19 Comments
User's avatar
Chris Gorman's avatar

Fantastic analysis, thank you. CA's net metering makes this even more of a clown show that it's feckless residents misunderstand. Liberals and conservatives have blind spots of course, but with libs it's almost as though they welcome their own demise out of useless and misplaced guilt. Catastrophic empathy has turned California into the dumbest state in the Union.

Mary Mc's avatar

In VA (and I would guess nationally) any grid tied system must have an auto shutoff via the in erter which shuts it off from the grid, to keep from killing linemen trying to restore power, if unaware of the solar system.

Yes, if the system is self-contained and uses batteries for storage, the panels SHOULD be assumed to ALWAYS be creating power. Not doing so can get you killed.

Al Christie's avatar

Oregon, too - the micro inverters shut down the connection to the grid. But I don't think that stops the panels from producing voltage.

john's avatar

looks like California really promotes clean air

Mary Mc's avatar

😂😂😂 Check out the Moss Landing, Escondido and Otay Mesa fires. What a mess.

Jeff Chestnut's avatar

The accountability for this event is not an accident - it’s oversight and poor inspection. The decision to put solar on the facility’s roof is valid as that’s where solar should be installed - at the end user site. But the project management failed to include the proper procedure to control fire risk due to electrical problems. With a previous fire due to electrical malfunction you just have to think the organization has incompetent management. Now look at the environmental assessment to be done - chemical, physical, airborne hazards to assess. And then hiw much contamination was contained on the property and how much escaped? Irresponsible behavior should be met with a revocation of the permit to operate. The contractor performing the installation should have their license revoked - for the company entity and the individuals working on the job.

Not recognizing the panels would still generate and the batteries would still function with the main power disconnected is malpractice for the electrical design team - whether it was PE’s or not. The entire effort at this warehouse demonstrates a lack of professional competency. Treat the participating entities and individuals accordingly.

Bottom line, if you’re installing solar you’d better understand the risk and have mitigation and control strategies in place.

Al Christie's avatar

Wow - never thought about this kind of risk. An electrical fire that keeps going after the main is switched off!

Nothing has been said yet about what kind of danger is in that smoke...

I do have a healthy respect for the fact that solar panels generate electricity that can't be shut off.

Any electrical work, connections or disconnections, etc, is best done at night or after covering the panels with tarps or blankets.

Mary Mc's avatar

I would risk even that and my family used to design and install residential solar systems up to the state limit of 10kw.

Ronald Stein's avatar

The solar panels generate electricity that is stored in lithium-ion batteries.

The “chemical reaction” fire in those batteries can only be cooled but not extinguished by water.

Ed Davidson provides a clear explanation: https://www.linkedin.com/posts/ed-davidson-744b016_there-ya-have-it-water-does-not-extinguish-activity-7394165904965521408-ZuYd/

Mary Mc's avatar

That would depend on whether it is grid tied or not. If it is supposedly feeding excess power it will be grid tied and wouldn't need batteries.

Al Christie's avatar

Hybrid systems have smart inverters that can be programmed to switch back and forth to or from the grid automatically. And either way, the panels are still producing the same voltage differential - so the potential for powerful sparks remains.

Just like batteries - they sit there not doing anything until you switch a circuit on - but just try shorting the battery posts if you think turning off the circuit is enough.

Al Christie's avatar

True, but this fire started on the roof, so it couldn't have been caused by the batteries.

Ronald Stein's avatar

May not have been started by the batteries, but now that the batteries are involved, the challenge is how to distinguish that chemical fire.

Al Christie's avatar

Yes, I see your point.

Tom from WNY's avatar

Most do not know that anhydrous ammonia used in commercial refrigeration systems is explosive and flammable. Its an oxidizer; when mixed with water, extremely corrosive. HVAC systems consume a lot of electricity to drive compressors, fans and control systems for cooling. No doubt a thermal fault or spark ignited at an ammonia leak, causing this fire.

That's not to say a fire suppression system could not be added in to the construction of the solar array.

I'll also bet this fire will be used as an example as why we must destroy viable farmland and greenspace in rural areas to site solar farms instead of roofs on urban buildings.

Al Christie's avatar

This fire started on the roof.

A fire suppression system wouldn't help stop the fire - it was electrical.

I hope you're wrong about covering more good land. Better to just stop installing commercial sized solar altogether.

Tom from WNY's avatar

Fire suppression systems can be engineered for just about any application. You can use water or a chemical system for electrical equipment. Around 2000, Fike Corp. was marketing a FSS using pressurized ultrapure water for solid state electronic cabinets and systems.

No matter what you think, a CO2 flood discharge or an aqueous foam system (if the foam is chemically compatible with ammonia) would be preferred to this outcome.

Mary Mc's avatar

Doubt the company would be willing to pay for a system for a building that large. It will be interesting to see if their insurance covered solar fires or damage? Many won't these days.

Al Christie's avatar

Right, and I think many insurance companies will take another look at their rate structures when they hear about this type of fire.

There's two kinds of insurance - one for the cold storage company, and one (probably liability insurance) for the solar company. Yes, it will be interesting to see how this shakes out.