With its revolutionary ‘range-extender’ engine, the forthcoming Chevy Volt stands head and shoulders above the other EVs and hybrids. Saeed Akhtar explains why
For all that the electric cars have to
offer, the general public tends to be wary of them. Regretfully, the detractors of electric cars are not to blame, for, in their present guise, these cars pose more problems than providing solutions for a better world. However, GM have trodden a different path. After more than three years of planning and obsessive research, the company’s first plug-in electric car is ready to go on sale this month as a 2011 model. Naturally, a lot of expectations are riding on this car. 
GM have packed enough cutting-edge technology under the Volt’s hood to make the car a serious contender for the most advanced electric vehicle in the world. Foremost among these is a bank of batteries hidden innocuously under the body. Developed by GM in conjunction with Compact Power Incorporated (CPI) of Detroit, these 220-cell lithium-ion packs weigh 170 kg each and store a maximum charge of 16 kW/h. But, in reality, GM have incorporated a software that limits the maximum usable power to 8.8 kW/h in order to extend the battery life to an astonishing 10 years. The Volt is also liquid-cooled and heated, unlike any other electric car or hybrid that relies on air to do the same.
At full charge, the Li-ion pack powers the Volt for the first 64 kilometres – a distance significantly longer than the average American’s daily commute – after which a small 1.4 litre petrol-powered four-cylinder ‘range-extender’ engine kicks in. Most of the power from this 75 PS engine is sent to the electric motor for locomotion, while the rest is used for charging the batteries. How much of power should go to which work is decided by the ECU, depending on the state of the battery charge and the power demanded by the driver at the moment. Thus, the Volt is not exclusively an all-electric car, but the first of a new breed of hybrids with an internal combustion range-extender engine.
Combining the two energy sources, the Volt delivers a staggering range of 500 km (in theory). According to its makers, a full charge will take approximately eight hours from a standard North American 120V, 15 A home outlet and less than three hours if one is using a standard 240 VAC outlet.
GM recently invited a few international automotive journos to savour the new Volt and the overall impression was positive. In a surprising departure from most launches, the journalists were requested to drive the Volt as slowly as possible to see how far they could travel on battery power alone. Most of them managed to cover about 75 km in 90 minutes. Even with the most spirited driving, the Volt simply refused to dip lower than 30 kilometres in the all-electric mode. In the engine-only mode, the overall mileage in real world driving conditions, as early tests suggest, is 14 km/l.
GM have also taken pains to ensure that the Volt feels more of a conventional vehicle. Touch-sensitive controls, reminiscent of early iPods, do everything from a-c to audio system control. A conventionally shaped gear shift slides between the common ‘Park, Reverse, Neutral, Drive, Low’ positions and there are three drive modes: Normal, Sport and Mountain. As with all EVs, flooring the pedal unleashes all the torque at once – 370 Nm in this case – making for whiplash-inducing starts from standstill. Naught-100 is achieved in nine seconds, not much by today’s standards but certainly far better than the Nissan Leaf or Toyota Prius.
Much of the development on the Volt was done by Saab while the propulsion system is based on GM’s new Voltec (formerly known as E-Flex) electric platform, which differs significantly from GM’s earlier BAS Hybrid and Two-Mode Hybrid systems. It goes into production this month in the US as a 2011 model with a price tag of Rs 18.2 lakh (before incentives).
CAPTION:
(Clockwise from top) The Volt could very well be the world’s most advanced electric/plug-in hybrid on sale now; charging time can be as little as three hours via a standard 240V outlet; the Volt’s interior is minimilastic and functional
