Plug-in Vehicles Proliferate

Full battery-electric and hybrid-electric plug-in vehicles will start hitting the streets in significant numbers later this year

4 min read
Illustration of a plug-in-car.
Illustration: Paul Tebbott

Do you own a plug-in car? Do you even know anybody who does? Probably not. But that might very well change this year. Electric cars aren’t new, of course. Mitsubishi’s all-electric i-MiEV has been available in several countries since 2010. The US $35 200 Nissan Leaf, another pure electric vehicle, has been selling in Japan and the United States for more than a year. The Chevy Volt is also available in America, as is the Tesla Roadster, a $109 000 toy for the rich.

graphic link to special report

And yet, despite the intense press coverage and feverish anticipation, relatively few of these cars have found their way into garages and driveways. In 2012, however, a big influx of plug-in cars will help these vehicles start shedding their novelty image and in some places may even justify the construction of public charging stations [see “State of Charge,” in this issue].

By the end of 2012, for example, Toyota will introduce no fewer than three new plug-in models, and Ford and Volvo will both have their first-ever plug‑in electrics in showrooms. Nissan and General Motors will ramp up production of the Leaf and the Volt as well. Nissan aims to produce about 4000 Leafs per month at its plant in Oppama, Japan. Capacity will rise by another 150 000 cars annually when modifications to Nissan’s assembly plant in Smyrna, Tenn., are completed later this year, the company says. And Nissan projects that further production increases in 2013 will bring the total to about a quarter million cars a year, which is on par with the number of Volkswagens of all types sold in the United States. If Nissan achieves that kind of volume, the Leaf will have truly broken out of its niche, becoming the Prius of pure electrics.

Chevy’s Volt, which costs a little more than $39 000, will also be seen in far greater numbers. Production of the Volt, which last year totaled about 5000 cars, is slated to rise to 60 000 in 2012, with some being sold outside North America.

Even Tesla is trying to go mainstream. This past October, the California carmaker showcased beta versions of an all-electric sedan, the Model S. At $57 400, it ain’t cheap, but it’s much less pricey than the Roadster.

To scale up its operations, Tesla acquired the New United Motor Manufacturing plant, in Fremont, Calif., where General Motors and Toyota formerly built cars. Tesla projects that later this year, Model S vehicles will be made there at a rate of 20 000 per year.

Much of the money to buy that factory and get it tooled up came from the initial public offering of Tesla stock, which raised $226 million for the company in June of 2010. Just weeks before the IPO, Tesla and Toyota agreed to collaborate on the development of electric vehicles. The two companies began by working on an all-electric version of Toyota’s RAV4, an SUV. Commercial versions of that vehicle will be produced later this year alongside conventional RAV4s at Toyota’s assembly plant in Woodstock, Ont., Canada.

This is not the first time the RAV4 has been electrified. Between 1997 and 2003, Toyota produced an earlier battery-powered version of this car, some 1500 of which were sold or leased in California. The later ones included a 27-kilowatt-hour nickel metal hydride battery pack, which provided a range of approximately 160 kilometers.

chart showing plug-in EV sales, U.S.

The electric RAV4 design that Toyota and Tesla have worked out will have a similar range but much better acceleration and top speed. That’s because it will incorporate Tesla-made drivetrains, including the same kind of battery modules [PDF] found in the Roadster and the Model S. These modules are unique among electric cars in that they contain thousands of thumb-size lithium-ion cells—the kind you might find inside your laptop.

Although other car manufacturers are now also using lithium‑ion batteries to power their plug‑in vehicles, they construct battery packs using a smaller number of large-format cells. The Leaf’s 24-kWh battery, for example, is composed of 192 cells. And the electric version of the Ford Focus, which debuts this year, uses a 23-kWh pack of just 98 cells.

Toyota’s decision to use Tesla’s many-thousand-cell battery modules for its electric RAV4 is a puzzle. Toyota will be selling two other plug-in vehicles in 2012—an all-electric version of the diminutive Scion iQ and a plug-in version of the company’s well-known Prius hybrid—and their battery packs will have the more standard configuration. Why go with something so different for the new RAV4 EV?

Sheldon Brown, executive program manager at the Toyota Technical Center in Saline, Mich., explains the reason for the dueling battery technologies. “We see this as an opportunity to challenge our current way of thinking and to reevaluate our own development processes, ensuring that we are not complacent,” he says.

You can make a strong case that the likeliest to succeed is the plug-in Prius, which will go on sale in Europe, Japan, and the United States early this year for $32 000. The reason? It breaks from established technology the least.

The car is essentially a clone of the company’s third-generation Prius hybrid. But in place of the latter’s 1.3‑kWh nickel metal hydride battery, the plug-in model contains a 4.4‑kWh lithium-ion battery. This battery can propel the car for about 24 km without help from the car’s gasoline engine. That limited electric range leaves some plug-in proponents underwhelmed—the Chevy Volt, by contrast, squeezes about 60 km from its battery.

But Mike Ferry, transportation program manager at the California Center for Sustainable Energy, in San Diego, likes the new Prius. He and his coworkers took part in the demonstration and testing program Toyota mounted last year using preproduction versions of this car. Ferry let many of his colleagues use these plug‑ins to see how they’d fare. "We have people who live 6 or 7 miles away—all urban driving. They were able to go all week without the gas engine coming on," he says. Most couldn’t do that, but on average, his group burned less than 3 liters per 100 km (between 80 and 85 miles per gallon), almost doubling the efficiency of the fuel-sipping regular Prius.

Toyota expects to be able to produce 50 000 plug-in Prius cars annually. While that’s a modest number compared with sales of the conventional Prius, which exceed 400 000 cars a year, it’s yet another sign that plug-in vehicles are finally going places.

This article originally appeared in print as “Plug-ins Proliferate.”

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