Development of Porsche's first electric car has now started, as the company transforms its Mission E concept into a zero-emissions sports car of the future. The production version is expected to go on sale in 2020.

Revealed in September 2015, the Mission E is a four-seat sports car powered by two electric motors producing over 600 horsepower. The car, to offer a sportier alternative to the electric Tesla Model S, is said to have a maximum range of 330 miles, more than the Model S currently achieves, and sprints to 60mph in 3.5 seconds.

In December 2015 it was announced that the Mission E would become a production car, and now it has been given its own internal codename. Known at Porsche as J1, the car will now enter the long and complex development process, reports Autocar.

Although sharing the same design language as the Porsche 911 and four-seat Panamera, the Mission E will sit on a bespoke platform with a chassis designed to accommodate a lithium ion battery pack, plus front and rear electric motors.

It isn't yet known if the platform could be used for a variety of vehicles, such as an SUV, but if Porsche's first electric car is a success then we would expect a range of different vehicles sharing common components to be developed. This platform is not thought to be related to that being developed by parent company Volkswagen for its range of upcoming electric vehicles, including the Budd-E concept shown off at CES in January.

While electric cars are certainly on Porsche's roadmap, autonomous vehicles are not. Chief executive Oliver Blume said in early February that his customers want to drive their cars themselves, not be driven by an 'iPhone for the road'.