Were it not for imminent reveals at the 2011 Frankfurt Motor Show in mid September, you might think the automakers were getting careless with their upcoming models.

First, Audi's E1 e-tron was caught on camera in the center of Berlin, being filmed in camoflage for an Audi promotional video. The E1 was then officially revealed in sketch form the very next day.

Now, the 2014 BMW i3 electric city car has been spotted rolling silently down Wacker Drive in Chicago, joined by a tracking vehicle filming it for an impending BMW video. Unfortunately it doesn't give us any more idea what the full production version of the i3 might look like, but the concept certainly stands out against a city background.

The 2014 BMW i3 is one of two cars BMW has revealed as part of it's "i" car lineup. The i3 concept is an all electric urban minicar with a rear-mounted 170-horsepower electric motor, powered by lithium-ion batteries. Range is estimated at 80 to 100 miles, which isn't half bad considering the 7.9 second 0 to 62 mph acceleration and 93 mph top speed.

The other "i" car BMW revealed is a plug-in hybrid sports coupe. The 2014 BMW i8 is an altogether sleeker object than the i3 and uses a 223 horsepower, 1.5-liter turbocharged 3-cylinder gasoline engine powering the rear wheels, and a 131-horsepower electric motor powering the front wheels. All electric range should be 20 miles at city speeds and performance will be as exciting as you'd expect from a BMW sports car.

The two concepts will be on display at the 2011 Frankfurt Auto Show.


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