Toyota will unveil the next generation Prius next year at the Detroit Auto Show. Sales will begin in late 2009. It will be larger than the current generation, but also greener and better to drive than today’s globally successful model.

The hatchback will be about 10cm longer and 3cm wider than today’s car and, to cope with the bigger size, the engine will move up from 1.5 to 1.8 litres. Power should increase to 100bhp.

Toyota says it can achieve this higher output while still improving economy and lowering emissions. Sources in Japan claim that Toyota is aiming for a 12 per cent improvement in fuel consumption, leading to a combined economy of over 70mpg and C02 emissions of just over 90g/km.

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