RE: Everyone’s Favourite Climate Solution Has a Fire Problem25 Apr 2021 20:09
“If the percentage of failures holds, that could mean a lot of problems,” said Mike Simpson, senior technical leader at the Electric Power Research Institute. “Even a one-in-10 million likelihood of failure on the assembly line could still lead to many failures on the road.”
Fear of fires isn’t killing global battery demand, which BloombergNEF predicts will grow more than seven-fold by the end of the decade. But the incidents have, at times, shaken public confidence. South Korea, the world’s third-largest battery maker, went on an installation binge of utility-scale batteries until a string of nearly two dozen fires prompted a backlash and government probe. In the end, the investigation blamed many of the fires on sloppy installation and operational errors.
“This is early growing pains for a new technology and a new industry,” said Daniel Kammen, chair of the Energy & Resources Group at the University of California at Berkeley. “We didn’t even have grid-scale batteries a few years ago.”
Some fires can be traced to manufacturing defects in the battery cells themselves, or physical damage after installation. Overcharging can also be a problem, Simpson said, as can poor integration with other electrical systems.
Each of those factors can tip a battery cell into a dangerous, uncontrolled chain reaction known as thermal runaway. The flammable electrolyte inside the cell suddenly heats up and causes the same thing to happen in adjacent cells. Once ignited, the batteries can emit toxic fumes.
Firefighters are learning on the fly how to respond. Dousing the flames takes a large amount of water, and cells can re-ignite hours after the initial fire has been extinguished. Following the explosion last year at the Arizona energy storage facility, investigators spent months carefully removing racks of batteries so they could be drained of energy.
Brian O’Connor, an engineer with the National Fire Protection Association, said first responders need far more training on how to handle burning batteries. The association, which develops fire codes, recently issued standards for energy storage installations in buildings, including how far they should be spaced apart and which fire suppression systems to use. “The technologies do not come without risks,” O’Connor said.
At a recent conference, the fire association hosted several sessions on the safety of battery installations. One was titled, “Energy Storage in Your Home: Can You Sleep at Night?”
South Korea showed what can happen when battery fires cause alarm. A booming market that had seen more than 4 gigawatt-hours of capacity added in 2018 suddenly froze up. Installations in South Korea last year could have fallen 75 percent or more, according to preliminary BNEF estimates.
Government investigators did not blame the fires on any inherent flaw in the batteries themselves. Instead, they faulted the design and operation of energy storage systems that included the batteries.