It’s been rumored since about 2012 that BMW would eventually plug the gap between the i3 and i8 bookend models of its eco-focused i range with a new model dubbed the i5.

We first heard that the vehicle would be something akin to a small van, but then we starting hearing that the car would be a large sedan designed to take on Tesla Motors' [NSDQ:TSLA] Model S. Now we’re hearing about yet another potential bodystyle for the i5: an SUV.

Although an i5 SUV is yet to be confirmed, Auto Express has information from insiders at BMW that an SUV bodystyle is shaping up to be the most popular option for the vehicle. This makes sense as the SUV segment has the greatest potential for growth in the coming years, especially in China where there are also substantial incentives for zero- and low-emission vehicles. Germany is also looking at incentives to help get its electric car sales up to a million units annually by 2020.

Tesla’s Model X, though more of a high-riding hatch than an SUV, is already available and Audi has confirmed plans to launch an electric SUV by 2018. Rival luxury marques Jaguar and Mercedes-Benz are also thought to be looking at electric SUVs of their own.

Whatever bodystyle the i5 ends up featuring, one thing is clear: BMW plans to offer much more zero-emission vehicles. As the automaker’s sales and marketing Ian Robertson explains it, “legislation means we’ll inevitably have more zero-emission cars and we’re exploring more i models.