Atlantic Green has selected Ameresco and Envision Energy for the construction of a 300MW/624 mega watt hours (MWh) battery energy storage systems (BESS) project in the UK.

Called Cellarhead, the project is poised to enhance the UK's energy security and reliability by connecting to the National Grid's Cellarhead sub-station in the West Midlands region of England.

The start of construction at the site is expected within this year, with the project's connection to the electricity grid projected for the end of 2026.

Ameresco has been awarded a contract for engineering, procurement, and construction (EPC) as well as operations and maintenance, which includes battery supply and balance of plant services.

The EPC contract is valued at about $249m (£196.5m).

Envision Energy will supply the BESS and associated services, along with equipment warranties.

The Cellarhead BESS project, with its maximum energy capacity of 624MWh, aligns with the UK's net-zero ambitions by supporting the integration of clean energy generation, reducing dependence on fossil fuels, and aiming to lower greenhouse gas emissions.

Upon completion, Atlantic Green will retain ownership and operation of the BESS, utilising it as an energy storage asset.

Atlantic Green managing director Nick Bradford said: “We believe that a continuous development of battery energy storage is a vital step in the UK’s journey to achieving net-zero carbon emissions, and we are excited to team up with Ameresco to bring this vision to life.

“Since our founding, Atlantic Green has consistently prioritized finding strategic ways to leverage our battery storage assets with the wider community and we are eager to answer the rising demand for battery storage with this new project with such a level of energy capacity, to really make the impact on the UK electricity system that is much needed.”

Ameresco UK operations senior vice president Mark Apsey said: “We’re excited to announce our collaboration with Atlantic Green to construct one of the largest battery energy storage projects in the United Kingdom.

“Energy storage is one of the key technologies required to achieve the UK’s net zero targets. Atlantic Green’s strong company leadership and robust track record of developing similar projects makes them an excellent partner in this endeavour.

“Together, Ameresco and Atlantic Green will help support the UK’s progress towards increased power autonomy and achieving net-zero carbon emissions by 2050.”

In November 2023, Ameresco was chosen by Silicon Valley Power to construct a 50MW/200MWh BESS project in Santa Clara, California.

Known as the Kifer Energy Storage project, this project will contribute to local capacity and provide a more reliable and flexible electrical system.