By Derrick Hall, Director of Sales & Marketing at Kentec Electronics Ltd and Nick Bartlett, principal engineer and founder of fire protection engineering and consulting firm, ATAR Fire
Battery energy storage solutions (BESS) are an integral part of the world’s sustainability shift, but their inherent fire risk presents developers with a huge challenge.
Because while BESS facilities are being built at pace, the regulations are not keeping up.
Instead, the industry faces a complex jigsaw of rules, recommendations, and best practice across jurisdictions.
We believe that standardised, whole-system certification is the only way to unlock the potential of this emerging market – and to keep people and investments safe.
Challenges and opportunities
The BESS market is expanding at rapidly.
Currently valued at around $7.8 billion globally, the industry is forecast to grow at a compound annual growth rate (CAGR) of 26.9% over the coming years.
The main reason is sustainability.
Renewable energy sources, such as solar and wind, can be intermittent, and BESS provides a way to store power for use when the sun is not shining and the wind is not blowing.
At the same time, energy security has become a major concern, leading to energy-intensive operations, such as data centres, to adopting BESS technology for backup power during shortages or supply interruptions.
Another driving force is the emerging energy arbitrage market, in which companies purchase electricity during low-cost periods, store it in BESS systems, and sell it back to the grid when prices rise.
The scale of the opportunity, however, is matched by the scale of the fire safety challenge.
Facilities store energy in lithium-ion batteries, which are highly sensitive to temperature and inherently flammable.
When a battery produces more heat than it can safely disperse, it can enter thermal runaway, a chain reaction that causes temperatures to rise uncontrollably.
Overcharging or system faults can cause the release of flammable gases such as hydrogen.
As they accumulate within a BESS module, they can trigger explosions that emit toxic fumes and hazardous materials.
Prolonged exposure to high heat also accelerates battery degradation, further increasing the likelihood of failure.
With a single BESS installation containing hundreds or even thousands of lithium-ion batteries, a fire that starts in one cell can quickly spread throughout the entire system.
And once they start, these fires are notoriously difficult to control.
Fragmented landscape
The frameworks governing the safe installation and operation of BESS facilities are still catching up with their rapid development, and, across the industry, perceptions of safety and best practice vary widely.
Regulators, consultants, and insurance companies often interpret requirements differently, resulting in a patchwork of approaches that breeds uncertainty.
From product design to installation and operation, everyone appears to have a different perception of safety, and of what is required to protect it.
This has led to hesitation and, in some cases, questionable operational philosophies, including the so-called “let it burn” approach.
The reasoning was straightforward but stark.
Fires that break out in high-voltage containerised battery systems are highly unpredictable.
The safest course for emergency responders, then, may simply be to stand back and allow them to burn themselves out.
Yet while life safety must always come first, “let it burn” not only leaves high value assets in ruins, it also runs counter to the ethos of fire prevention and protection.
Change is starting to happen, but we are not yet there yet.
Thanks to advances in detection, suppression, and explosion-mitigation technologies , we are now seeing far more emphasis on integrated detection and control systems that move the model from containment to prevention.
Yet with every jurisdiction still approaching BESS safety differently, there remains room for confusion.
In the United States, for example, NFPA 855, defines installation requirements for stationary energy storage systems.
UL 9540 and UL 9540A address BESS system certification and thermal runaway and fire propagation characteristics, while UL 2075 governs hydrogen and gas detection.
Each standard serves a specific purpose, but bringing them together into a coherent framework remains a work in progress.
What’s more, even where certification does exist, it can mask inconsistencies.
A system carrying a UL 9540 listing, for instance, is not always verified down to its individual components.
In some cases, testing laboratories perform construction reviews without confirming that every fan, vent, or sensor is independently listed.
As such, a certified container may well be built from unlisted parts.
The same applies to safety systems.
Deflagration vents or extraction fans may be noted in certification documents, but their actual performance and compliance with performance standards such as NFPA 68 or NFPA 69 may never have been validated.
Without tighter oversight, quality can vary significantly between manufacturers and testing laboratories.
The global nature of the BESS market compounds the challenge.
Products are often designed and manufactured in one country and sold across many others.
Greater standardisation has the potential to close these gaps.
A universal framework combining NFPA 855 with UL 9540, UL 9540A, and UL 2075 would streamline expectations, raise the quality baseline for manufacturers, and simplify approval processes for new projects.
NFPA 855 is already gaining traction as an internationally recognised reference standard, but there is still much work to be done.
Another area ripe for improvement is system compatibility.
Under current UL 9540 rules, fire panels and detectors are not typically evaluated for compatibility, even though they must operate as a unified safety system.
Outside of BESS applications, US codes such as the International Fire Code already mandate compatibility, but this principle has not been integrated into energy-storage standards.
The presence of battery management systems, which play a key role in mitigating potential incidents, and their overall integration with other systems, remains inconsistent.
Proactive action
Some manufacturers are proactively bridging the compliance gaps by ensuring all components of their safety solutions are UL-listed.
This whole-system approach represents best practice, even if it’s not yet mandatory.
Kentec, for example, has taken a whole-system certification approach, by ensuring its panels, detectors, and ancillary devices are UL-listed together.
Their integrated BESS fire preventative solution includes a UL 864-approved panel, UL 268-approved smoke detector, and the K-Detect-iON hydrogen sensor, which carries UL 2074 and UL 2075 listings referenced against the panel
K-Detect-iON remains the only UL 2075-listed, calibration-free hydrogen sensor developed specifically for BESS applications, requiring no recalibration for at least 10 years.
And its UL 2075 approval offers authorities having jurisdiction (AHJs) and contractors clear evidence of component-level compliance.
It integrates seamlessly with Kentec’s Sigma extinguishant panels, which also meet leading global standards, including EN 54 Parts 2 and 4, EN 12094 Part 1, UL 864 (10th Edition – imminent release following extensive field trials) [Pending UL approval]*, FM Standards, and NFPA 855 Energy Storage Protection.
The offering positions Kentec’s solution as a benchmark for standardised, compliant BESS safety design.
The road ahead
As BESS deployments continue to expand, we need to acknowledge that properly certified, fully compatible systems are not just safer, but also more commercially viable.
Building aligned global standards is essential, and will require collaboration between manufacturers, consultants, code developers, and enforcement authorities, alike.
That won’t happen over night.
But for now, taking a comprehensive approach to compliance, ensuring every component in a system is UL-listed and tested as part of an integrated whole, is the best practice benchmark for risk mitigation, and for future-proof BESS.