It seems like hardly a day goes by that doesn’t see some news story splashed across our feeds that has something to do with Elon Musk and one or another of his myriad companies. The news is often spectacular and the coverage deservedly laudatory, as when Space X nails another double landing of its boosters after a successful trip to space. But all too often, it’s Elon’s baby Tesla that makes headlines, and usually of the kind that gives media relations people ulcers.
The PR team on the automotive side of Tesla can take a bit of a breather now, though. This time it’s Elon’s solar power venture, Tesla Energy Operations, that’s taking the heat. Literally — they’ve been sued by Walmart for rooftop solar installations that have burst into flames atop several of the retail giant’s stores. While thankfully no lives have been lost and no major injuries were reported, Walmart is understandably miffed at the turn of events, leading to the litigation.
Walmart isn’t alone in their exposure to potential Tesla solar problems, so it’s worth a look to see what exactly happened with these installations, why they failed, and what we as hackers can learn from the situation. As we’ll see, it all boils down to taking electrical work very seriously and adhering to standards designed to keep everyone safe, even when they just seem like a nuisance.
A Solar Panel on Every Roof
Solar panels have always been a key part of Musk’s vision for Tesla, which seeks to eliminate the need for fossil fuel transportation. Tesla’s battery-powered cars were designed from the outset to be charged by the sun, with rooftop solar arrays installed everywhere.
And so the idea for a company called SolarCity was dreamed up by co-founders Peter and Lyndon Rive during a road trip with their cousin, none other than Elon Musk. Musk would serve as the new company’s chairman and would be actively involved in running the company, whose early business model involved door-to-door sales of rooftop solar arrays directly to residential customers. Early adoption in the USA was partially fueled by federal and state green energy tax credits which partially offset the cost of installing an array. Later, SolarCity began hawking installations with no up-front costs that would be paid over 20 years with a cut of the power produced. That ended up being attractive to enough customers that business — along with SolarCity’s debt — boomed.
At about this time, SolarCity got into the commercial market, with large installations at businesses looking to both reduce their energy costs and burnish their green reputation with customers. Intel and eBay were early customers, as was Walmart. The retailer would ultimately enter into agreements with SolarCity to install and maintain arrays on more than 240 of its stores.
Burning Down the Store
According to Walmart’s suit (downloadable PDF), the first rooftop fire was in 2012, atop a store in Long Beach, California, which caused $90,000 in damage. It’s not clear what the root cause of that fire was, but 2016 fires at stores in Milpitas, California, and Lakeside, Colorado were blamed on “faulty connectors”. A fire at a store in 2017 was pinned on “Tesla’s faulty installation of conduits”. Tesla was blamed specifically in this fire because SolarCity had been purchased in full by Tesla in 2016 for $2.6 billion.
Then, between March and May of 2018, a series of fires occurred at three Walmart in rapid succession, first in Beavercreek, Ohio, then Denton, Maryland, and finally Indio, California. A firefighter was injured, customers were evacuated, sales were lost, and repair bills mounted. Having had enough, Walmart demanded that Tesla de-energize every surviving solar array on every Walmart. Even that was not enough to stop the carnage, as a de-energized array in Yuba City, California, somehow started arcing and burning. How that fire started is a mystery.
Walmart hired consultants to comb through the debris of these fires and to inspect the workmanship of intact arrays and found quite a few issues. Bearing in mind that lawsuits are a laundry list of claims that the plaintiff uses to put the maximum blame on the defendant, and that the consultants were hired by Walmart and are therefore likely to be biased toward their client’s position, the investigation revealed some pretty shoddy workmanship, which Walmart alleges was due in part to SolarCity having overextended itself during the huge increase in its business during the time these installations were performed.
Among the problems that Walmart’s consultants discovered by investigating the surviving solar arrays were improper grounding, poor wire management leading to insulation abrasions and wear, and lack of as-built drawings and proper documentation. But the most glaring errors alleged by the inspectors were the presence of hotspots in the arrays, and improper installation of the connectors used to string together the solar panels.
