The growing threat of battery storage fires

The devastating Moss Landing Power Plant fire in California was global news and fed into concerns over the safety of Battery Energy Storage Systems (BESS). The January 16^th blaze destroyed a 300-megawatt energy storage facility near Santa Cruz, causing widespread damage and the evacuation of 1,500 local residents. With over 100,000 lithium-ion batteries housed within the facility, the blaze has once again highlighted the potential risks associated with the proliferation of energy storage technologies writes Thomas Roche, Secretary of Business Sprinkler Alliance.

At this point it is worth pointing out that the Moss Landing facility is different to much of the grid scale schemes being discussed in the UK. The Moss Landing facility was an existing power generation building into which the BESS had been installed, effectively turning the building into one large container with the battery systems inside. In contrast, the grid scale installations that are hitting the news due to planning objections in the UK are primarily containerised units, shipping container sized enclosures within which the BESS is located. These units sit in the open in a configuration with ancillary equipment between several containerised units to form a larger BESS installation.

These energy storage systems are becoming key to achieving greener, renewable energy by supporting electrical generation from renewable sources. A government report on UK battery strategy¹ estimates that BESS could provide 10-20GW of capacity to the UK grid by 2030, and 30-35GW by 2050. It should be no surprise that our demand for batteries continues to grow with the global lithium-ion battery market surging towards a projected $176.75 billion by 2032².

As these containerised BESS systems have become operational, fire incidents and explosions have occurred which have drawn international attention. In February, a fire that broke out at a 300-megawatt BESS facility, under construction in Tilbury in Essex, is another call for heightened scrutiny of the safety implications of these facilities. This has led advocates for fire safety to call for more stringent regulations requiring these facilities to be built in defined areas, with good separation between units, fire protection and good access for firefighting. These measures would minimise the risk of widespread harm in the event of a catastrophic failure.

Regardless of the installation, by now, most people have heard of lithium-ion batteries and the accounts of fires involving them from scooters and bikes, to vehicles and then these BESS units. Despite these concerns, lithium-ion batteries are widely considered safe when used, operated and stored correctly. The hazards arise when they are damaged or fail, moving into thermal runaway, an uncontrolled chemical reaction that can lead to fires and the gases generated potentially being explosive. It is the latter element that is rarely understood but should be when we talk of such BESS within enclosures.

Significant efforts are being made to improve product testing standards and raise consumer awareness to help address fire safety risk related to lithium-ion battery powered items around the home, and to some extent vehicles. The fire safety guidance for grid-scale BESS or even smaller scale BESS within residential premises is only slowly emerging. The UK Government recently confirming that such grid-scale BESS are regulated by the HSE through a combination of existing regulations being applied to such devices ranging from the Health and Safety at Work Act to DSEAR ³.

With the rapid growth of BESS installations, it feels as though we are playing catch-up on the fire risks. Those involved in this space have witnessed objections to the planning for these grid-scale BESS, with local campaigns. In the UK, for example, plans to build a 1,000-megawatt BESS in rural Yorkshire have been met with significant opposition. Local campaigners warn that the risk of fire is high, citing the 70 fires that have occurred at battery storage facilities worldwide between 2018 and 2023.

An outcome of these campaigns are private member Bills going through the House of Commons and the House of Lords that are looking to address these issues. Regarding BESS, the latter Bill⁴ is looking to make the Fire and Rescue Services a statutory consultee for planning applications for such systems as a common issue arising from the remote location of the installations are attendance time, access and water for firefighting.

Whilst most of the proposed elements are meaningful, some need to be addressed to ensure all involved understand the potential issues. The nature of battery fires is such that stopping them is very difficult. The current approach to limiting these fires in containerised BESS units generally involves holding the blaze within the structure where it originates. As they are in the open, if there is an explosion potential then we can warn people to be clear and vent any explosion safely. The expectation is that the equipment within the originating structure will be lost to the fire, irrespective of the fire protection used, due to the nature of such incidents. The fire protection measures are designed to limit propagation to the next structure and surrounding containers and to help control the fire, but may not stop it in its tracks. This is an item that is commonly misunderstood.

While this strategy may help protect surrounding buildings and equipment, it has significant implications for such events. Fires in these enclosures can take hours or even days to extinguish, and the extensive use of firefighting resources only increases the challenge. The Moss Landing fire, for example, became the largest battery storage plant fire in the USA, requiring weeks of intervention before it was brought under control. It was reported that flare-ups continued a month after the fire was brought under control. The aftermath of an event on this scale extends beyond the fire itself with environmental fall-out from the fire expected to be significant.

Unified approach and a warning

There is little doubt that battery energy storage systems are here to stay and will play a pivotal role in the global transition to cleaner energy. However, it is critical that we recognise the fire hazards they present and take steps to mitigate these risks. As the number of these facilities continues to grow and their reliance on lithium-ion batteries shows no sign of abating, it’s essential that authorities around the world develop and implement consistent guidelines and standards for their construction, operation, and fire safety.

However, we must always consider the context in which these systems are being placed. We may have options for a controlled burn out of a unit when it is sitting in the open however the dynamics change when these BESS units are brought into a building structure. The rooms that we build for power units today will be ideal for the fire hazard, but they are often landlocked and therefore present extreme challenge when considering the potential for explosions.

Energy storage is critical for a sustainable future, but we must ensure that its implementation does not come at the cost of public safety and we must stay alert to how and where they are being used.

¹ https://www.gov.uk/government/publications/uk-battery-strategy/uk-battery-strategy-html-version

²The "Lithium-ion Battery Market, Size, Global Forecast 2024-2028, Industry Trends, Share, Growth, Insight, Impact of Inflation, Company Analysis"

³ The Dangerous Substances and Explosive Atmospheres Regulations 2002

⁴ Lithium-Ion Battery Safety Bill - https://bills.parliament.uk/bills/3742

Photo Credit: The fire at Vistra Energy’s Moss Landing battery storage facility on Jan. 16, 2025. The image by Guy Churchward is licensed under CC BY 2.0