EDITOR'S NOTE: This story and headline have been changed to clarify that Tesla motors plans on producing the Model S sometime in the middle of 2012.
DETROIT – Tesla Motors plans to begin building the Model S electric sedan sometime in the middle of 2012 and expects to produce about 20,000 units annually, the company said at the Detroit auto show on Monday.
Tesla has booked more than 3,000 reservations for the Model S in North America and Europe. The car's expected base price is $49,000.
The Model S was announced in June 2008 as the less-expensive, higher-volume sedan to follow the Roadster and Roadster Sport. Tesla has sold about 1,500 Roadsters and Roadster Sport models through 14 dealers since deliveries began in February 2008.
Meanwhile, Tesla unveiled at the show a Model S unibody equipped with suspension, battery and powertrain components. The unibody showed the sedan's lightweight aluminum structure. High-strength steels are used only for reinforcement in key areas, such as the front and rear bumper bars.
The 2012 Model S is rear drive. The compact electric motor and transmission assembly — much smaller than a conventional internal combustion engine and gearbox — is mounted behind the rear axle line and under the trunk floor. More than 7,000 lithium ion battery cells are packaged in a reinforced structure that helps comprise the vehicle's floorpan. Cargo volume exceeds 30 cubic feet thanks to functional front and rear luggage areas.
The Model S has three options for battery packs, allowing customers to select from a standard 160 miles per charge, to upgraded arrays capable of 230 and 300 miles per charge.
Construction techniques will include traditional welding and riveting. To save weight, some elements will be fastened using high-tech adhesive systems. These bonding construction processes are also used for the Jaguar XJ and Audi A8, both considered lightweight vehicles in their respective classes.
Toyota has invested $50 million in Tesla Motors. Tesla, with Toyota, will produce all future Tesla models at the former NUMMI plant in Freemont, Calif. Roadster production will not move from the current Menlo Park, Calif., facility to Freemont because that model will be phased out in 2012.