1.2-litre three-cylinder unit will be fitted to Jaguar XJ concept

Lotus has revealed a ground-breaking 1.2-litre range extender engine.

The unit, which is similar to that found in the Chevrolet Volt, produces 47bhp and will be fitted to a Jaguar XJ as part of a project to create an exectutive saloon with less than 120g/km emissions.

The 56kg three-cylinder petrol engine is attached to an electricity generator and powers both the car’s electric motor and charges a battery pack.

The engine is an all-new design from Lotus and features an aluminium monoblock construction integrating the cylinder block, cylinder head and exhaust manifold in one casting. This reduces weight, assembly costs and engine size, while improving emissions and durability.

Both alcohol-based fuels and petrol can be used. The unit has been designed by Lotus Engineering, the company’s consultancy-division, and will be sold to other manufacturers.

However, a spokesman for the car maker said it was a “possibility” it could appear in a Lotus.

“A lot of Lotus Engineering technology is for other manufacturers but Lotus looks at the best technology with regards to using it in its cars," he said.

Initially the Lotus range extender has been developed for a Jaguar, as part of the “Limo-Green” project funded by Lotus Engineering, Jaguar, MIRA and Caparo.

Jaguar told Autocar this technology could find its way into its road cars.

“This is the sort of technology we are looking towards,” said a spokesman.

An XJ mule will be ready by the end of the year to test the new Lotus range extender. The range extender will be on display at the Frankfurt motor show next week.

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