The range extender (or REx) version of the BMW i3 is obviously the sensible choice if you want one, since without the 600cc motorbike engine charging the battery, the pure electric one can only travel for around for a manufacturer claimed 81 miles or 129 km.

Now, we know just how much more sensible, since we have the first shot of the range extender’s efficiency sticker from the EPA. It reads 117 MPGe average, while its gasoline-only performance is still okay, rated at 39 mpg US combined (that’s 46.8 UK mpg or 6.03 l/100km).

Total range of the EV-only model is nearly doubled if you opt for the REx, rising to 150 miles (240 km), of which 72 can be all-electric miles, or the equivalent of around 115 km.

The extra weight of the internal-combustion engine does hinder its zero emissions driving somewhat, but it’s a compromise you have to think about making, if you’re serious about buying one of these i3s.

By Andrei Nedelea

Story References: Insideevs

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