InterGen: Battery energy storage

The ongoing growth and integration of renewable energy sources, such as solar and wind, is essential in the UK’s transition to net zero by 2050. However, these energy sources are intermittent, generating power when the sun shines or the wind blows which may not be when power is required by the grid. Large-scale batteries can help mitigate this challenge and increase the cost-effectiveness and flexibility of renewable energy, with Great Britain’s Electricity System Operator projecting up to 50 GW of electricity storage technologies by 2050.

InterGen, which currently supplies around 5% of the UK’s power generating capacity, has been granted consent by the UK’s Department for Business, Energy and Industrial Strategy for a battery energy storage project as part of their Gateway Energy Centre development on the banks of the river Thames in Essex.

The £300 million project is expected to have an initial capacity of 320 MW / 640 MWh, expanding to 450 MW / 900 MWh.

When complete, the 450 MW / 900 MWh battery energy storage could supply approximately 227,000 homes per year, or fully charge up to approximately 16,100 electric vehicles. However, it will mostly be used to support and stabilise the electricity supply by providing fast-reacting power and system balancing.

Ramboll has been an integral partner to InterGen in securing the government consent for the project, which required in depth knowledge and understanding of the evolving UK regulations and government guidance for these new large-scale battery energy storage projects.

Securing renewable energy

At the time of the consent, the project was more than ten times larger than UK’s then largest operational battery energy storage project, representing a significant piece of system architecture in the UK’s transition to net zero. Great Britain has already cut its carbon emissions by 44% since 1990, marking, according to the Economist, the fastest decarbonisation rate of any rich country.

Additionally, InterGen is progressing a second battery energy storage project as part of their Spalding Energy Park development in Lincolnshire. This project is expected to have an ultimate capacity of 550 MW / 1100 MWh.

Ramboll has supported InterGen on both the Gateway Energy Centre and Spalding Energy Park developments since their inception, providing engineering and environmental consultancy services, including pre-feasibility and feasibility studies, environmental impact assessments and environmental permitting.

In February 2022, InterGen secured a T-4 Capacity Market award for the battery energy storage, which ensures the security of electricity supply for the UK. In early 2023, InterGen anticipates the completion of funding and procurement for the construction of this first-of-a-kind project to support a 1 October 2025 operational date.

Further, InterGen has plans for Phase 2 of the battery energy storage project, expected later this decade, which would more than double the capacity from 450 MW to 1 GW.