The i3 is not a regular car that just happens to be fitted with an electric motor and battery. It was designed to be different, with an aluminum tub under a carbon fiber body (weight is the enemy of energy). The interior uses sustainable materials. Range is 81 miles (a 2017 update should bring that to 114 miles), a 240-volt charger needs just four hours for a full top-up, and the electric motor sends 170 horsepower and 184 lb-ft of torque to the rear wheels at a rate of 124 MPGe. A range extender (a 600 cc flat twin engine from BMW’s motorcycle division acting as an on-board generator) is optional.