The road to the BMW i3

The new BMW i3 is a cutting-edge piece of engineering, but its arrival in showrooms shows just how long the ‘cutting edge’ can spend in gestation before it is seen as viable for production.

Indeed, it is nearly 22 years since BMW’s first electrically driven urban concept appeared. After just 10 months’ development, the E1 was unveiled at the Frankfurt show in 1991, a concept with remarkable similarity to the new i3.

Just 3.45m long, it had space for four people and was built around an extruded aluminium spaceframe clad mostly in panels made from recycled plastics. A 32kW electric motor drove the rear wheels. Top speed was 75mph and 0-30mph took 6.0sec.

The 200kg, 19kWh sodium-sulphur battery was stored under the floor. BMW claimed it could be recharged in six hours from the mains for a 100-mile range. A second version was shown in 1993, with a more powerful sodium-nickel-chloride battery.

It’s thought that the E1 concept was not taken any further because California’s threat to force car makers to build electric vehicles never came to fruition. BMW also bought Rover Group in early 1994, curtailing a number of projects.

Another city car concept thought to have been a victim of the Rover takeover was the innovative Z13. Revealed at the 1993 Geneva show, the Z13 was also rear-engined.

The Z13 started as an unofficial project at BMW’s advanced Technik division under designer Robert Powell. He envisaged a compact, inter-city commuter car with an emphasis on high-end luxuries such sat-nav and a sophisticated audio system.

The final design was just 3.4m long and weighed 830kg. It used a central driving position, with the driver’s seat flanked by two passenger seats. Like the i3 and E1, the Z13 was based around an aluminium chassis. The rear wheels were driven by a 82bhp, 1200cc K1100 motorcycle engine, through a CVT ’box.

With the i3 concept taking two decades to reach the showroom, could a car similar to the Z13 be ruled out if a sub-Mini car looks like a viable new niche, especially in Asia?

To see more of BMW's previous electric concept cars, click here.