MINI's electric prototype has been spied again. Most prominently clear in its absence is any form of exhaust piping at the rear, pointing to a fumeless powertrain.

MINI is playing electric catch-up to players like Nissan who are already testing full-on electric vehicles. Nevertheless the Brits aren’t letting their late start hamper their progress. We’ve spotted this all-electric MINI before under a heavy cloud of camouflage, but this is the first time we’ve seen it seriously dressed down in that department.

Most prominently clear is the rear which shows no exhaust pipes at all, which either means side breathers ala SLR McLaren or no fumes to speak of. Since there’s nothing on the sides we can safely confirm electricity running through this MINI’s pipes. The stickers on the sides and rear don’t exactly keep a subtle tone either.

Five hundred of these will be running about, mostly in California (490 to be precise) in order to truly test the car’s compatibility with some of the world’s strictest environmental laws.

Gallery: All-Electric MINI Cooper Prototype Sheds Its Minimal Disguise