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This past September, at a race in Beijing, China, Germandriver Nick Heidfeld was coming up fast on leader Nicolas Prost of France. On the final lap, Heidfeld attempted a pass but clipped Prosts car. Instantly, Heidfeld veered left, hit an embankment, and soared into the air. His car flipped and

slammed into a shock-absorbing divider, shattering sections of the vehicle. Moments later, Heidfeld emerged unharmed.

The two drivers were part of the first-ever Formula E event, a racing series featuring only electric cars. Although the accident was terrifying, it did help answer one of the questions about Formula E: whether its battery-powered vehicles can deliver the same serious

thrills as other motor sports, like NASCAR or Formula 1 (FI).The first Formula E season will feature nine races,

including events in Miami, Florida, in March and Long Beach, California, in April (see map, beloiv). The host

cities determine the roughly 2-mile-long tracks, then clear the streets for the day. During the main event, the drivers

will complete 32 laps of the course, cruising at speeds up to 225 kilometers (140 miles) per hour. Though the race lasts just

one day, it took years of research and engineering to prepare the vehicles for these battery-powered sprints.

POWER-PACKED CAROne of the main misconceptions about electric cars is that

theyre slow. Ron Matthews, a professor of mechanical engineering at the University of Texas, explains that when compared with a traditional engine, the electric

motor is actually better suited to accelerationthe change in velocity over time.

In a standard engine, a spark ignites the gasoline, and the energy from these small explosions drives mechanical rods

Continued on the next page >

WORLDWIDE RACERSThe first season of Formula E is composed of nine races,

on city streets on four continents around the globe.

called pistons up and down. Through a series of additional steps, the pistons eventually turn a cylindrical shaft. Their energy is converted into rotational energy, called torque, used to spin the cars wheels.

With an electric motor, the transfer of energy is much simpler. There are no pistons: Magnets inside the motor spin a single shaft, which generates torque immediately. Electric motors generate a whole lot of torque at low speed, says Matthews. That allows battery-powered cars to accelerate extremely well from a stop.

Formula E vehicles can go from 0 to 97 km (60 mi) per hour in three seconds, only about one second slower than gas-fueled race cars.The reason an electric car accelerates a little more slowly than a gas-powered car is the battery, says Matthews. Batteries are heavy, he explains. The motor has to work harder to push that added weight, so the cars arent quite as fast off the starting line as the lighter, gas- powered vehicles.

DESIGN CHALLENGESUnlike FI teams, which build

customized cars to gain an edge over the competition, the drivers in the Formula E series all use the same vehicle, designed by the French company Spark Racing Technology. Theophile Gouzin, an engineer at Spark, says not only was the added weight of the batteries an obstacle during the design process, but their size was a problem too. Fitting the battery case into the car was a real challenge, Gouzin says.

The case holds 150 lithium-ion batteriessimilar to those used in laptops. Combined, these batteries store as much energy as 10,000 standard AA batteries. But the battery pack takes up space that would normally be used for the structural, weight-bearing parts of

WINGLETS *LTo re d u c e d rag , sm all ae ro d y n a m ic w ings ch a n n e l a ir over th e c a r s su rfa ce , a llow ing air to rush beh ind th e veh ic le .

the carthe equivalent of the beams in a building. So rather than adding parts around the battery case to support the car, designers made the case itself a structural piece of the car. The vehicle is all designed around the battery, says Gouzin.

PUSHING THE LIMITSSpark designers also had to find

ways to overcome various factors that affect the race car at high speeds. Aerodynamic draga force that acts on an object to slow it down as it moves through air becomes more powerful as a car goes faster. The Formula E vehicles have curved bumpers that send airflow up and over the front tires. There are also miniature wings called winglets on either side of the drivers seat that channel air over the cars surface to reduce drag (see Inside the Formula E Race Car, right).

Another factor is centrifugal force, the same phenomenon that pushes you against the wall of the spinning Gravitron ride at amusement parks. When Formula E drivers speed around tight city comers,

they have to balance their desire to go as fast as possible with the pull of centrifugal force. If they go too fast, the car could flip. Thankfully, the drivers seat is very close to the ground. This gives the Spark a low center of gravitythe spot where the mass of the vehicle is focused to help keep the car on the road, explains Matthews.

All these design choices helped

STEERING WHEELD rivers u se th e s teerin g w h e e l to c h a n g e g e a rs an d to m a n a g e th e c a r s to rq u e to co n se rve b a tte ry power.

INSIDE THE FORMULA E RACE CAR

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make a fleet of extremely fast electric cars. Still, some racing fans arent sold on the new sportwhich they say is too quiet. Spectators used to the roar of FIs gasoline engines arent thrilled with the mellow purr of the electric motors.

pushing the technological limits of electric vehicles.

In fact, technological competition is going to become part of the sport in upcoming seasons. All drivers will still get behind the wheel of similar vehicles, but each team will

For now, though, its all about the drivers skills. The Spark might not be loud, but it still demands the talent of top racers. Driving these cars through city centers is still a very difficult task, says Gouzin. &

Greg M oneOthers argue that the Spark

shouldnt be compared to FIs cars. The point of the series, they say, isnt just the race. Its also about

be allowed to improve the battery system of its car. So in the years ahead, it may be that the car with the best battery wins.

DOWNFORCEInstead of generating lift, like an airplane wing, the aerodynamic bumper channels air down so it presses the speeding car to the road.

LOW RIDE The driver sits close to the ground, partly to reduce drag. Air flows around and over the driver instead of pushing into him or her, which would slow the car.

BATTERY LIFE W r -The 150 lithium-ion cells in the battery pack last for roughly |M half the race. Recharging mm S would take more than an hour, and the batteries are too hard to swap out because of the mm way their cases are built into I the structure, so drivers switch to an identical fully charged car when power runs low.

COOLINGInside the battery pack, a liquid cooling system draws heat away from the electronics.

TIRESGrooved, all-weather tires maximize friction and increase the cars grip on the road.

MOTOR *-----------------The electric motor provides less than half the power of a traditional F1 engine, but that's enough to accelerate the vehicle to speeds of 140 miles per hour.

FANBOOST S t V ,The three drivers who receive the t most votes from fans prior to the ^ race can activate a feature called FanBoost. This increases the motors horsepower by 20 percent I for five seconds, allowing them to blow past their rivalsbut drivers are allowed to use it only once per race.

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