Lotus engine makes debut

The lightest and smallest automotive engine for series hybrid drivetrains was recently unveiled at the 63rd Frankfurt International Motor Show.

Automotive engineering consultancy Lotus Engineering developed the 'Range Extender' engine for Jaguar's new XJ plug-in hybrid model through the UK Technology Strategy Board-funded Limo-Green project.

With the Range Extender on board, the XJ has a range of 620 miles and a top speed of 110mph, said Matthew Reed, spokesman for Lotus Engineering.

He added that his company is now marketing the design to engine makers for incorporation into any vehicle.

'It weighs 56kg whereas similar engines can be 85kg,' he said. 'The package size is small so it can be integrated into a small city car or a SUV.'

Reed explained the weight reduction comes mostly from the engine's aluminium monoblock construction, which integrates the cylinder block, cylinder head and exhaust manifold in one casting. 'It reduces the parts count by 30 per cent and that brings a smaller package and reduced cost,' he added.

The three-cylinder 1.2 litre Range Extender engine uses an optimised two-valve port-fuel injection combustion system and can be operated on alcohol-based fuels or gasoline.

The engine is expected to produce low emissions and attain high fuel efficiency. Reed said the Range Extender is expected to emit only 120g/km CO₂ in emissions.

The engine will be first demonstrated before the end of November and Reed said Lotus Engineering hopes to have engines installed in vehicles in two years. 'This engine design uses well-understood technology and off-the-shelf parts,' he said. 'So it offers a fast route to market for start-up companies looking to enter the market with a series hybrid vehicle.'