CNBC: Amazon Rooftop Fires Prompted Solar Panel Shutdown

Essay by Eric Worrall

Last Year Amazon was forced to take all their solar panels offline, after the panels caused six separate fire and explosion incidents. Amazon blames third party installers for the problems.

Amazon took all U.S. solar rooftops offline last year after flurry of fires, electrical explosions


Between April 2020 and June 2021, solar panels atop Amazon fulfillment centers caught fire or experienced electrical explosions at least six different times.

“The rate of dangerous incidents is unacceptable, and above industry averages,” an Amazon employee wrote in an internal report viewed by CNBC.

Rooftop solar is part of Amazon’s broad plan to zero out emissions by 2040.

On the afternoon of April 14, 2020, dozens of firefighters arrived at an Amazon warehouse in Fresno, California, as thick plumes of smoke poured from the roof of the 880,000-square-foot warehouse.

Some 220 solar panels and other equipment at the facility, known as FAT1, were damaged by the three-alarm fire, which was caused by “an undetermined electrical event within the solar system mounted on top of the roof,” Leland Wilding, Fresno’s fire investigator, wrote in an incident report.

A little over a year later, about 60 firefighters were called to an even larger Amazon facility in Perryville, Maryland, to put out a two-alarm blaze, local news outlets reported

In the intervening months, at least four other Amazon fulfillment centers caught fire or experienced electrical explosions due to failures with their solar energy-generating systems, according to internal company documents viewed by CNBC.

Amazon blamed third-party partners and vendors for the most significant problems uncovered by CEA and other teams working on facilities and sustainability initiatives.

Read more:

Rooftop solar may be inherently unsafe.

Solar panels are low voltage high amperage devices, similar to the low voltage component of an electric welding machine arc. Any installation mistake or structural failure can cause 10s, even hundreds of amps to go where it is not intended.

Solar Panels are also usually mounted on Aluminium frames.

Aluminium has some attractive characteristics, it is cheap, easy to drill and cut, lightweight, which reduces or eliminates the need to reinforce existing roof supports, and is corrosion resistant.

But Aluminium also has some significant downsides. Aluminium has a very low melting point, it melts at around 1200F, far below the melting point of other common structural metals like Steel. Aluminium is a good electrical conductor, so it can carry and potentially be weakened or completely melted by stray currents from high amperage solar panels, though Aluminium is also an excellent heat conductor, which might mitigate the risk of melting. Aluminium is also vulnerable to salt or electrical corrosion, as any boat owner would know. Salt, electricity and aluminium is a bad mix, even small stray electrical currents can cause rapid oxidation and structural failure. Desert dust and sea breezes frequently contain a lot of salt.

Worst of all, hot Aluminium can form dangerous, difficult to extinguish flammable thermite mixtures which burn at many thousands of degrees with a wide variety of structural oxides, like titanium oxide, which is the magic pigment in heat reflecting paint, rusty steel, some roof tile materials, and glass.

I don’t know whether the chemical ability of electrically heated aluminium to form high temperature combustible mixtures with a wide variety of normally non-flammable structural materials is a factor in solar rooftop fires, but this seems a real possibility.

My question – if a large company like Amazon can’t get installers to do their job right, what hope to ordinary people have? Time will tell if insurers start adding a “rooftop solar” premium to household policies. At the very least, everyone who wants to install solar panels should review whether their rooftop material can form a dangerous thermite mix with the solar panel frame.

Update (EW): The following video is Aluminium mixed with internal wall plaster creating a white hot flame.

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Howard Dewhirst
September 2, 2022 2:40 am

And not to forget that solar panels can NOT be turned off/stopped from making electricity – if the sun is up. Firemen are not able to hose them down either; problemo ….

John Hultquist
Reply to  Howard Dewhirst
September 2, 2022 9:01 am

A Consumer’s Guide to Fire Safety with Solar Systems | Department of Energy

It seems to me Amazon had faulty equipment or a team of installers without a clue. It is a guess, but there are about 3.5 million and fires are few. The rate of failure for Amazon is an anomaly.

Reply to  John Hultquist
September 2, 2022 10:15 am

Yep a really rare event. 7 out of 240 so far. Over 2.5% fire rate, obviously safe.

Paul Penrose
Reply to  Drake
September 2, 2022 11:12 am

I’d speculate that large commercial installations are at more of a risk since they have the larger systems that can generate huge currents. Home systems, being smaller, are less likely to exhibit such failures. That doesn’t make them “safe”, just safer. Everybody needs to assess the risk for themselves, but we need to have reliable, non-biased data to do that, which is where the problem lies.

