A London council is unveiling a vast installation of 6,000 solar panels on a wholesale market rooftop, which it says is the largest such array put up by a local authority.

The London Borough of Hounslow says its £2m investment in solar, which has been installed on the roof of Western International Market, is also the first by a council to adopt battery storage to maximise the power from the panels.

The 1.73 megawatt (MW) array of 6,069 panels and four 60kW lithium batteries system now generates 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 1,750 homes a year.

Hounslow council, which owns the market near Heathrow Airport, says the solar system will contribute 2% of its carbon reduction target, cutting emissions by more than 780 tonnes a year.

It will also save £148,000 in energy costs which, along with £100,000 in generation tariff payments and £7,000 in 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.

LG Solar’s UK senior solar sales manager Bob Mills said: “What’s more, 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.”