'