Tim Gorman
Reply to  Paul Penrose
September 2, 2022 3:13 pm

Go drop a 12″ crescent wrench across the 12v battery in your car and see if you think they are “safer”. Now, increase the current possibility by a factor of ten (or more) for a whole house battery string capable of lasting three days of no grid power.

Carlo, Monte
Reply to  Tim Gorman
September 2, 2022 8:45 pm

This when Kirchoff will rise up from his grave and tell you that you are violating one of his laws.

Reply to  John Hultquist
September 2, 2022 11:10 am

Walmart had a 5% failure rate om their solar panels.  Not what I would call a “few fires.”  One and twenty chance is not good in having those odd of having your house burn down.

John Hultquist
Reply to  mal
September 2, 2022 12:30 pm

That’s the point. These commercial installations are anomalies. Find a 5% failure on single family homes, or whatever it is.

Kit P
Reply to  John Hultquist
September 2, 2022 12:48 pm

What John said is BS and what DOE said is BS!!!!

a solar system spontaneously bursting into flames is an extrehingsmely rare occurrence, according to the Solar Energy Industries Association.

One of the things I was trained to do and did was hazard assesments. If fact it was a DOE training class.

‘extremely rare’ is being hit by a rock from outer space.

The frequency of an initating even, electrical fire, is known. That is why places I worked that made electricty had a fire brigade trained in electrical fires.

The benefit of having electricty is huge, the risk is small.

Since the amount of electricty produced by roof top solar is small, the benefit is small.

The purpose of solar is to tell people you have solar. When fire trucks show up, it makes the news. As myh dad said, one awshit wipes out a thousand attboys.

Robert B
Reply to  Kit P
September 2, 2022 1:51 pm

Wise man, you dad.

Reply to  John Hultquist
September 2, 2022 6:31 pm

If you read the article, Amazon has tried numerous solar contractors and it appears a number of them don’t know what they are doing, thus the warehouse fires. They’ve been trying to hire experts directly for installations but haven’t had much luck, so far, it seems.

September 2, 2022 2:54 am

“…an undetermined electrical event…”

Under net zero there won’t be many of those.

September 2, 2022 4:06 am

We nominated to be notified of new wind, solar and BESS backup in and around our town. I know that there are developments that we don’t have all the detail on but I’ll list what we have so far. I can confirm that 124 square kilometres of prime agricultural land, so far, will be utilised for wind, solar and batteries. Solar equates to 47 square kilometres at a total of 1,587MW of nameplate capacity. Wind, so far, equates to 60 wind turbines each at 7MW and standing 280m high and 200m wide and totalling 420MW which will be installed on 77 square kilometres of land. This project includes solar projects will include a substation, potentially two, and 11 kilometres of its own transmission lines.

Most of the projects include BESS backup and the total that I know of, so far, equals 1,120MW of Backup batteries. They seem to be pairing up batteries to the equivalent of the wind or solar. A 400MW solar project has been approved with a 200MW BESS backup. But the 500MW solar currently up for approval includes a 500MW BESS and the 420MW of wind includes a 420MW BESS backup. Not sure about the backup for the 600MW proposed project.

They do not care about the increased fire risk or how they might fight a fire at a renewables site. We had a fire last Friday which started across the road from our existing thin film cadmium/tellurium solar project. The fire required more than a dozen fire fighting units and three helicopter water bombers. The paddocks were too boggy for the big trucks to get close but fortunately the farm dams were full and the water bombers extinguished the flames, which were meters from the solar panels and the substation itself. This solar project is 4 kilometres from our town. We were lucky this time, the winds were light and there is a fair amount of ground water around. A summer fire with strong winds would have seen a different outcome. This one took four hours to extinguish and burnt out 68 hectares of grasslands. The fire came within metres of a farmhouse as well as the solar panels and substation.

Reply to  Megs
September 2, 2022 5:21 am

Why not a few acres and a predictable and sustainable CCGT plant…problem solved.

D. J. Hawkins
Reply to  Ron
September 2, 2022 6:03 am

Stop making sense!

Reply to  Ron
September 2, 2022 3:11 pm

Wouldn’t that be grand! They are shutting down our nearest coal-fired power plant within the next few years. That would be an ideal place to put either a HELE coal-fired power plant or a CCGT plant, the transmission lines are already there. Instead there looking to use the site for a 750MW BESS. No mention of wind or solar so I guess it will be fed by the grid?

Australia thinks it will lead the world with these grand plans. We have a population of less than 25 million people. Just how do they think they’re going to finance this infrastructure? Can you imagine the cost of a BESS this size?

