Volvo will be testing three new range-extended electric concepts

Volvo has announced it is working on three types of range extended electric cars that offer the economy of pure electric motoring but also the ability to be driven more than 600 miles without stopping.

Range extenders add an internal combustion engine to a primary electric motor to generate electricity once the battery gets low, meaning owners can use them for long journeys without the need to stop the car and plug in for a recharge. In some set-ups, the petrol or diesel engine can also indirectly drive the wheels, supporting the electric motor.

Two of Volvo’s solutions are based on the C30 Electric prototype, while the third is based on the V60. Volvo is already planning to bring a plug-in electric car to market; the V60 diesel plug-in hybrid will go on sale in 2012.

“This is an exciting expansion of our increasing focus on electrification,” says Volvo’s Derek Crabb. “Battery cost and size mean that all-electric cars still have a relatively limited operating range. With the Range Extender, the electric car has its effective range increased by a thousand kilometres – yet with carbon dioxide emissions below or way below 50 g/km.”

Electric only driving range is lower in an ‘E-REV’ than a pure electric vehicle – generally only around 40 or 50 miles – but research shows 80% of European car journeys are less than 40 miles, meaning most of the time E-REV owners will be driving on power drawn from a mains electricity supply.

Volvo’s two C30 Electric-based concepts have had the large battery pack replaced with a smaller version to accommodate a petrol engine at the rear of the car. The first has a 60hp engine connected in series – that is to say, it never drives the wheels directly – to a 40 kW generator that, after 68 miles of pure electric motoring, cuts in to power the car’s 111 hp (82 kW) electric motor. The driver can also choose to let the generator charge the battery instead, which increase electric only range.

In the second C30 concept, the same 111 hp (82 kW) electric motor drives the front wheels for pure electric driving of up to 46 miles, then a turbocharged 190 horsepower engine fires up to charge the battery, increasing range. But the parallel configuration means the engine can also be connected directly to the rear wheels via a six-speed automatic transmission giving the car more than 300 hp. Accelerating to 62mph takes less than six seconds but the petrol/electric combo also means better fuel efficiency when cruising on the motorway.

The V60-based concept joins together the 111 hp (82 kW) electric motor and 190hp turbo petrol engine under the bonnet, along with a two-stage automatic transmission and a 40 kW generator. It’s a similar set-up to the Chevrolet Volt/ Vauxhall Ampera that sees the car powered solely by electricity up to 31 mph. The combustion engine is activated at higher speeds to drive the front wheels via the gearbox and recharges the battery pack whenever needed.

Testing of the three concepts will be in the first quarter of 2012.