Hotspots in photovoltaic arrays occur when one or more cells in a series-connected string of cells are underperforming for some reason — say, by being shaded by leaves or dirt. The shaded cell or cells can then become the current limiting element in the series circuit, which can lead to reverse-biasing of the bad cells. This essentially dumps all the power from the good cells into the bad cells, heating them up to possibly the point of failure due to melted solder joints, cracked silicon, and, as appears to be the case with the Walmart fires, ignition of the materials used to encapsulate the cells. Walmart’s investigators discovered multiple examples of hotspots in intact arrays, which they allege Tesla either missed or didn’t bother to look for.
Walmart’s consultants also found fault with the installation of connectors. Like most solar arrays, the Walmart panels were strung together with MC4 connectors. These are industry-standard connectors manufactured in the billions, and are designed to provide fast, weatherproof connections in the field. They consist of a crimped metal male or female terminal, a locking weatherproof shell, and a strain-relief gland for the conductor. Walmart’s investigators provide a photo of one MC4 connector that shows the threads of the strain-relief partially exposed. The lawsuit contends that the installers failed to use “a special tool known as an MC4 torque tool” to tighten the glands. Stäubli, one of the leading manufacturer of MC4 connectors, recommends the use of a calibrated torque wrench to achieve a final torque of 3.5 to 4.5 N-m in its MC4 product guide, a tool which apparently was not in the Tesla installer’s toolkit.
It’s hard to say whether the exposed threads in the photo really mean that the glands weren’t properly tightened, though. Weatherproof glands like these work by squeezing a flexible sleeve against the outer jacket of the conductor, and since MC4 connectors can be used with wire between 14 AWG and 8 AWG (1.5 mm2 to 10 mm2), the amount the gland will settle on the body threads will vary. Since the point of the gland is to provide strain relief and protection from water and dust intrusion, Walmart’s consultants may have made a better case by showing compromised connections inside of an allegedly incorrectly torqued connector. Sadly, they did not.
In the final analysis, it’s hard to avoid the impression that SolarCity and Tesla did a poor job of installing and maintaining these arrays. What comes from this is up to the courts to decide, but for now, anyone who does solar installations would be well advised to pay attention to wire management, connector installation, and array cleaning to make sure a similar fate doesn’t befall. And anyone who has a SolarCity array on the roof of their house might want to have it inspected very carefully in the very near future.
61 thoughts on “Solar System Wars: Walmart Versus Tesla”
not familiar with the US legal system, but this seems like a smoke and mirrors maneuver to divert attention from something else.
smoke… mirrors… yeah I’m on fire!
Thanks for the great article. It is sad that such a great opportunity for Solar applications installed in a non controversial locations (where no tortoises live) were disrupted by simple shortcuts in quality.
A drone with IR cam can see those hotspots in panels. Just maybe having a flight every quarter could prevent those kind of faults. I’ve seen some sub standard installs, its like no-one ever heard of a drip loop before. The power company near me has a solar trailer demo that they bring to events. The wires come straight off the roof into the trailer with no drip loop at all, at the least it will cause mold.
There is a huge solar farm in FL I know about that keeps having their inverters/transformer boxes explode!
The suit actually contains a drone image used by SolarCity/Tesla to look for hotspots. The suit complains that the image was fuzzy and unable to pick up hotspots. FWIW.
So, something with a lot of forced cost reductions develops problems ….. Who could have imagined ? The horror !!!!!
I hope that Tesla has(had) enough smarts to track all contractors and quickly weed out the ones that were using shortcuts to save time and made bad connections, bad wire routes etc. They should have settled this and admitted fault waaaay back when these problems first emerged. Now it will cost them 10 times as much as well as reputational losses.
A highly relevant events happened after this: Walmart put the lawsuit on hold because they will jointly resolve the issue. Now why would Walmart drop this if they have a good case?
Tesla has a big focus on safety, with cars but also solar. If you look at their patents, perhaps even more than 1 in 5 is related to safety in some way. But something very different is going on than the media report on:
Risks of fire and who’s liable to pay damages is arranged in the contract.
