London's Hounslow council has installed 6,000 solar panels on a wholesale market rooftop, which it says makes it the largest such array put up by a local authority.
The London Borough said the £2m project, which used the roof of Western International Market, is also the first by a council to adopt battery storage to maximise the power from the panels.
It uses 6,069 panels in total, generates 1.73 megawatts (MW) and stores some of its energy in four 60kW lithium batteries. The system now generates approximately half the site's required electricity.
The site is west London's largest wholesale market for fresh produce and flowers and uses around 3.5 megawatt hours (MWh) of electricity to provide climate-controlled facilities to around 80 wholesalers and buyers, the equivalent of powering 1,750 homes a year.
Hounslow council, which owns the market near Heathrow Airport, says the solar system will contribute two per cent of its carbon reduction target, cutting emissions by more than 780 tonnes a year.
The project is set to save the council £148,000 in energy costs which, along with £100,000 in generation tariff payments and £7,000 export tariffs, means that the council expects to be £255,000 better off in the first year of operation.
Charles Pipe, energy manager at Hounslow, said: "From the very beginning, this project has been about reducing our carbon footprint and making an investment for the future.
"But we have achieved so much more than that. Not only can we expect to see immediate savings on our electricity bills, but we are expecting to see a return on this investment in about five years."
LG Electronics, one of Hounslow's partners in the scheme, said it was the company's largest solar panel installation in Europe and would deliver significant costs savings to the borough.
Bob Mills, LG Solar's UK senior solar sales manager, said: "The project has set the wheels in motion for further investment and research into the potential of battery storage, which is set to revolutionise the solar industry."
In March 13,860 solar panels were installed on the roof of a massive logistics site in Telford to make one of the largest rooftop solar plants in the UK.