Energy Storage Safety Standards Evolve After High-Profile Incidents
Enhanced battery storage safety standards including updated NFPA 855 and UL 9540A requirements are increasing project costs but building industry credibility for mainstream deployment.
The battery energy storage industry is implementing enhanced safety standards following several high-profile thermal runaway incidents that raised concerns among communities, insurers, and regulators. The evolving safety framework is increasing project costs but also building the credibility needed for mainstream deployment.
The most significant recent incident occurred at a utility-scale BESS facility in California, where a lithium-ion battery fire burned for several days and required evacuation of nearby residents. While no injuries occurred, the incident prompted regulatory reviews and tightened permitting requirements in several states. Similar incidents in Arizona, New York, and South Korea have collectively driven the industry to address safety concerns proactively.
NFPA 855, the Standard for the Installation of Stationary Energy Storage Systems, has been updated with more stringent requirements for fire detection, suppression, ventilation, and spacing between battery containers. Key changes include requirements for thermal runaway propagation testing, enhanced gas detection systems, and minimum setback distances from occupied structures.
UL 9540A, the test method for evaluating thermal runaway fire propagation in battery energy storage systems, has become a de facto requirement for project permitting. Battery manufacturers must demonstrate that their systems can contain thermal runaway to a single cell or module without propagating to adjacent units. Systems that pass UL 9540A testing at the installation level face fewer permitting obstacles.
Insurance is another area of significant evolution. Specialized energy storage insurance products have emerged from carriers including FM Global, Zurich, and Munich Re, but premiums have increased substantially — from $5-$8 per kW-year to $12-$20 per kW-year — reflecting the industry's evolving risk profile. Projects that implement safety features beyond minimum code requirements may qualify for premium discounts.