Westport Innovations has announced that it has developed a bus engine fuelled by a mixture of hydrogen and natural gas that looks set to win a number of new contracts.

The engine has already been bought by the SunLine Transit Agency in California in a project that will enable commercial fleets to begin using hydrogen in internal combustion engines

Westport's chief operating officer Michael Gallagher described such new blends of fuel gas as 'a unique near-term opportunity in commercial vehicle operations'.

'With this engine-fuel combination, there is the potential to enable our customers to cost-effectively introduce hydrogen into their fleet operation at the pace they choose'.

Tests have been carried out at Westport, using a blend of 20 per cent hydrogen and 80 per cent natural gas. They indicate a 'dramatic reduction' in oxides of nitrogen, and could pose effective and economical long-term competition to a number of other fuel sources.

With no adverse effects on the engine's original torque and fuel efficiency, engines run on the composite fuel are 80 per cent cleaner than the average transit bus and 60 per cent cleaner than the newest diesel engines.

Tommy Edwards, director of maintenance for SunLine, said the evidence shows that 'transit and other commercial vehicles running on hydrogen-natural gas blends are a clean, viable option for the transportation sector'.