The concept showed that new features are paving the way for a 250bhp, 2.6-litre petrol engine to return average economy of more than 43mpg.
'This is a responsible large car with the fuel economy of a small model. We're setting out to challenge traditional values,' said design chief Peter Horbury.
Volvo claims to have achieved higher efficiency with advanced turbo technology and a higher compression ratio, but the VCC is also fitted with a stop-start system to save fuel when the car is stationary and automated shift manual transmission. An electric drive unit powered by an independent 42-volt battery is also used to improve engine throttle response at low revs.