John Hultquist
Reply to  Megs
September 2, 2022 9:08 am

Note that the use of water (water bombers) suggests the info in the first comment (“not able to hose them down“) is incorrect. Solar panels are not Li-batteries.

BESS – Battery energy storage systems

Reply to  John Hultquist
September 2, 2022 10:19 am

Sure, it would be easy to hose down 47sq kilometers of solar.

John Hultquist
Reply to  Drake
September 2, 2022 12:36 pm

Are you suggesting 47 sq k of ground mounted panels are all on fire at the same instant?
I took Megs to mean a total of 47 from multiple projects.

Reply to  John Hultquist
September 2, 2022 3:01 pm

You are correct. But the distances between the proposed projects are not great. We had a huge fire not too far from here at Leadville NSW in 2017 which burnt out 50,000 hectares. If a big fire front came towards our town and once it hit the renewables there would be no stopping it. Our beautiful historic town would be destroyed.

Reply to  John Hultquist
September 2, 2022 2:44 pm

I know what BESS are. My point in mentioning them is the size of them. They are all much bigger than the battery which was installed in Victoria last year, which is bigger than the Hornsdale SA “biggest battery in the world” which is now 150MW after being extended. The battery system in Victoria caught fire 3 days after it was commissioned and it took three days to burn out.

If you read my post properly you would see that I said that they just managed to stop the fire a few metres from the panels. That particular solar project is 87MW of thin film cadmium/tellurium. We were told by a fire-fighter that if a fire started within the solar project that they would let it burn. They said that the toxic smoke that it would produce would be too dangerous for them to be anywhere near. They said that the only way to fight a fire on that solar project was from the air. During the summer fire season water bombers would be stretched thin.

Even standard solar panels produce toxic smoke during a fire. And no, you can’t train a hose directly onto panels. Even if the inverters are switched off the panels are still live in the daytime. At best they can fight fires at the perimeters of the solar project. How would they protect the perimeters of a solar project that takes up 18 square kilometres? The land around here is so boggy after plenty of rain the past two and a half years that the fire trucks can’t traverse the terrain.

John Garrett
September 2, 2022 4:48 am

NPR headline:

“A Tesla burst into flames during a crash test. The organizer admitted it was staged”

NPR always cites nameless, unidentified “experts” when broadcasting propaganda and advocacy pieces (see climate).

When NPR uses nameless, unidentified “experts” listeners can be certain of one thing:
NPR isn’t reporting both sides of an issue.

Last edited 3 months ago by John Garrett
Reply to  John Garrett
September 2, 2022 5:02 am

NPR never reports both sides of the issue. I used to listen to NPR extensively. One day, I realized I was starting to yell the other half of the story at the radio, explaining why everything they’d said was really to opposite when taken in context. Then I just turned them off. Never listen to NPR anymore.

John Garrett
Reply to  Spetzer86
September 2, 2022 5:22 am

I agree and for that reason I no longer listen to NPR but I do read their website (and I have to force myself to do that).

The reason? I need to know what lies are being fed to a not insignificant portion of the population.

Reply to  Spetzer86
September 2, 2022 8:12 am

Public news broadcasting media organisations all around the world inevitably become just a collective of leftists who think the organisation’s main mission is to ensure that the public is steered to the “right” (ie “socialist”) content.

I cite NPR, BBC, CBC, ABC.

Mike Lowe
Reply to  Mr.
September 2, 2022 12:22 pm

I suppose TVNZ is too inconsequentally small to merit inclusion?

Reply to  Mike Lowe
September 2, 2022 4:20 pm

They’ve got tv in NZ?

Reply to  Mr.
September 2, 2022 8:07 pm

Of course they do, Mr.

. There’s one TV in the airport tuned to CNN.

Smart Rock
Reply to  Spetzer86
September 2, 2022 9:36 am

Exact same experience that I had with CBC radio. I stopped listening to it after they managed to inject climate change messages into every news or current affairs program where they could see even the most remotely tangential relevance. The boiling rage that their outright untruths induced in me was starting to threaten my physical and mental health.

That was about 5 years ago. After the BLM riots, CBC messaging expanded to informing us that Canada is a rαcisτ society and apparently beyond redemption. I get this from the CBC website, which I occasionally visit when I feel a bit of optimism about the future of the human race, and need to get back to my normal state of utter despair.

Thankfully, I’ve never owned a TV.

Reply to  Smart Rock
September 2, 2022 8:12 pm

Thankfully, I’ve never owned a TV.”

