The amazing electric sports car, the Tesla Roadster.

Reviews of cars, trucks, and other autos.
Nov. 27 2006 6:57 AM

It's Electric!

The Tesla Roadster—a hotshot sports car that runs on batteries.

Tesla Roadster. Click image to expand.
Tesla Roadster

A week ago, I went for a spin in the fastest, most fun car I've ever ridden in—and that includes the Aston Martin I tried to buy once. I was so excited, in fact, that I decided to take a few days to calm down before writing about it. Well, my waiting period is over, I'm thinking rationally, and I'm still unbelievably stoked about the Tesla.

The Tesla Roadster won't hit the streets until next year. If you see one on the street, then, you should ask for a ride. Even from the passenger seat, the car feels impossibly stronger, faster, and safer than it should be. The trick is Tesla's torque curve—the arc of the motor's strength as it revs from a standstill to top speed. Compared to gasoline-engined cars, the Roadster's torque curve feels—and is—impossible. That's because the Tesla's motor is electric.

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I've always marveled at how long the antique internal-combustion engine has survived. By 2006 standards, my car's power plant is a noisy, heat-blasting, poison-spewing monster with way too many moving parts. One spin in a Tesla made me realize that the gas engine might finally be on its last legs—and not because electric cars will help wean us from Saudi oil and save us from global warming. Rather, the Tesla Roadster is a rolling demo that proves electric cars now outperform their gas-guzzling counterparts in comfort, convenience, and, best of all, speed.

Electric motors differ from gasoline engines in lots of ways, but the torque curve is the most startling. In a car with a gas engine, you press the accelerator, the engine rotates faster, and its torque output rises to reach a somewhat-flat plateau. At that point, the car accelerates smoothly as the engine spins ever faster. Eventually, the torque starts to fall off, and it's time to drop the engine's speed back below the sweet spot, shift up to the next gear, and start over. Why do sports cars have so many gears? To make sure the engine is revving in its maximum torque zone at just about any speed. Spin it too slow, though, and the engine stalls.

The motion in a gas engine comes from repeatedly compressing and exploding a mix of fuel and air in one piston after another. In an electric, by contrast, motion is generated from the constant magnetic force created when electric current runs through wire coils inside the motor. As a result, the torque curve comes on at full strength as soon as an electric motor begins to spin—its maximum torque is at 0 RPM—and fades in a fairly constant curve as it spins faster. You don't need to idle it to keep it running. You can see the difference between electric and gasoline torque curves in this chart. Get in a Prius and press the pedal, and you'll feel it—instantaneous and silent, smooth and steady.

What's the upshot of all this? A hotshot driver who masters the skill of coordinating gas pedal, clutch pedal, and shift lever can take a 500 horsepower Corvette from standstill to 60 miles per hour in four seconds. You—and I do mean you—could do the same thing in a Tesla. Just stomp your foot down.

It's one thing to know this stuff in theory. It's another to experience it on Highway 101. That's where I hitched a ride with Martin Eberhard, the Roadster's inventor. Eberhard got behind the wheel of a Tesla prototype and put the pedal to the metal. I was flabbergasted. In the passenger seat, I was wrapped in an all-powerful force that launched me forward with a perfectly even push. I've been driven this fast before in high-end European cars, always with a mix of excitement and omigod we're all going to die. But as Eberhard zoomed around slowpoke trucks and shot into traffic openings, I never once flinched with worry. I thought I'd miss the sexy rumble of a well-honed engine, but I didn't. In the silence I felt less distracted, more alert on the road. No lurching, no racket, no hesitation—this is why accountants buy Beemers to commute.

Eberhard is that unsung breed of Silicon Valley genius: the hardware engineer. I crossed paths with him briefly 15 years ago when we both worked for a startup that made computer workstations. It was obvious he was the company's secret weapon. He went on to launch one of the first e-book readers, then used his buyout money to build electric cars. Tesla operates more like a consumer-electronics maker than a traditional auto manufacturer. The company's headquarters are in the Valley, where a team of designers creates specs for parts that are manufactured and assembled around the world. The first batch of cars is being assembled in England by Lotus, a small-volume sports-carmaker.

Eberhard says traditional carmakers have failed with electrics for two reasons. First, they market them as "penalty boxes" for environmental do-gooders and gas-mileage-obsessed penny-pinchers. Second, they just don't understand batteries. The Tesla's giant lithium-ion battery pack gives it the power to hit 60 in four seconds, to run 250 miles without a recharge, and to charge rapidly at its home charging base (a one-hour charge will take you 80 miles; it takes a 3.5-hour charge to go 250 miles). You can even plug into a wall socket at a roadside stop in a pinch. That makes the Roadster a viable commuter car and weekend day-tripper. The company claims energy costs as low as a penny per mile.

The two-seat debut model, a $100,000 pop-top sports car about the size and shape of the Lotus Elise, has room for two people and a set of golf clubs but not much more. Tesla is working on a 2009 model  aimed at competing with BMW's 5-series, a $50,000 to $75,000 sedan with room for five adults and a full-sized trunk. It may also license the electric-motor tech to other carmakers—an all-electric Prius isn't out of the question.

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