Battery energy storage projects are increasingly in the limelight over fires, including the Moss Landing fire and at a data center used by Elon Musk’s X, both of which happened this year. But how valid are the concerns?

The stats: Just 28 thermal accidents have taken place at battery energy storage system (BESS) projects between the US and Canada since 2012. While headline-grabbing, considering how many hours batteries have operated to date across North America, the actual accident rate is very low.

Incident rates are comparable to nuclear power plants, themselves very safe, and lower than aviation accidents. Engineers continue to develop safer and more resilient systems.

Improving designs:

• Battery chemistries are shifting to types that are less prone to thermal runaway. The top-performing lithium-ion batteries have typically been nickel-magnesium-cobalt (NMC) chemistries for their cathodes, but developers are increasingly using lithium-iron-phosphate (LFP).
• Management systems are improving every year and can better detect overheating, overcharging and short circuits.
• Modular designs of batteries, now often inside shipping containers, prevent fires from spreading by isolating the event.

Despite a strong safety record, headlines have prompted many cities to outright ban their use.

Read the full report: Burning Questions: Unpacking the facts around battery storage fires