Indeed you are one very Smart Rock. 👍

September 2, 2022 5:31 am

Problems due to “third party partners and vendors” at widely scattered installations across the country? Seems unlikely unless it was a standardized installation methodology which caused the issue, and then it would seem that after the first problem was identified, the others would be corrected before it happened elsewhere. Not sure I’m buying the excuse.

So instead of reducing, Amazon has increased CO2 emissions by burning rooftops and hazardous solar panels, at exhorbitant cost to repair, I’m sure. Good show.

Last edited 3 months ago by BobM
D. J. Hawkins
Reply to  BobM
September 2, 2022 6:11 am

The way Amazon approached the solar installations was to hire third party firms that execute all the agreements, do the installation, and track all the credits.  The way these firms make money is to keep the renewable energy credits for themselves, which are often worth 2-3X the value of the energy produced, which is the part Amazon gets credit for exporting to the grid.  It appears they used multiple firms across some 50 locations nationwide, which would explain why it’s such a hodge podge.  I would guess that the root cause is the failure of Amazon to establish an internal specification that would address the design and equipment selection across the company and thereby create a benchmark for installation quality.

Carlo, Monte
September 2, 2022 6:49 am

Using the popular term “solar panels” is something of a misnomer here — in order to put them (the panels, i.e. PV modules) into use, multiple modules have to be connected in series to increase the voltage. Together with a DC-AC inverter, this turns the “panels” into a PV system. In large systems, like on an Amazon warehouse roof, multiple series strings are also connected in parallel to increase the current. Even larger systems will have multiple inverters. As a result, a PV system has a lot of DC and AC wiring.

What causes fires such as these? #1—bad system design, #2—improper or faulty system construction.

Aluminum is not a very big issue in PV systems; many modules sold do not have outside frames, and larger systems need steel instead. In any event, metallic structures have to be correctly grounded. This is probably the #1 cause of PV system fires. There have been cases of system fires caused by the steel conduit inside of which interconnection wires were run. A pipe union that is not tightened correctly can initiate an arc.

The real issue then is the system integrators that have popped up like weeds in the spring, feeding on subsidy and grid payback cash without much experience. Together with local jurisdiction code inspectors that may not be well-versed in the National Electrical Code for PV, fires can happen.

Tim Gorman
Reply to  Carlo, Monte
September 2, 2022 7:40 am

Once you develop a resistance in a connection carrying lots of amps you begin to build up heat. If the connection is bad the heat will only make it worse. When it gets hot enough that insulation starts to melt then you get shorts and that can make things exponentially worse. Fires are the inevitable result.

If I were engineering these systems I would want alarms that monitor current all throughout the system. Catch problems early and isolate them. Of course, that’s going to hurt the cost curve for solar panels. So be it.

Reply to  Tim Gorman
September 2, 2022 10:45 am

The other problem is that the current running through these systems is DC, and interrupting a high current DC supply is difficult. Because of inductance and magnetic fields, once a DC current gets started, it wants to keep going.
If the path is disrupted, the collapsing magnetic field causes the voltage to increase which often means that your relays are going to arc.

Carlo, Monte
Reply to  MarkW
September 2, 2022 1:26 pm

This true, once an arc gets started, for whatever reason, they have been seen to propagate along the interconnects inside and between modules.

Carlo, Monte
Reply to  Tim Gorman
September 2, 2022 1:24 pm

Another issue is that in Europe they like everything to be ungrounded, and a lot of this practice has spilled over into North America. I can understand why it can be allowed for a small residential AC appliance, but a large power-generating PV system?

Tim Gorman
Reply to  Carlo, Monte
September 2, 2022 3:10 pm

Any power generating system should have all metal parts that could be exposed to power because of a failure connected to a safety ground that would trip some kind of a breaker thus removing the power before the failure could cause a fire or fatality.

Gunga Din
Reply to  Carlo, Monte
September 2, 2022 7:45 am

So … a solar storm waiting to happen?

Curious George
September 2, 2022 7:54 am

A tirade against aluminum. Let’s stop using it anywhere. BTW, it was also implicated as a possible cause of Alzheimer’s disease 🙂

John Hultquist
Reply to  Curious George
September 2, 2022 9:12 am
Gordon A. Dressler
September 2, 2022 9:44 am

AKA the Law of Unintended Consequences.

September 2, 2022 9:47 am

Add rooftop solar firefighting to the all the green jobs count used by lobbyists.

September 2, 2022 11:18 am

Anyone know if having solar panels on your roof increases your home insurance costs?

Carlo, Monte
Reply to  Jit
September 2, 2022 1:31 pm

The thing about roof-mounted PV systems is that its just about the worst way to use them. Modules run much hotter because of reduced ventilation on the rear side, and they are almost never oriented correctly. Both of these throw energy (and cash) away for little gain.