Before Walmart tried to sue Tesla, Walmart sent them a letter asserting breach of contract:
This is worth a read, but it’s lengthy. My personal take: The solar panels are part of a power purchase agreement (so panels aren’t owned by Walmart). Walmart didn’t like their contract for commercial reasons anymore. (note: solar has gotten a lot cheaper since 2010, when the first solar arrays were installed)
The following comment includes a good summary by KeepItReal copied verbatim from: https://cleantechnica.com/2019/08/22/walmart-sues-tesla-over-rooftop-solar-fires/
Walmart had disconnected the panels, but they argue they don’t owe anything further as no power is being generated.
Thus Tesla stated they breached contract for disconnecting all 248 systems when there was no issue with 244 of them. Tesla, since January 2018, has worked with Walmart to come to a common testing scheme yet Walmart is dragging its heels while Tesla loses money on the generation side.
This is typical Walmart bullying a smaller entity and Tesla wanted to assuage them as they were a large customer – but as the attorney stated ‘enough is enough’ and Tesla finally sent Breach of Contract language.
The fires likely are more Walmart’s fault than Tesla (Solar City). While there may have been some loose connections under panels, there should have never been detritus under them to ignite. Walmart simply didn’t keep their roofs clean.
Sure, you find out if others are bad by burning down a couple buildings. Meanwhile your insurance is void because you ignore a known risk. Evil Walmart. Leaves on the roof can ignite under the panels? Well, who would ever expect leaves on a roof? Obviously Walmart’s fault.
Passively ignoring a known risk is negligence. It’s even worse if your actions are causing the risk to persist and grow over time. I only know the story from what I’ve read such as legal letters from both parties, but it seems like Walmart was effectively stalling the process that was contractually agreed upon. This prevented Tesla from inspecting and remedying any problems as they are found.
Salient detail is that at least some of the solar array had already been disconnected at the request of Walmart before the rooftop fire occurred. I can’t imagine how a disconnected system can still cause a fire, but I’m no expert. I’m not disputing that there was a fire, but just saying that it’s suspicious and we probably don’t know the full story. Usually when this is the case, I wouldn’t blame a company, but in this case Tesla shorts are having a field day claiming it doesn’t care about lives while the opposite is true, only to make money or attempt to destroy, discredit or slow down a company that is threatening their business prospects.
The oil & gas industry makes more profit in a week than it costs to short 50% of Tesla’s stock. Everyone who buys an electric car never visits a gas station anymore (except for a snack or bathroom break). O&G isn’t just lobbying in politics to pollute a bit longer, in addition, they also try to distort public perception. Organizations like Koch Industries are spending millions on campaigns to emphasise battery production with humanitarian concerns.
It’s not even a little ironic, since O&G companies are SO concerned with humanitarian issues!.
The problem is that most people don’t connect the think tanks to the O&G industry, which they obviously try to hide.
Just disconnecting a PV panel doesn’t stop it producing power when the sun shines on it. If there’s a short or bad cells or some other defect it could cause a fire.
Open circuit PV modules, arrays do have a higher output voltages (open circuit voltage) than those connected to a load (e.g. Inverter @ max. power point voltage). The modules are producing this voltage, as soon as light shines on the them. Higher voltages do mean smaller creeping distances, so if there are possible unisolated parts between the poles or ground (in the U.S. most commonly minus is even grounded), the risk of arcing increases, and so the fire risk.
Nice. Patenting safety items so nobody else can use them. Thanks for looking out
Check out Tesla’s patent pledge: https://www.tesla.com/about/legal#patent-pledge
All of Tesla’s patents, now and in the future can be used in good faith, indefinitely. Even if Tesla would sell a patent, this same policy will have to remain applied by the buyer. This includes hundreds of SolarCity patents, quick scan indicates that it’s over a thousand patents in total (and counting).
If Tesla litigates (first) when a company uses their patented safety or sustainability technology, I will eat my hat. This is quite safe to say, because they won’t have a case because of their pledge.
Smells wrong. Literally the only purpose of a patent is to prevent other people from using your tech. If they wanted to make it open they’d just publish it without patenting.
Patents cost a lot of money and they wouldn’t spend it if they had no intention of ever using them. So something here doesn’t ring true.
