Back in January the Volt was easily the surprise of this year’s Detroit motor show. Chevrolet reckoned its radical electric four-seater was such a breakthrough that it would transform the way we drive when it arrived in showrooms by the end of the decade.
And it’s just announced that the production model will be significantly more efficient at scything through the air: the Volt has been sent to GM’s wind tunnel where Chevrolet’s aerodynamicists has smoothed off some of its blunt surfaces to create a shape that is 30 percent more effective at cutting cleanly through the air at speed than the original concept. That’s a massive saving when you consider air drag account for one in every five gallons of fuel a car burns. But that's compared to a concept car so we wait to see what the production car's drag coefficient will be.
Remind me about the Volt’s technology…
Here’s how it works. Plug the Volt into your mains for three hours and its small and powerful 250v electric engine will give you a range of 40 miles, which according to GM is enough for three quarters of most commutes into work. If you need to go further, a 1.0-litre three-pot combustion engine cuts in when the battery dies. But the engine doesn't drive the wheels - it acts as a generator and charges the battery, allowing the engine to be located anywhere in the car and doing away with the need for a bulky and heavy gearbox.
The result is an exceptionally roomy car – the fuel tank, batteries and engine can be placed anywhere in the car for optimised packaging – that can drive from Land’s End to Edinburgh without having to stop for a refuel. With a full charge and a full tank, you'll be able to cover 640 miles. If you drive 60 miles between charges you'll get 150mpg, as the petrol engine will only cut in for the last third of your trip. Driving the Volt for a year would save 4.4 tonnes of CO2 and 418 gallons of unleaded compared to a traditional petrol car.
But will it take three months to cover that kind of distance?
No – the Volt will have the performance to match its sleek looks. With a combined output of 190bhp and a mighty 236lb ft of torque, the lightweight Chevy will hit 60mph in 8.0 seconds and top out at 120mph. And the combustion engine can be developed to run on diesel, unleaded or even hydrogen. Our sources say the Volt will borrow the front-drive architecture from the next Astra to save costs and slash development time.
One of the stumbling blocks GM is facing is developing the high-tech lithium-ion batteries for the Volt. Because they absorb and deploy their charge so quickly, they get hot and they need plenty of chemical stability. They also need to be light, inexpensive and durable. But using the same technology as the batteries in your mobile phone GM reckons it’ll crack the problem – and soon.
And what does Bob Lutz, GM's car czar, think?
Lutz is actually one of the most important men in the American automotive market, and the driving force behind the Volt. 'This is the most exciting programme I have had anything to do with in my career,' he said when he unveiled the concept at Detroit in 2007. 'Everything else has been a variation on a theme but this is ground-breakingly different. It will make a profound difference not just to the automotive industry but to the way we live.' Powerful words from a man who has been at the centre of the motoring world for half a century. When he talks, the world cocks an ear...