Luque says Renault decided that the capacity of the Zoe's battery would be 22 kilowatt-hours based on how much space it could make for it in a small car. He adds that three advances in efficiency enabled his team to extend real-world range by 20 to 30 kilometers.
First, Zoe carries the first automotive heat-pump heat and air-conditioning system, capturing heat outside and pumping it into the car rather than simply heating a resistor, as other electric vehicles do. This means that the Zoe can deliver three kilowatts of heat while drawing just one kilowatt from the battery.
The two other range-extending innovations are a low-friction tire from Michelin that is making its commercial debut with the Zoe, and a braking control system that senses how hard drivers hit the pedal and keeps the conventional friction-pad brakes idle unless it detects a need for strong braking. As a result it maximizes the use of the regenerative braking, whereby the car's electric motor operates as a generator to pull energy from the car's momentum and thus recharge its battery.
The Zoe's impressive range comes at a key moment for Renault and its corporate partner, Nissan. The Renault-Nissan Alliance has staked its future on the electric car since pushing heavily into battery-powered vehicles five years ago. But sales have cooled this year for Nissan's flagship EV, the Leaf, and it faces growing complaints from customers over the vehicle's range (see "Air Air-Cooled Batteries Hurting Nissan Leaf Range?").
Nissan originally claimed the vehicle would deliver 100 miles of travel on a full charge, but the EPA rated it for 73. Meanwhile some customers are complaining that they're getting even less mileage, which Nissan attributes to higher-than-average use of the battery in unusually hot areas such as Phoenix.
This kind of customer dissatisfaction is part of Toyota's argument for focusing on hybrid vehicles, which have gasoline engines that extend their range to 500 miles or more. "The market is not ready and the technology is not ready for pure electric vehicles as a mass vehicle," says Gerald Killmann, Toyota's director for powertrain R&D in Europe. He says that the eQ would cost about 36,000 euros if sold outright (Toyota plans to lease the 100 it is making). But that is about 50 percent more than Renault is asking for the larger Zoe, and the eQ's 12-kilowatt-hour battery packs 45 percent less energy.
Killmann's pricing figures would suggest that Renault is taking a loss on the Zoe. But Luque, for his part, insists this is not the case: "Our bosses never allow us to make a business case where we're losing money."
German automakers are also countering Toyota's pessimism on the viability of electric vehicles. Daimler, in particular, unveiled three new ones at the Paris show. One of those is an electric version of Smart's two-seat ForTwo, which the Daimler subsidiary started producing in June. Pitt Moos, product manager for the Smart Electric Drive, says it delivers a 145-kilometer range.
Moos adds that if any producer can manage to squeeze a profit out of small EVs, it will be Renault. That explains why his firm is teaming with Renault to develop a four-seat version of the Smart to be sold in 2014 or 2015. "Renault makes cheap cars and knows how to make money from them—something that Daimler has never learned," he says.
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