Audi is set to work with a subsidiary of Chinese solar cell business Hanergy with the aim of producing solar energy to boost the range of electric vehicles.

In an announcement on Wednesday, Audi said that "the first step" of the collaboration would be the integration of California-based Alta Devices' thin film solar cells into a panoramic glass roof. Audi added that, in the future, almost the whole roof would be covered in solar cells.

The idea is that the electricity produced will "flow" into the electrical system of the car, helping to supply its seat heaters or air conditioning system. This would provide a gain in efficiency which would positively impact the vehicle's range, Audi said.

"The range of electric cars plays a decisive role for our customers," Audi Board of Management member for procurement, Bernd Martens, said in a statement. "Together with Hanergy, we plan to install innovative solar technology in our electric cars that will extend their range and is also sustainable," Martens added.

Audi said that, in the future, solar energy could directly charge a car's traction battery. "That would be a milestone along the way to achieving sustainable, emission-free mobility," Martens added.

The solar energy would be produced by thin, flexible solar cells with an efficiency of over 25 percent. Audi said that the cells performed well in high temperature and low light.

The idea of using solar cells on cars is not new. In 2014, Ford unveiled its C-Max Solar Energi Concept vehicle, while later this year the World Solar Challenge will see teams from across the world race solar powered cars 3,000 kilometers across Australia. The Challenge is celebrating its 30th anniversary.