If they didn’t patent it, then someone else would, and make the technology proprietary to them.
They have the right to enforce patent law if someone comes along and abuses the patent by making millions off of it, however they have no intention of going after small businesses or private individuals for using the patent idea on a personal project or something designed to provide improved safety or efficiency in a business setting. Also, they still would want to control the patent so a patent troll doesn’t use it for nefarious purposes. I will admit I’m slightly biased towards Musk and Telsa, but this patent pledge should be shared. It’s got a great message behind it and it helps humanity, not just a cash cow company.
The purpose of patents has historically been to encourage the disclosure of and encourage the development of new inventions by granting a temporary government-granted monopoly on something made by an inventor.
“for using the patent idea on a personal project”
That is already legal anyhow. You can build a patented thing for yourself any day – just as long as you don’t sell it or build it for someone else. That’s because patents apply to scientific inventions as well and peer review would become mighty difficult if you couldn’t build the same thing.
“Early adoption in the USA was partially fueled by federal and state green energy tax credits which partially offset the cost of installing an array. ”
Partially? If you apply both state and federal level subsidies, you can (could) shave off 75-95% of the cost. You also get tax credits for things like building a garage underneath your solar array, because it’s considered part of the infra.
Plus you get net metering which means you get free prime-time peak electricity in exchange for pushing all your electricity onto the grid at non-peak times. Without the subsidies, the prices paid for residential solar power would be essentially negative, and practically nobody would be buying the arrays.
At peak subsidy, solar power was getting over $250/MWh in taxpayer money, while the system price of regular electricity was around $40/MWh.
It still makes absolutely no financial sense, since all that money went to China where 80-90% of solar panels are made. It went to the lowest bidder, which is those who sold you old tech and didn’t develop anything new, so the point of the subsidies was almost entirely lost.
The idea that a subsidy will kickstart a technology is patently false, because the industry that provides the technology has two options: a) spend some of the profits they earn on developing better products at cheaper prices, while their competitors don’t, b) selling expensive first-generation products at high margins while dragging their feet on the R&D because everyone’s getting guaranteed prices and profits.
That’s why in the US, all the major industry investments on renewable energy went in lock-step with the extensions on ITC and PTC. Every time the subsidies were about to expire, the industry went full stop on new investments – so the federal government renewed the subsidies to keep up with their own targets.
Solyndra Is still a pain in the gut for me. This was a company developing a new, cheaper to manufacture, and more efficient solar panel technology that was undercut by cheap traditional amorphous silicon panels from China selling in the US heavily subsidized. That pushed US manufacturing out of business and into bankruptcy. THEN, a Chinese Company came to the “rescue” and bought the patents. AND THEN American companies had to come to the defense of the Chinese manufacturers to be able to have some product on hand to be able to install so customers could take advantage of the tax credit.
Yes, except the CdTe technology “developed” by Solyndra is a dead end because it contains Cadmium which is a hazardous waste problem in the making, and Tellurium, which is rare as teeth on a hen and the supply is limited. Even if they did put the price down otherwise, on scaling up production, the limited raw materials supply will turn the marginal cost curve up like a rocket.
So Solyndra too was yet another subsidy grab – a good story, but ultimately they were going to fail and I think they knew it from the very beginning. Yet they made still they scored $528 million from Obama, $198 million from private investors, and $25 million from California before they declared bankruptcy. They’re not the only ones: SoloPower got $197 million from the same fund for making CIGS panels, then folded, and a number of smaller companies also cheated the feds and California for money.
The thin-film cells all of these companies were making are a niche product for applications where price and efficiency are secondary concerns – they were not a solution to the clean energy problem any more than fitting generators to hamster wheels.
Some people from Solyndra stated they proposed a reconfiguration of their existing factory to improve workflow and efficiency to be able to increase production and reduce costs. But the higher ups figured it’d be better to get a massive grant from the Obama government and build an all new plant. They never made any of their tubular panels at the new plant.
The supposed superiority of using tubes coated on the inside was that they should produce the same power throughout most of the day as the sun went across, gaining the advantage of azimuth tracking without the complexity and expense. But that would require mounting the panels above a suitably reflective surface that would have to be kept clean to reflect the most light to hit the back sides of the tubes.
