Dear Members of the Menlo Park City Council -
Please ensure that any lithium ion-based grid-scale battery storage systems use battery subunits that are outdoors and will vent superheated gases skyward in the event of a fire. The Moss Landing disaster, in which an entire turbine hall full of container-size batteries burned up, was a readily-foreseeable outcome of the flawed installation design. Placing the containers within a reinforced concrete building ensured that when any single unit caught fire, the structure would concentrate superheated gases, causing overheating and thermal runaway of adjacent units and the loss of the entire building.
Literally everyone who reads the news knows that lithium batteries are subject to ignition and thermal runaway if they overheat, that they can randomly overheat due to manufacturing defects that can’t always be detected up front, and that often once these fires ignite they often must be allowed to burn themselves out as it’s often impossible to extinguish them. Therefore, if you’re going to build one of the world’s largest grid-scale energy storage systems, you need to ASSUME that a battery WILL overheat and experience thermal runaway and design the system in such a way that the ignition of one battery won’t cause any of the others to ignite. You could straightforwardly satisfy that design requirement through some combination of spatial separation of the subunits, physical separation of the subunits by earth, reinforced concrete, or similar, and venting of each subunit to the sky so hot gases will dissipate upward instead of being contained with the other batteries increasing the risk of chain-reaction overheating and thermal runaway.
Here is a photo of a Tesla grid-scale storage implementation. It appears that’s exactly the strategy they use: numerous subunits in the open air separated by gaps so a burning unit will mostly heat the sky not the adjacent units.
Yet the below system from Vistra using LG container-size battery subunits was designed in the exact opposite fashion: all the subunits were contained within a closed concrete building so hot gases would be concentrated not vented, maximizing the risk of the any fire spreading to consume the adjacent containers and then the entire building.
It requires no expertise in grid-scale battery systems design to foresee this scenario. I have no such expertise at all. If you’ve watched one YouTube video of a laptop battery or an EV igniting and one YouTube video of how hot gases behave during a fire inside a structure, you can foresee this scenario.
This appears to have been a failure at every step of the way:
- The solution architects at Vistra Energy who proposed enclosing a grid-scale lithium ion battery storage system within a reinforced-concrete building
- Anyone at LG who reviewed Vistra’s integrated solution design from a safety standpoint
- Every county planner and government body that approved this implementation
I strongly support implementation of grid-scale power storage to smooth out power supply-and-demand gaps, reduce the number of power plants needed, and reduce the need for natural gas-based “peaker” plants. But the companies who design, build, and operate these systems will also need to use at least minimal intelligence in their safety design to prevent readily foreseeable disasters like this from occurring, giving the entire industry a bad name, and creating public resistance to future battery system construction. And local permitting authorities will need to have staff who read the news and ask “What if?” instead of just assuming the service provider’s design is good and rubber-stamping it.
Please make sure we learn from this needless error by Vistra Energy and the Monterey County Board of Supervisors and don’t ever repeat it. Lithium ion-based grid storage batteries must be placed outdoors, not indoors.
Sincerely,
Eric Krock
755 Ramona Ave, Sunnyvale, CA 94087
Mobile 408-836-5230
