EDF Energy is teaming up with the UK’s largest generator of solar power in a bid to create the biggest challenger brand in the energy retail market by the end of the decade.

The Big Six supplier has thrown its weight behind Sunplug, a consumer energy project developed in partnership with Lightsource, which provides the solar panels on thousands of British roofs.

Sunplug is led by a former Goldman Sachs banker James Brooks, and aims to offer a solar power and battery system at no upfront cost.

Mr Brooks joined Lightsource from his role as head of natural resources at the US bank six months ago to spearhead the project he says could reach one million homes by 2020. This would put the venture ahead of suppliers such as First Utility and Ovo Energy which are currently the largest independents in the market.

“It’s a different way for consumers to interact with their utility,” Mr Brooks said.

The Sunplug system allows energy users to store solar energy through the day and use the power when it’s needed at a fixed price, without the cost of installing or maintaining the panels.