General Motors has confirmed it plans to start dynamic testing of the Chevrolet Volt later this month, before the new electric car goes into production in 2010. According to the Volt’s project leader Frank Weber, the car has become GM’s number one engineering project and is undergoing a hugely accelerated development programme in a bid to make it the world’s first mass-produced, plug-in electric car, with a price tag of around £20,000. Weber revealed to Autocar that his team are currently trying to meet several key objectives, including a 40-mile battery-only range and a 10-year/150,000-mile life from the lithium-ion battery. The car should also have a 100mph top speed and entertaining road manners. Unlike hybrids such as the Toyota Prius, the Volt does not use a petrol engine for propulsion. It is powered by an electric motor, which uses a petrol or diesel powerplant as a back-up, recharging the battery while the car is on the move.GM sources say the engineering focus at the moment is concentrated solely on launching the car with an engine that can run on either E85 ethanol or conventional petrol. The Volt has been designed primarily for the American market, but diesel versions aimed at Europe will follow several years later. The car has also been designed to be capable of accommodating a hydrogen fuel cell as its power source. GM has reaffirmed its pledge that the Volt will be the world’s first mass-produced plug-in electric car when it goes on sale in 2010. The company’s designers have also confirmed that plenty of styling cues from the 2007 concept car will be carried over to the final production version. “We want to make a fashion statement as well,” chief designer Bob Boniface told Autocar. “The Volt needs to stand out and be a little different from anything else we do.”Boniface also revealed that the final production version would retain plenty of cues from the concept car, crucially the coupé-like hatchback rear end, as well as front and rear styling elements. However, the car’s design has been adapted from that of the concept, for practical reasons. The production version will be a five-door five-seater built on the next-generation Delta platform, like the next Astra. The need to increase aerodynamic efficiency has also influenced the styling and engineers are targeting a best-in-class drag co-efficient, understood to much less than .30. Design sources have also revealed that other Volt body styles are planned. GM has not ruled out bringing a sportier-looking coupé variant to market that would look far closer to the original concept, and possibly an estate version.