Developers of Battery Energy Storage Systems (BESS) are urged to engage with the fire and rescue service at the earliest stage of planning, to ensure better understanding of any risks and to help develop strategies and procedures to mitigate these risks.
Fire services are not currently statutory consultees of BESS developments in the UK. However, we are keen to engage with developers to improve the fire safety of the site, and to protect both firefighters and the community.
Below is guidance issued by the National Fire Chiefs Council (NFCC), stating that BESS developers must ensure the risk of fire is minimised by:
- Procuring components and using construction techniques which comply with all relevant legislation.
- Including automatic fire detection systems in the development design.
- Including automatic fire suppression systems in the development design. Various types are available, but we would recommend a water misting system, as fires involving lithium-ion batteries have the potential for thermal runaway. Other systems would be less effective in preventing reignition.
- Including redundancy in the design to provide multiple layers of protection.
- Designing the development to contain and restrict the spread of fire by using fire-resistant materials and having adequate separation between elements of the BESS.
- Ensuring that the BESS is located with due considerations of impact on communities, sites and infrastructure. Prevailing wind directions should be factored into the location of the BESS to minimise the impact of a fire involving lithium-ion batteries, due to the toxic fumes produced.
- Ensuring that the environmental impact includes the prevention of ground contamination, water course pollution and the release of toxic gases.
It is also essential to develop an emergency response plan with DWFRS to minimise the impact of an incident during construction, operation and decommissioning of the facility. This should include:
- details of the hazards associated with lithium-ion batteries;
- how to isolate electrical sources to enable firefighting activities;
- measures to extinguish or cool batteries involved in fire;
- management of toxic or flammable gases to minimise the environmental impact of an incident;
- containment of fire water run-off;
- handling and responsibility for disposal of damaged batteries; and
- establishment of regular on-site training exercises.
The emergency response plan needs to be maintained and regularly reviewed, with any material changes shared with DWFRS.
The BESS facilities should be designed to provide the following:
- Adequate separation between containers.
- Adequate thermal barriers between switch gear and batteries.
- Adequate ventilation or an air conditioning system to control the temperature. Ventilation is important since batteries will continue to generate flammable gas if they are hot. Also, carbon monoxide will be generated until the batteries are completely cooled through to their core.
- A very early warning fire detection system, such as aspirating smoke detection/air sampling.
- Carbon monoxide (CO) detection within the BESS containers.
- Sprinkler protection within BESS containers, which should be designed to adequately contain and extinguish a fire.
- Sufficient water available for manual firefighting – an external fire hydrant should be close to the BESS containers. This water supply should be able to provide a minimum of 1,900 l/min for at least 120 minutes (two hours).
- Further hydrants should be strategically located across the development, and these should be tested and serviced at regular intervals by the operator. If the site is remote from a pressure fed water supply, then an Emergency Water Supply (EWS), meeting the above standard, should be incorporated into the design of the site, e.g. an open water source and/or tank(s). If above-ground EWS tanks are installed, these should include facilities for the fire service to discharge (140/100mm RT outlet) and refill the tank.
Any site design should include a safe access route for fire appliances to manoeuvre within the site (including turning circles). This includes ensuring that any route can accommodate the weight and dimensions of fire appliances, based on the larger measurement of either DWFRS vehicles or the specifications in section five of the Approved Document Part B (Fire Safety)
An alternative access point and approach route should be provided and maintained to enable appliances to approach from an up-wind direction.
As the majority of BESS sites are remotely monitored, consideration should include the fixing of a Premises Information Box at the fire service access point. This should provide an emergency response plan, including details of water supplies for firefighting, and drainage plans highlighting any pollution control devices, penstocks etc.
We are aware that largescale BESS form part of a fairly new technology and, as such, risks may or may not be captured in current guidance in pursuance of the Building Regulations (as amended) and the Regulatory Reform (Fire Safety) Order 2005.
This will highlight challenges fire services have when responding to Building Regulations consultations. For this reason, we strongly recommend applying the National Fire Protection Association (NFPA) 855 Standard for the Installation of Stationary Energy Storage Systems.
You should also follow guidance from the National Fire Chiefs Council around Grid Scale Battery Energy Storage System Planning.