Britain's electricity grid is now balancing supply and demand with the help of a giant battery in Wiltshire funded by Chinese investment.

The 100 megawatt system has been developed by UK company Penso Power with funding from China's state-owned Huaneng Group utility and CNIC Corporation.

Shell, the FTSE 100 oil and gas giant, has a deal to trade all of the power from the battery, which is now fully operational.

Large-scale electricity batteries are set to play a growing role in Britain's electricity grid to help smooth out intermittent supplies from wind and solar power as the country tries to cut carbon emissions.

The battery in Minety can provide electricity for up to 10,000 homes for a day before it needs recharging, Shell said.

David Wells of Shell Energy Europe said: “Flexible storage and supply systems such as Minety have an essential role in balancing supply and demand. We fully support the UK’s target of achieving a net-zero emissions society by 2050. Projects like this will enable that transition.”

Shell is aiming to increase its power business as part of its efforts to adapt to shifts away from fossil fuels and towards electric cars and electric heating.

The battery will be controlled and optimised by its subsidiary Limejump, whose technology helps trade power between generators and batteries.

Shell bought Limejump in 2019 from investors including Statkraft Ventures, Business Angel Co Investment Fund and JamJar Investments, for an undisclosed amount.

Mr Wells said Shell was looking at other battery opportunities across Europe.

“It’s a challenge of what the long-term economics look like. I mean you are very much dependent on grid support to make the economics work at the moment,” he told Bloomberg.