As Luke notes below, the metals Solyndra used were toxic and/or rare, which would have eventually bitten Solyndra on the arse for environmental and cost reasons. Any sudden spike in Tellurium prices would’ve sunk the company.
After the company assets were auction off there were huge amounts of the uncoated special high strength glass tubes left over. Rather than trying to find anyone to pay a pittance or even to just take them to find a use for them, they got shoved off a loading dock to smash. Part of Obama’s half billion of our tax money literally dashed to pieces.
“Obama” didn’t spend those trillions on energy subsidies. Congress allocates budgets, and those expenditures for renewable energy were tens of billions per year.
“A 2017 study by the consulting firm Management Information Services, Inc. (MISI) estimated the total historical federal subsidies for various energy sources over the years 1950–2016. … The MISI report found that non-hydro renewable energy (primarily wind and solar) benefited from $158 billion in federal subsidies, or 16% of the total, largely in the form of tax policy and direct federal expenditures on research and development (R&D).” (Wikipedia)
That’s less than the cost of the Iraq for 2008 only, or 2007 only, with rather more to show for it.
Even Solyndra, held up as an example of government givaway to the industry, only cost about taxpayers about 535 million.
Just because it’s small beans compared to something worse, doesn’t mean it isn’t bad.
You have bigger things to worry about than Obama. The Trump is effectively sinking your ship with all hands aboard.
No, people like you are trying to sink the ship with no regard for the people aboard (including you). What was your post supposed to accomplish exactly? Why not actually make an argument that you can back up? What does your obsession with someone have to do with solar panels?
Use of micro-inverters (or the less efficient power optimizers) and parallel wired systems have a lot less susceptibility to the hot spot issue since each panel is a unit unto itself and cannot back-feed weaker panels.
Yes, it’s more active components on the roof, but unless you have absolutely uniform sun and extraordinarily well matched panels with nearly identical wear conditions, it can seriously improve your performance and reduce the hazards mentioned above. It has the added advantage of also providing much greater visibility into the performance of your system for proactive maintenance as you can now monitor and trend the performance of each individual panel rather than looking at the overall results from a string of panels.
They also suffer from bad qc in the stray radio emissions department and make every ham operator angry
Can’t you shield the inverters? …or am I missing something important?
That’s generalized statement – which model and brands are you referring to? I have seen the EMC reports for the units I have on my roof, and my spectrum is good for ham activities with the roof system on or off.
KB6MER and I’ve got no problems with the 31 units on my roof causing interference.
High-quality solar panels have a bypass diode on every solar cell in the panel. This really should be an electrical code safety requirement.
‘Super barrier’ diodes are often designed specifically for this purpose.
Active bypass via a controlled MOSFET is also possible, but much more rare because of the increased complexity and cost.
Shading, leaves, bird droppings, other debris, etc., can lead to an under-performing cell that will create a ‘hotspot’. The larger the panel, the higher the current, the more the heating potential.
Satellite-grade panels have bypass diodes on each cell.
Commercial panels have bypass diodes on each group, typically 18 to 24 cells per group. Reverse voltage limits on the bypass diodes versus the open circuit voltage of the cell group that is being protected determines the count of the cells in the group.
Failure of a bypass diode could easily allow a group of cells to overheat, if they were shaded and being reverse-biased by the rest of the circuit.
It warms my heart to see people on a site dedicated to technology bashing technological advances.
Do you know how many accidents happen at fossil fuel related industries on a daily basis? No? None one does… Because It got to the point decades ago that unless there is a major explosion or multiple fatalities that make the news, no one is going to hear about it because when it happens every single day it because routine and routine doesn’t make headlines.
New fancy solar cells that have the promise to free us all from the tyranny of the fossil fuel cartels – any problems get major attention. This technology will only advance, get cheaper and spread, as will storage technology and the guys that make their money off of selling the world liquified dinosaur bones are terrified. And even though there will still be a need for the stuff for some plastics and processes for other chemicals, the lions share of their cash comes from energy – So they .
