EDF is selling three power grids and a private power network business in the UK to Hong Kong-based billionaire Li Ka-Shing for £5.8bn ($9.1bn).

The acquisition has been made by the Hong Kong tycoon’s investment vehicles, Cheung Kong Infrastructure and Hongkong Electric, from the French company.

EDF’s electricity distribution networks supply power from the high-voltage grid to 20 million people via three adjacent networks in London and England’s east and southeast.

The private networks business supplies power under ten year-long contracts to the London Underground, Heathrow airport and the Channel Tunnel.

The acquisition will increase Cheung Kong Infrastructure’s presence in the UK and will cut the debt of EDF, according to Reuters.