As a plug-in full hybrid with a turbodiesel engine, upward-pivoting doors and radical styling, BMW's 4- seat Vision EfficientDynamics concept car—now on display at the Frankfurt auto show—is packed with technology enabling it to be both frugal and fast.Complementing the Vision’s futuristic exterior styling, the interior of the car has a flowing instrument panel and a seating arrangement designed to give the passengers a floating-in-air feel. The upholstery is mostly made with natural materials although Kevlar is used for the seats. New technology such as a 3- dimensional head-up display and BMW night vision is included.
The chassis of the Vision EfficientDynamics Concept is constructed mostly from aluminum, with the roof and the exterior body made almost entirely from a special polycarbonate material. The car is 181.1 in. long, 74.8 in. wide and 48.8 in. tall. It has a 2+2 seating configuration that includes 5.3 cu. ft. of luggage space.
The Vision concept is powered by three sources: two electric motors (one at each axle, giving the car all-wheel drive in electric mode) and a turbodiesel engine (in front of the rear axle). The synchronous electric motor in front can provide a continuous output of 80 horsepower and peak torque of 162 lb.-ft. via a two-stage, single-speed reduction gearbox. For that extra kick needed when passing, the same motor can deliver 112 hp for up to 30 sec., and up to 139 hp for 10 sec.
In back, the second electric motor resides between the mid-mounted turbodiesel and BMW’s 6-speed DCT twin-clutch gearbox driving the rear axle. It is rated to serve up 33 hp continuously (51 hp peak) and maximum torque of 214 lb.-ft. Combined, the two electric motors can carry double duty in propelling the car, or serve as regenerative powerplants to recharge the onboard lithium-polymer batteries.
There are a total of 98 lithium-polymer cells that sit in the middle of the car running from front to back. Each individual 30 amp-hr cell can deliver 600 amps at 3.7 volts. And when that extra passing power is needed, each cell can ramp up to provide 1200 amps. The entire battery pack weighs about 190 lb. The onboard computer keeps the lithium-polymers at optimal operating conditions by using up to 80 percent of its discharge capacity (10.6 kWh total) when the car is in motion.2009 Frankfurt auto show BMW Vision EfficientDynamics concept
BMW Vision EfficientDynamics concept
The rear/mid-mounted direct-injection, 1.5-liter 3-cylinder turbodiesel puts out 163 bhp and 214 lb.-ft. of torque. Combined with the electric motors, the total system output is 356 bhp and 590 lb.-ft. of torque, giving a level of performance that BMW says is "superior to anything provided so far by a hybrid vehicle."
Not totally relying on the turbodiesel engine, the Vision EfficientDynamics also features a plug-in solution where the batteries can be recharged in 2.5 hours when connected to a 220-volt 16-amp outlet. With a 380-volt 32-amp electric source, the charging time can be as little as 44 minutes. Running in full electric mode, the car can travel up to 31 miles. With only the turbodiesel providing power, an approximate 400-mile range can be obtained using a 6.6-gallon tank.
In the European Union test cycle, aided by the car's aerodynamic shape (its drag coefficient is just 0.22) and narrow tires for a sports car — 195/55s on 21-in. wheels—the Vision is able to achieve a fuel economy rating of 3.76 liters/100 kilometers (62.5 mpg equivalent), with CO2 emission recorded at a low 99 g/km.
Due to the car's considerable power and relatively low curb weight of 3076 lb., BMW claims the Vision EfficientDynamics concept can hit 100 km/h (62 mph) in 4.8 seconds, and easily exceed its electronically limited top speed of 155 mph.
Leave it to BMW to figure out a way to make hybrids exciting.