I personally can’t stand Elon, and think he’s about half nuts, but he at least realizes you can either get in on the ground floor of this and be a leader or you can be left behind…
The irony of complaining about “fossil fuel cartels”, while 80-90% of the world market of solar panels comes from China where they are manufactured using cheap coal power in total disregard of environmental pollution, and the cobalt in batteries comes from conflict mines in Congo, lithium comes from Bolivia… etc.
China has a higher percentage of coal generating plants with emissions reduction technology than the US. if you don’t think that some kind of oil cartel is in place, then why is the US so kiss-a$$ with the Saudis?
Deaths per terawatt-hour of generated power (2018):
Nat. gas 4,000
Rooftop solar 440
The US out-produces the Saudis and is an exporter now. “Kiss-ass” with the Saudis is about the Gulf and commerce on the seas and the insane intent of Iran’s leadership (and Putin, their puppet master). There is no need for mysterious cartels when you have bad guys right out in the open. And “higher percentage” of reduced emission plants is meaningless. How many are there? How much do the pollute? Solar City is a region outside Guangzhou that was a show-place of the future and is now a ghost town. There is a surplus of manufacturing ability which keeps prices low. Affordability is an illusion.
Such a good point Luke, specially considering how the biggest oil producing countries (especially Saudi Arabia) are really famous for their green power generation, that no oil comes from conflict zones and that oil is collected by hunter gatherers and used as the nature gives us without any major extractive operations or industrial refining processes between the oil and you.
Making a tu-quoque argument is simply admitting your own fault and pretending that two wrongs make a right.
And using fossil fuels to produce 80% (14% being coal ) to produce your energy is somehow less environmentally detrimental ?
No, I don’t know how many accidents there are at fossil fuel power plants.
But I do know that any of these accidents will be contained on-site, they have emergency measure in place, and they’re not setting fire to anyone’s roofs.
That’s kinda the issue here.
Do a Google image search of solar panel fire.
It’s not a rare thing at all and likely to be greatly under-reported.
Top pic, especially cut off, kinda real looks like the TTs
Yes, same thought. Initially I thought it was crass and offensive. But that was 19 years ago. Some of these folks were not even born yet. Like Boomers and WWII. Our parents lived it and for us it was ancient history.
Funny this hasn’t come up before. There was a small company in Colorado called Abound solar, which received 400 million dollars in Department of Energy loans. They had a very similar issue: The panels kept catching fire. They eventually closed their doors, (and didn’t pay back the 400 million), and left Colorado a small Super-Fund site with all the excess toxic chemicals they abandoned.
Solar may be a great alternative energy source, but don’t think for a minute all the byproducts are green!
The main pollution form solar panel manufacture are:
a) Gasses that evaporate off of the solvents used to clean silicon wafers and the assembled panels. These are supposed to be captured and processed, but China is now emitting tons and tons of the stuff, essentially reversing the closing of the ozone hole since the ban on CFC gasses.
b) Silicon tetrachloride, which is the leftover solution from etching silicon wafers. This is supposed to be recycled back to Silicon, but the process takes a ton of energy and money, so Chinese manufacturers dump the stuff around the countryside. When water hits the dump, it undergoes a chemical reaction which releases hydrochloric acid. When it’s dry, it kicks up as dust clouds and burns peoples lungs.
c) Metallurgical grade silicon is refined using a reduction reaction with carbon. Production of solar panel grade silicon emits tons of CO2 which comes from fossil sources.
All of this could in theory be done in an environmentally responsible way, but then you wouldn’t be able to buy solar panels at 30 cents per Watt.
“Silicon tetrachloride, which is the leftover solution from etching silicon wafers. This is supposed to be recycled back to Silicon, but the process takes a ton of energy and money, so Chinese manufacturers dump the stuff around the countryside. When water hits the dump, it undergoes a chemical reaction which releases hydrochloric acid. When it’s dry, it kicks up as dust clouds and burns peoples lungs.”…
This doesn’t sound right at all. It can’t take a ton of energy and money if it readily reacts with water and produces hydrochloric acid. All you need to do to scrub the hydrochloric acid is react it with limestone. They do that now to scrub sulphur dioxide from power station exhaust.
