Sungrow and Constantine Energy Storage signing the contracts for the latter’s 825MWh portfolio. Image: Sungrow / Constantine Energy Storage / PR Newswire.

Inverter supplier Sungrow and developer Constantine Energy Storage are partnering on 825MWh of BESS projects in the UK, including two with discharge durations of nearly three hours.

Sungrow Power Supply Co will supply Constantine Energy Storage (CES) with its liquid-cooled grid-scale BESS (battery energy storage system) solution ‘Power Titan’.

The units will go towards an 825MWh pipeline that CES is developing spread across five sites with scheduled commercial operation dates in 2024, through its subsidiary Pelagic Energy Developments. CES will then acquire them once operational.

Two of them, near Birmingham and Chester, will be 57MW/165MWh systems, with a discharge duration of 2.9 hours. Sungrow claimed this makes them the UK’s longest duration grid-scale BESS projects. However, other grid-scale BESS projects which have longer durations but are smaller in scale look to already be online or coming online soon.

Durations are increasing with many new projects opting for two-hours as the market increasingly moves to ‘merchant’ energy trading revenues, as well as Capacity Market contracts, and away from solely relying on grid service contracts.

The UK government is also looking to bring in policy support to foster the growth of the country’s long-duration energy storage (LDES) sector, with many large-scale projects contingent on market reform. The topic was raised at last month’s Energy Storage Summit in London.

“We are delighted and very proud to announce what we think is a game-changing deal for liquid-cooled energy storage in the UK. Constantine Energy Storage is at the very forefront of enabling the energy transition on these shores, and we at Sungrow are happy to assist them in creating a better, cleaner future for everybody. We hope this agreement will be a forerunner for other important deals in the future,” Sungrow senior vice president James Wu said.

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