Kevin Stall
September 2, 2022 1:44 pm

Brighton UK Post office had a similar fire years ago with its rooftop solar.

Robert B
September 2, 2022 1:48 pm

“The rate of dangerous incidents is unacceptable, and above industry averages,”
Surely that industry average needs to be zero before covering water supply canals?

September 2, 2022 1:51 pm

Amazon should rethink it’s investment policies and direct future investments in nuclear.

Rich Lentz
September 2, 2022 4:40 pm

Only two mentions of Inverters and No mentions of Squirrels. Both are the probable cause of these fires. Some systems will have Inverters at the panel. Squirrels love to eat the insulation. Also the main reason for the fires in the 4X4 transformers in the back yards of over a 1/4 of the homes in any newer development.

  1. Squirrel eats insulation of a wire.
  2. Squirrel eats insulation of a second wire.
  3. Squirrel relieve self while standing on wires.
  4. Sparks fly, squirrel cooks, fire melts more insulation, wires make solid conduct of the copper conductor. Fire spreads down the entire cable to other equipment in series with each other, and the big fires begins.
Reply to  Rich Lentz
September 2, 2022 6:49 pm

You may have just made me lose interest in getting solar panels of any kind. I presume chipmunks are just like squirrels? We have two central air A/C units. Although they didn’t cause damage, the Heat and Air guy I had out found two fried chipmunks in the larger unit and one in the smaller unit. He did something to make it harder for them to get in and, so far, so good.
They are cute little critters but this was most annoying. OK, it was even more annoying for the chipmunks but they didn’t have to pay for the repairs to fix the damage they did while on their way to electrocuting themselves. I’m sure they’d love the wires on solar arrays just as much.

Reply to  KcTaz
September 4, 2022 6:31 am

Twice a mouse got into my Heat Pump in the fall and I had no heat, A mouse or rodent had eaten through one of the wires. Cost $250 for HVAC service to repair the first time. As I saw what was wrong I replaced the wire my self the next time, and now keep Rat bait inside the unit in an area that cats/dogs can not get into.

September 2, 2022 6:29 pm

This is from 2021. It appears, like everything else with renewables, they get installed first and deal with problems and issues later.

The Roof Is on Fire: Do Solar Panels Hinder Firefighters? via @string

This covers ground and rooftop solar. It appears getting firefighters trained on rooftop solar is a work in progress and in its infancy. I’ve been thinking of installing solar for quite some time but the roof fire issues are concerning and we have a small lot with no really suitable place for ground solar to work effectively. I, also, am concerned about adding to the pollution burden and safe disposal of these things for which there are none as far as I can tell. Most are not recycled as I understand it due to cost.

Kit P
Reply to  KcTaz
September 3, 2022 9:55 am

When you are thinking about solar consider this. Solar is just another energy scam.

I have done business plans for renewable enenrgy projects for electric utilities using thier standard calcualations.

I have yet to see an honest solar evaluation does not show it a scam.

That is assuming the they produce the expected amount which they never do. I expect zero based what I find more often than not.

In one case the net geration to the grid is negaiative. The web site show gneration at the panel but not delvered. I know a guy.

If is an investor own utltiy, there is jail time for misleading investors, so that is a source of honest information about solar but it takes digging.

It is a racket. The scam artist tell how much you (might) save on your utltiy bill. What they do not tell you is that they will send you a $1200 bill if the panels do not produce enough power.

This the experince of family who bought a house with an PV system in Califonia. Why would you expect a place know for dense winter fog and a summer marine layer to be a good solar resource?

September 4, 2022 6:40 am

Twice a mouse got into my Heat Pump in the fall and I had no heat, A mouse or rodent had eaten through one of the wires. Cost $250 for HVAC service to repair the first time. As I saw what was wrong I replaced the wire my self the next time, and now keep Rat bait inside the unit in an area that cats/dogs can not get into.
As I worked for an Electric Utility I am very aware of what rodents can do to transformers. The same can/will happen to rooftop or ground mounted solar panels and cause fires. That $250 to put a crimp on wire connector is likely what you would have to pay to do the same for a wire in a solar panel for the average home owner. If you are going to have a solar panel learn how to install and repair yourself or you will lose money. Average annual expense for a SP will be in the same ballpark as maintenance is for an HVAC. Probably more if it is on the roof. I would also recommend placing all exposed interconnecting wires, cables, in metallic conduit/flex-conduit.

Last edited 3 months ago by usurbrain
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