NEW YORK -- BMW of North America will equip its initial U.S. shipment of i3 electric cars with an optional gasoline engine to extend the vehicle's range, if needed, CEO Ludwig Willisch said.
With the extender, the i3's range will nearly double, to between 160 and 200 miles before the car needs a recharge, BMW executives said.
The i3 five-door will have an optional two-cylinder, 0.65-liter gasoline motorcycle engine and an auxiliary generator that charges the battery, said Willisch.
Prices for the car and the range extender have not been disclosed.
Similar to the engine in the Chevrolet Volt, the small gasoline engine will drive a generator that produces electricity for the i3 drivetrain, said Willisch.
"All it does is charge the battery and it typically kicks in only if the battery is discharged," he said.
The car's performance will be affected when the gasoline engine is in use, he said. "The car will not be as agile," Willisch said. "It will not have full power when it runs on the combination."
The gasoline engine will be housed in the trunk and connected to a generator that recharges the battery, but will not transmit mechanical power directly to the wheels.
Although the range extender will be optional, Willisch expects a minimum take rate of "80 percent."
The carbon-body i3 goes on sale in the United States late this year. There won't be a significant number of cars in dealerships until early 2014.
BMW will offer the extender even though leasees of its two prior electric cars, the Mini E and the Active E, did not express concern about the 100 mile range the cars can travel on a charge, said Willisch.
Even so, with the i3, "we will typically order most of them with range extenders," Willisch said.
BMW executives wouldn't disclose additional technical specifics about the i3 extender.
The i3 will be the first of two plug-in vehicles BMW plans to market in the United States.
The i8, a hybrid sports car, will go on sale in early 2014. It will have an electric motor and a 1.5-liter twin-turbo three-cylinder engine, Harb said.
Jacob Harb, head of electric vehicles and strategy for BMW, said service and technical dealership employees will be trained on how to service and repair the i3 and the i8 hybrid sports car in the second half of the year.
"We already have 64 dealers capable to service the electric car," said Harb.
Those 64 dealers service the ActiveE -- BMW's second electric car, which has been undergoing trials since last year. BMW has leased 700 of the ActiveE, based on the 1-series coupe, in New Jersey, New York, Connecticut, Boston and three California cities. The ActiveE two-year leases expire in 2014.
Before the ActiveE, Mini ran a trial with 450 electric Mini Coopers in 2010 and 2011.