Launching early next year, the 2015 BMW i8 plug-in hybrid sports coupe is the second stage in BMW's i-car program, dedicated to vehicles with electric drivetrains.

While it isn't a full battery-electric vehicle (or range-extended EV) like the i3 city car, electric power is still an important part of the i8--in its performance as much as its efficiency.

That much is clear with BMW's latest video, following on from the laser headlight demonstration we covered yesterday.

BMW says that the i8 will be a proper driver's car not despite the hybrid element, but because of it--and given the touted performance figures, it's hard to argue.

You may already be familiar with the i8's layout. The mid-engined setup uses a 1.5-liter, three-cylinder Twincharged gasoline engine to supply most of the motive power. It's a brand-new engine also set to power the new MINI Cooper and a selection of smaller BMWs in the years to come.

It's surprisingly powerful for such a tiny, lightweight engine--developing 231 horsepower and 236 pounds-feet of torque.

That it's supplemented by a 131 horsepower, 184 lb-ft electric motor on the front axle is a major contributor to impressive levels of performance.

With a combined 362 horsepower, BMW quotes a 0-62 mph sprint of 4.4 seconds. That's barely slower than the Audi R8 e-tron we drove in Berlin earlier this year, and also in the Tesla Model S ballpark--so the i8 is no slouch. Top speed is higher than either the Audi or Tesla, at 155 mph--no doubt thanks to the gearing required by the gasoline engine.

The electric motor also helps eliminate any throttle lag you might have experienced with the turbocharged engine--so it should be responsive too.

The great unknown for the moment is real-world fuel economy. It's safe to assume that the i8 will show off some quite surprising figures, though we've got used to plug-in hybrid real-world economy fluctuating hugely--it really depends just how much you use the electric power.

Even so, in a relatively lightweight, sleek and small-engined vehicle like the i8, we're expecting big things.


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