The striking BMW Vision EfficientDynamics hybrid concept was unquestionably the star concept of September's Frankfurt Motor Show.

It proved, once again, that when German carmakers turn their minds toward a new goal--in this case, a sports car with breathtaking fuel efficiency--they can produce audaciously good concepts that often end up as production cars.

M1 for the new century?

And now it looks like the EfficientDynamics hybrid sports coupe too will be offered for sale, starting in 2013, at a projected volume of 5,000 to 10,000 copies a year.

Reports say BMW is viewing the car in the vein of its legendary M1, its first mid-engine two-seater sports coupe, of which just 450 were made between 1978 and 1981. It also appears that the cumbersome compound name will, thankfully, exit stage right.

The goal of the Vision EfficientDynamics concept was to provide "the performance of an M vehicle" paired with extreme fuel efficiency.

Three cylinders? A diesel ?!?!?

So rather than the classic BMW straight six, it uses a tiny turbocharged 1.5-liter three-cylinder diesel engine, mounted at the rear and putting out 163 horsepower.

But there's more: A 10.8-kilowatt-hour lithium-ion battery pack powers a pair of electric motors, one for each axle, that give a combined total of 356 hp and a stunning 590 foot-pounds of torque. It is, in fact, a full plug-in hybrid powertrain.

Using standard European 220-Volt power, the pack could be fully recharged in two and a half hours. The time falls to 44 minutes using a special, higher-power 380-Volt line.

BMW Vision EfficientDynamics Concept, 2009 Frankfurt Auto Show

BMW Vision EfficientDynamics Concept, 2009 Frankfurt Auto Show

2009 BMW Vision EfficientDynamics Concept

2009 BMW Vision EfficientDynamics Concept

2009 BMW Vision EfficientDynamics Concept

2009 BMW Vision EfficientDynamics Concept

Electric all-wheel-drive

In its all-wheel-drive system, the wheels at the rear are driven by a combination of electric power and engine torque. The engine drives through a six-speed dual-clutch transmission.

But the front wheels are driven solely by electricity, and the powertrain could permit fully electric all-wheel-drive, qualifying the Vision EfficientDynamics for entry into the zero-emissions zones envisioned for city centers of the future.

60 mph in less than 5 seconds

BMW claims that this highly unlikely powertrain provides a 0-to-62-mph time of 4.8 seconds, along with a top speed of 155 mph. The range on electricity alone is up to 31 miles, BMW says.

And how about gas mileage of more than 60 miles per gallon? (Depending, as always for plug-ins, on the details of the specific usage cycles.)

Uber-aerodynamic

The body shell and suspension of the EfficientDynamics concept are made of aluminum, to minimize weight, with seat frames in Kevlar. The roof and door skins are lightweight transparent polycarbonate, which darkens in the presence of light, just like photochromic glass.

The car's drag coefficient is just 0.22, versus 0.24 for today's most aerodynamic production car, the 2010 Mercedes-Benz E-Class coupe.

And its dimensions position the EfficientDynamics concept solidly in the middle of today's BMW coupe range. It's 181 inches long, 75 inches wide, and 49 inches tall, weighing just slightly over 3,000 pounds.

[Inside Line via Motor Authority]