This is the third part of a series examining the McMicken
battery fire of 2019 and its ramifications for the energy storage
industry. This installment addresses the lessons for fighting fires
at battery facilities. Part I covered how battery developers have
enhanced fire safety�in battery plant designs since last year,
and Part II tackled the quest to
identify the root cause of the incident.
The 2019 lithium-ion battery fire in Surprise, Arizona warned
the world of the dangers new grid infrastructure can pose to
The emergency response plan provided to local firefighters
lacked crucial details about the threat they were facing. And the
young energy storage industry had never experienced what was about
to happen: a gaseous explosion so powerful that it flung responders
dozens of feet through the air.
The mere knowledge that this is possible changes the risk
profile of grid batteries; as long as firefighters know what
happened in Arizona, theyâ€™ll be able to approach future incidents
with a greater level of caution.
Battery developers have already
improved their safety designs in the hopes of preventing a
repeat of the McMicken disaster, which sent four first responders
to the hospital. But an
investigation by Underwriters Laboratoriesâ€™ Firefighter
Safety Research Institute could spur a similar upgrade in the
approaches first responders use when dealing with grid battery
facilities â€” and in how battery developers deal with first
â€œNobody wants batteries to stop â€” we know we need the
technology, the communities need them to move the world forward,â€
said Stephen Kerber, director of FSRI and co-author of the report.
â€œBut I think we can find a compromise of safety and getting fire
The specter of the McMicken explosion has canceled battery
development in at least a few different cases, as local residents
and fire chiefs worried they would be ill-equipped to handle
similar conflagrations. Proactive outreach to local firefighters
has become crucial to the success of new battery projects.
Plenty of other projects show that it is possible for battery
developers to meet the safety needs of local communities, and even
leave them better off. Batteries are expected to play an
increasingly pivotal role in complementing renewable power in a
low-carbon grid. But that will only happen if developers earn and
maintain the trust of firefighters around the country.
What went wrong in Arizona
The report, released in July, paints a picture of responders
doing their best to operate in an information vacuum.
Laboratory chemists know what happens when lithium-ion batteries
enter â€œthermal runaway,â€ in which one cell overheating ignites
a neighboring cell until a whole rack burns up. And battery experts
had found that this emits gases which, if trapped in a confined
space and exposed to the right mix of heat and oxygen, can
But high-level battery science was not in the toolkit of the
firefighters dispatched to a call about smoke emanating from an
Arizona Public Service facility outside of Phoenix. Even the hazmat
technician curriculum did not include basic energy storage-related
hazards, the report found.
Nor did it advise on what to do about the foul-smelling,
low-lying white vapor cloud emanating from the container.
â€œThey had just about every hazmat expert in the entire Phoenix
region on the phone trying to figure out what to do about this,â€
Kerber told GTM. â€œThe emergency response plan didnâ€™t really
cover thermal runaway, so there was no playbook.â€
The fire department had meters to detect for typical gas leaks,
so they cleared out a 300-foot perimeter and measured with what
sensors they had. They noticed high levels of carbon monoxide and
hydrogen cyanide at the scene.
But the crew did not have sensors that would pick up the
concentration of explosive gases building up inside the container.
Doing so typically requires a larger piece of equipment rather than
a handheld device, Kerber said. The battery facility also lacked
such a meter, and even if it had one, the communications feed cut
out after things started going wrong.
â€œThe fire service is there to stabilize the incident,â€
Kerber said. â€œThey want to be able to mitigate it and turn it
back over to the building owner.â€
That desire to stabilize the incident drove the decision to open
the door to the container. The vapor cloud had diminished, and the
measurable hot zone in the enclosure seems to be getting smaller,
too. Four people went in to open the door, collect additional
readings, and gauge whether the situation posed an ongoing
Even after the door opened, things seemed fine. The firefighters
saw no signs of active fire and took measurements for about three
minutes before the explosive release of pressure known as a
deflagration event. The blast threw one man 73 feet through a chain
link fence, dislodged the teamâ€™s helmets and masks, and left all
â€œAt the end of the day, the fire department owns the decision
to act,â€ Kerber said. But, he added, â€œAll the way up until the
deflagration itself, the mindset was things were getting better,
the incident was stabilizing.â€
Spreading knowledge across a fragmented fire service
Safety codes have evolved since the McMicken system was built,
and the electricity industry and firefighters now have access to a
wealth of information that the responders in Arizona did not. But
one risk is that the lessons do not disseminate evenly among the
nearly 30,000 fire departments across the U.S.
â€œThe fire service in the United States is very fragmented,â€
Kerber said. â€œThereâ€™s no one mechanism to reach them
Grid batteries are still a relatively new phenomenon, with
installations clustered in a few states. But annual installations
are expected to be
seven times larger in 2021 than they were in 2019, and that
influx will bring batteries to new places. Urban areas like Phoenix
may have well-resourced fire departments with dedicated hazardous
materials teams. But rural areas with smaller staffs and budgets
have to determine their own comfort level with lithium-ion
batteries. And the explosion in Arizona already changed some
A 140-megawatt battery development in Valley Center, north of
San Diego, failed to win local permitting approval in July after
community members objected to the perceived threat.
â€œJust last year there was an explosion in Arizona that injured
four firefighters and resulted in Arizona Public Service shutting
down two other facilities,â€ one resident testified at the
planning meeting, according to local newspaper
Valley Roadrunner. The developerâ€™s insistence that any fires
would be contained at the module- and container-level failed to
sway the vote.
Enel Green Power ran into similar issues trying to permit a
100-megawatt battery in rural Littleton, New Hampshire. Testimony
included a fire chief showing photos purported to be from the APS
fire, which Enel said were not in fact from that event, according
to local paper the
Caledonian Record. Enel
withdrew its application in February.
â€œNimbyism is definitely a huge factor in the energy industry,
and weâ€™re seeing it rear its head with energy storage,â€ said
Daniel Finn-Foley, energy storage director at research firm Wood
Mackenzie. But local objections are unlikely to halt the energy
storage industry as a whole. â€œIt will affect individual projects,
but as a macro trend, I think the momentum is too high.â€
Make a good impression
Battery developers can defuse tension with proactive outreach to
communities, and by actively investing in local safety.
Strata Solar is building a 100 megawatt/400 megawatt-hour
battery in an unincorporated part of Ventura County, north of Los
Angeles. Development protocol required testing whether local water
infrastructure was up to county code; it was not, so Strata paid to
â€œThe fire department was really excited about that,â€ said
Will Mitchell, Strataâ€™s vice president of business development
for the West. â€œWhen they are in that area, they now have reliable
access to water.â€
The investment had nothing to do with the nature of battery
storage, Mitchell added. The plantâ€™s Tesla Megapack batteries are
designed to contain any fires and vent gases to prevent explosions;
the plan is that if something happened, firefighters would not need
to intervene. But the water upgrades will help them fight fires in
the surrounding area.
Mitchell himself serves as a volunteer firefighter and elected
fire commissioner in Marin County, north of San Francisco. That
perspective informs his engagement with local permitting agencies
during the battery development process.
â€œLike anything else in development, if you address it early
and take a proactive approach supported with facts and data, then
in my experience public officials and regulators will give it a
fair analysis,â€ he said. â€œIf youâ€™re meeting or exceeding
those codes, then you should be able to become part of the
Most people have never encountered a grid battery, so their
first impression of the technology may be from frightening news
reports out of place like Surprise. Developers have to
contextualize the current risks, while explaining the ways
batteries can benefit surrounding communities even as they help the
broader electricity system.
Source: FS – GreenTech Media
How to Keep Firefighters Safe From Batteries