BMW Unveils Triple Threat Plug-In Sports Car

BMW's Vision EfficientDynamics concept has been the subject of rumor and innuendo for weeks, but now the German car company is setting the stage for its 2009 Frankfurt Auto Show display with new details of its concept.


As the name implies, this concept car grafts fashionable green technology on the body of a 2+2 sports car. The promise: BMW M-car performance from a vehicle with a three-cylinder diesel plug-in hybrid powertrain.

To break down everything in that last clause takes some effort. The combination of fewer cylinders, plug-in hybrid technology, lithium-ion battery cells, and diesel combustion is a technological tour de force, should it ever reach production. It's a holy grail for green-car drivers that melds the state of the art in lower-consumption driving in ways that haven't made the step from engineering lab to the street quite yet.


The drivetrain marries a direct-injection, 1.5-liter, 163-hp, three-cylinder turbodiesel to two electric motors (one per axle), a set of lithium-ion batteries and a software controller that modulates and marries both powertrains to a combined total of 356 horsepower and 590 pound-feet of torque. Using only the diesel engine's power, a six-speed dual-clutch transmission sends power to the rear wheels. The hybrid powertrain is less conventional: it's actually two distinct applications, a hybrid system on the rear wheels and a hybrid motor on the front wheels. The rear-wheel hybrid system operates in tandem with the diesel engine, while the front system operates on battery power alone. With this arrangement--similar in concept to the Ferrari hybrid system announced earlier this year--the Vision EfficientDynamics could provide all-wheel drive in electric-only mode, with battery power twisting its front and rear axles simultaneously.

Performance is geared to please the toughest Bimmerphile. BMW claims a 155-mph top speed and a 0-60 mph time of less than 4.8 seconds, while providing fuel economy of almost 63 mpg, and for European enthusiasts, CO2 emissions of 99 grams per kilometer.

Because it's also a plug-in hybrid, those controversial CO2 emissions could be halved to 50 grams per kilometer, if the Vision EfficientDynamics were juiced up with electricity and driven on battery power alone. The plug-in technology used means the concept car would use a standard 220-volt household outlet to recharge its batteries. A 2.5-hour recharge time is predicted, though on a 380-volt line, BMW says a 44-minute full recharge is possible.

Driving range could pass 400 miles with fuel or 31 miles on electricity alone, BMW also adds.

A grand tourer in silhouette, the concept wears aerodynamically influenced cues for style and purpose. A low front end and active louvers cool the drivetrain when needed, and close to improve airflow when unnecessary. The racing-inspired details continue with well-managed airflow--so tightly tuned, the EfficientDynamics concept generates a coefficient of drag of 0.22, while today's best production cars sit at 0.24 (the Mercedes-Benz E-Class Coupe).