“All you have to…”
Yes, but what you’re describing isn’t a closed loop process. and reacting HCl with CaCO3 releases CO2.
Besides, if you do deliberately react the silicon tetrachloride with water, you get silicon dioxide, which is more difficult to refine back to silicon. Instead, they put it in a galvanic cell and electrolyse the silicon out onto a titanium sheet, where it can be recovered. China now “mandates” 98.5% recycling rate, but the investment and running costs for the equipment are high.
Silicon tetrachloride, when purified of other contaminants, can be used for making ultra-pure silicate glass which is used for optical fibers, so there’s actually a demand for it.
Yes, the byproduct is bad, but the idea of solar is you only produce those bad byproducts once per panel per 10 years. Burning coal and fossil fuels is constant. It’s a part of every manufacturing operation. If you can convert these manufacturing operations completely to solar, you ween off one by one the effects of green house emissions.
Yeah, but nobody’s suggesting burning coal as an “alternative” to solar panels. The competition is nuclear, wind, geothermal, biogas… etc.
The real problem is that most solar panels have a plastic backing sheet that is flammable.
Even with the best quality installations (not you Tesla) and regular maintainence it is always possible for a bad connection to cause a huge DC arc .
The backing sheet catches fire and drops blobs of blazing goop spreading the fire to adjacent panels.
This is an inconvenient truth that infuriates the Green Fanatics.
How DARE I even suggest such a thing?
Interestingly, the solar panels at a nearby Tesla charging parking lot are glass backed. Weird seeing through between the cells, also, I would think they be slightly less efficient due to loss of the small amount of reflected light.
I remember seeing, years ago, a company that makes aluminum water cooling panels to fit behind regular panels, increasing efficiency. Would think something like that could dramatically mitigate fire risk. I’d considered them, but didn’t have any way to use the waste heat. Surely a larger company with limitless* resources could find a use for it, evaporation cycle cooling or something.
Found it: sundrumsolar.com
Hi. someone give me a panel that as an hotspot but the real problem was that under some shade the reverse diode get very hot and melted the connexion box and the diode are in short-circuit. so i things the diode are not enought cooled and makes the hotspot on the top.
Why not look up the facts instead of pitting your guesswork against unverified forum post? It’d literally take ten minutes to educate yourself. de Bruijin’s claims are independently verifiable.
“The idea that a subsidy will kickstart a technology is patently false”
The Internet never happened. We are actually sending these messages through free market telepathy, yo.
The internet existed before the government subsidized a bunch of backhaul cable.
Also, thanks to the US and ARPANET, and Gore, the structure of the internet in terms of names and addresses is centralized and controlled through IANA and ICANN, which to this date gives the US a tremendous influence over how the internet works and who gets to be on it.
Meanwhile, the early competition, such as FidoNET, were decentralized and they didn’t have the scaling issues like running out of IP numbers, or having a global routing table that is slowly growing beyond anyone’s ability to process it.
It’s completely tone deaf to try to defend A VENDOR who convinced a CUSTOMER to install a piece of equipment on 250 buildings, and then had a half dozen of those pieces of equipment CATCH ON FIRE. Leave out the names of the vendor and the customer. Leave out your particular opinion on the politics of Solar power and the relative moral righteousness of either party. If I bought 250 hair dryers. and 4 of them started fires in my home or business – I would be perfectly justified in my complaints against the vendor. That these hair dryers were built by Mother Theresa or by the Mafia would have little to do with the veracity of my complaint.
I seriously doubt that 4 out of ANY other 250 buildings one could choose, had electrical fires during the same period of time. It’s a smokescreen to day they didn’t keep the roof clean, or they should have done this or that. If Solar has even a 1% annual rate of starting structure fires without exotic maintenance then it is totally NOT ready for prime time! Any meager carbon reductions that result are going to be offset by the smoke from the fires, and the cost of building all the extra fire stations and buying all the extra fire trucks that this “green” technology requires.
The solar industry HAS to be held to the same standards as anyone else – or it’s all just smoke and mirrors.
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