Fire risks in Battery Energy Storage Systems (BESS): How a comprehensive risk management strategy can enhance safety

Understanding the fire risks

Currently, lithium-ion batteries are at the heart of BESS installations and are integral to their performance. However, this technology introduces a fire hazard that project owners’ need to be aware of. Because of their chemical composition, these batteries can be highly reactive when exposed to certain conditions. When thermal runaway (a process where a battery cell's temperature increases uncontrollably) occurs, it can spread from one cell to another, causing cascading failures and posing safety risks to the entire BESS facility.

Fire prevention risk management hierarchy

To address these risks, a multi-layered approach to fire prevention is essential.
Relying on specialised consulting, engineering and quality control services is essential in ensuring that fire safety measures are up to standard and that BESS installations are designed to mitigate these risks effectively.

1. Safer chemistries: One of the most promising developments in reducing fire risks is the adoption of safer battery chemistries. Lithium iron phosphate (LFP) batteries have gained preference over nickel manganese cobalt (NMC) cells, thanks to their improved stability and lower risk of thermal runaway. LFP batteries are less prone to overheating and more resistant to fire, offering a safer alternative for large-scale energy storage projects.

2. Large-scale fire testing (LSFT): Manufacturers are taking a proactive approach to fire safety in Battery Energy Storage Systems (BESS) by conducting large-scale fire testing (LSFT). While there is no current standard or regulation mandating these tests, LSFT is proving invaluable in understanding how a full-scale BESS fire might unfold. These insights help refine fire prevention technologies, enhance system safety, and inform site design, fire response plans, and overall risk management. Certification bodies assess LSFT results to ensure compliance with existing fire safety regulations, reinforcing trust in BESS as a reliable and secure energy solution.

3. Engineering controls: Engineering controls are essential in preventing fire escalation in BESS installations. Key components include:

• Battery management systems (BMS): These systems monitor battery performance, temperature, and voltage, ensuring that the cells are operating within safe parameters. In the event of irregularities, the BMS can shut down individual cells or entire modules to prevent further risk.
• Cooling mechanisms: Effective cooling systems are critical in maintaining safe operating temperatures, especially in large-scale energy storage facilities. Advanced thermal management technologies can prevent overheating and reduce the likelihood of a fire incident.
• Fire suppression systems: Automated fire suppression systems, such as clean agent systems or water mist systems, are designed to extinguish fires quickly before they can spread.

4. Site design: Proper site design is crucial in preventing fire escalation and ensuring an effective emergency response. This includes:

• Adequate spacing: Ensuring sufficient space between battery racks and other equipment is essential for fire safety in Battery Energy Storage Systems (BESS). Proper spacing not only allows for ventilation to reduce heat buildup but also helps limit fire spread and heat transfer between units. Additionally, it provides crucial access for fire responders, enabling them to move safely and effectively around the site to manage and contain fires. Thoughtful site design with adequate spacing enhances overall safety and risk management in BESS installations.
• Protective barriers: Fire-resistant barriers or enclosures can prevent the spread of fire between units and protect the surrounding infrastructure.
• Fire-resistant materials: The use of fire-resistant materials in the construction of storage areas helps limit the impact of a fire should one occur.

5. Administrative controls: Along with physical and engineering controls, administrative controls are essential in ensuring that fire risks are effectively managed. Developing fire management policies and collaborating with local authorities can help create tailored responses in the event of a fire. This includes establishing evacuation plans, training staff in fire response procedures, and ensuring compliance with local fire safety regulations.

The role of inspection and certification

When it comes to fire safety for BESS projects, a comprehensive risk management strategy is essential. Independent and specialised technical advisors such as Enertis Applus+ play a crucial role in ensuring that BESS installations meet stringent safety standards. Through highly specialised BESS consulting, engineering and quality control services, we help clients ensure the reliability and optimal design of stand-alone and hybrid battery energy storage systems from design to operation.

Our experts assist in:

• Conducting site assessments to identify fire risks and recommend mitigation strategies.
• Providing engineering design, with conceptual and basic engineering design for BESS project development, as well as detailed engineering during pre-construction/construction.
• Providing ongoing inspections to ensure that safety measures remain effective throughout the operational life of the system.

Conclusion

Fire risks in BESS projects are a significant concern, but with the right preventive measures and the expertise of specialised technical advisors, these risks can be mitigated.

If you're looking to strengthen your BESS fire safety strategy, get in touch with our team of experts today.

About the author:

Angus Moodie is Engineering Manager for the UK & Northern Europe at Enertis Applus+, a provider of technical consulting, engineering and quality control services in the renewable energy and energy storage sector. Angus has experience in product and system design, including renewable and energy storage systems, and power systems and is a chartered member of the Institution of Engineering and Technology (IET).

References:

1. Fire Risks in Lithium-Ion Batteries and Thermal Runaway: J. J. Lee et al. (2019). "Thermal runaway characteristics of lithium-ion batteries" - ScienceDirect
2. National Fire Protection Association (NFPA) - NFPA 855: Standard for the Installation of Energy Storage Systems
3. Safer Battery Chemistries (LFP vs. NMC): "Comparing lithium iron phosphate and nickel manganese cobalt batteries: A case for the LFP battery" - Battery University
4. T. Y. Kwon et al. (2021). "Safety of Lithium-Ion Batteries" - Frontiers in Energy Research
5. Large-Scale Fire Testing (LSFT) and Fire Prevention Technologies: UL 9540A Standard: "Fire Test Method for Energy Storage Systems and Equipment"
6. S. Liu et al. (2020). "The progress of fire safety technology for energy storage systems" - Energy Storage Materials
7. Engineering Controls and Site Design: "Fire Safety for Energy Storage Systems" - National Fire Protection Association (NFPA) Journal
8. "Energy Storage Systems Design and Safety" - International Fire Protection
9. Administrative Controls and Local Regulations: "Energy Storage Safety Guidelines" - U.S. Department of Energy (DOE) "Fire Prevention and Safety for Energy Storage Systems" - International Electrotechnical Commission (IEC)
10. “Effective battery storage fire safety involves going beyond standards” - Angus Moodie, Engineering Manager UK & Northern Europe, Enertis Applus+. Cited from www.energy-storage.news on February 18, 2025.