Battery energy storage systems (BESS)

Battery energy storage systems (BESSs) use batteries, for example lithium-ion batteries, to store electricity at times when supply is higher than demand. They can then later release electricity when it is needed. BESSs are therefore important for “the replacement of fossil fuels with renewable energy”.

The government has a legally binding target to reduce the UK’s greenhouse gas emissions by 100% by 2050, compared with 1990 levels. This is known as the ‘net zero target’. To meet this target, the government has set the aim of achieving “clean power by 2030”. This means “being on track to achieving at least 95% of low carbon generation by 2030”.

Renewables, such as wind and solar power, rely on the weather to generate electricity. This means that they cannot adjust to demand from consumers as easily as fossil fuels and nuclear power can. Therefore a decarbonised power system will need to be supported by technologies that can respond to fluctuations in supply and demand, including energy storage.

The government’s Clean Power Action Plan stated that it expected 23–27 GW of battery storage to be needed by 2030 to support clean power, up from 4.5 GW in 2024.

What permissions do BESSs need?

Installing a grid-scale BESS requires planning consent. Planning is a devolved matter, and decision-making rules differ across the UK.

In England and Wales, decisions on BESSs (regardless of their capacity) are made by local planning authorities. In Scotland and Northern Ireland, BESSs require consent from either ministers or the planning authority depending on their storage capacity.

Depending on its capacity, a BESS may also require a generating licence to operate. Generating licences are issued by Ofgem in Great Britain or by the Utility Regulator in Northern Ireland.

Concerns about the safety of BESSs

Although safety incidents for BESSs are rare, a common concern about BESSs is the potential fire risk of lithium-ion batteries (PDF). Lithium-ion batteries can catch fire because of a process called “thermal runaway”. It can occur, for example, if part of a battery is damaged.

Understanding of thermal runaway has improved in recent years, leading to more flame-resistant batteries. BESS sites can be also designed with safety features, such as fire suppression systems.

There is no reliable, publicly accessible record of the number of BESS fires that have occurred in the UK or elsewhere. Two documented incidents of a BESS fire in the UK include: a fire at a BESS site in Liverpool in September 2020 (PDF) and a fire at a BESS project under construction in Essex in February 2025.

How is the safety of BESSs regulated?

While there is no single piece of legislation that sets specific requirements for BESS sites, there is a framework of relevant legislation that applies. Individual batteries may have to adhere to product safety regulations (for example if second-life batteries are used) and grid-scale facilities will also have to comply with relevant fire safety requirements and health and safety laws. The Health and Safety Executive has a grid-scale battery energy storage systems webpage that collates relevant existing legislation. The government also published new guidance on the health and safety of grid scale electrical energy storage in April 2024.

There are concerns that existing regulations and guidance are not sufficient to address the safety risks posed by BESSs. For example, there are calls for fire and rescue services to be made statutory consultees in planning applications for BESSs.

In response to concerns about the safety of BESSs, the government said BESSs were covered by “a robust regulatory framework”. It published guidance in August 2023 which encourages developers and local planning authorities in England to consult their local fire and rescue service in preparing and deciding on planning applications for BESSs.

Barriers to the development of BESSs

The Commons Business and Trade Select Committee has raised concerns that the UK has “insufficient domestic manufacturing capacity” for batteries, and the Commons Foreign Affairs Select Committee has raised concerns that “the UK is almost completely dependent on imports for critical minerals”, such as lithium, that are used in batteries.

The government set out how it intends to secure the UK’s battery supply chain and improve the resilience of the UK’s critical minerals supply in its UK battery strategy (November 2023) and critical minerals strategy (July 2022). The Labour Government has said it plans to produce a new critical minerals strategy in 2025.

Barriers to the development of BESSs and other energy storage systems also include high upfront capital costs, uncertain revenue streams and delays to grid connections.

The government and Ofgem are implementing a new ‘cap and floor’ revenue support scheme for long duration electricity storage (LDES), which will include BESSs as well as other technologies. This will provide a guaranteed minimum revenue stream (the floor) and a limit on revenues (the cap) for long duration energy storage. Ofgem aims to approve the first round of projects by Q2 2026.