Is cracked silicon a defect that should be covered under the Product Warranty? Or is a crack only a defect if if affects performance?
When it comes to solar panel manufacturers, SunPower is basically royalty. At 33 years old I can’t think of any solar panel focused company that’s survived longer. It was founded in 1985 by Richard Swanson who is a solar panel genius. By that I mean he’s been an important figure in field of solar photovoltaics and not that he’s a talking solar panel or something.
A solar panel genius.
When it comes to solar panels that go on roofs or in solar farms, SunPower’s are the most efficient in the world. And I do mean in the world. While you can get specialised solar panels with even higher efficiencies, they are often shot into space and so are more out of this world than in it.
While famous for producing high efficiency panels, I’d say SunPower’s main claim to fame is being the first to provide a 25 year product warranty. LG Solar recently matched this but it took them many years to do so1. Australia’s Tindo Solar has also started offering a 25 year product warranty for panels purchased directly from them or through an authorized reseller. A 25 year product warranty is much more impressive and useful than the 25 year performance warranty that is standard in the industry. At the moment the world’s largest solar panel manufacturers2 still only offer a 10 year product warranty.
SunPower was able to provide a 25 year product warranty because they produce high quality panels. If you visit their website you’ll see they are happy to tell you they’re all about quality. They even have a quality statement:
“At SunPower, world-class quality leadership is a top priority. All of our employees share the responsibility to sustain and improve product quality and services for our customers – internal and external. We are committed to achieving world-class quality through operational excellence, continual improvement and satisfying customer needs in everything we do.”
They also have a quote from their CEO, Tom Werner, where he mentions many high quality phrases such as:
“…world class product quality and reliability…highest quality products…worthy of our customers’ trust…highest quality standards….continual quality improvement and customer satisfaction…continually improve…world class quality performance.”
Of course all this quality comes at a price and SunPower panels carry a hefty premium over solar panels with less impressive product warranties. But plenty of customers have been willing to pay that premium for the peace of mind a 25 year product warranty provides. But is SunPower’s warranty everything it’s cracked up to be? And are they truly committed to “…satisfying customer needs in everything we do”? Well, the answer to that is — maybe. I’ll tell you about a problem a home owner had and you can decide yourself if SunPower’s response was fair enough or — considering that the home owner paid for top of the line premium panels — should SunPower have handled it differently?
The Problem
They say a picture’s worth a thousand words but these aren’t that great so I think they may only be worth about 300 each:
The dark lines you can see are the result of cracks in SunPower solar cells. Those cracks shouldn’t be there as solar panels are much better off without them. These photos were taken by a home owner and since he may not want me to say who he is I’ll just refer to him as Gary because I think that’s a lovely name. I wanted to name my first child Gary but my wife wouldn’t let me because apparently it’s somehow not suitable for a girl3.
I think it’s likely the cracks were already there when the panels were installed seven years ago in 2011. It’s possible they’ve expanded over time. The solar cells are also kind of brown. This is caused by a reaction between the surface of solar cells and chemicals used to treat the glass. While this looks like it would reduce performance because the panels are less dark than they were and so reflect more light, I have read that losses caused by browning are small and difficult to distinguish from the general slow deterioration that results from age. But the fact a browning reaction hasn’t occurred around the cracks indicates they affect the electrical characteristics of the cell.
Why Cracks Are Bad
Fine cracks in solar cells are usually called either microcracks or hairline cracks. They’re bad because they reduce the performance of panels. One small crack where the silicon on either side remains in close contact has little effect and the reduction in output it causes may not be easily measurable. But multiple cracks result in clear decreases in performance.
Ideally no solar panel should leave the factory with a crack in it. Unfortunately, lower quality panels can come pre-cracked for your inconvenience. Certainly no SunPower panel should leave the factory with a crack in it. Tindo Solar make a big deal about how not one of their panels goes out the door with a crack and if Australians can manage that then Americans — who are like gods to us4 — certainly should be able to.
It is possible for impacts during transport to result in cracks as well as rough handling during installation, such as kneeling or walking on panels. After installation cracks can appear from being flexed in strong winds, especially if they aren’t properly clamped, or from heavy hail. Snow buildup can also cause cracks but that’s usually not a problem in Australia.
Cracks may not cause a significant problem at first but they can get worse over time. Solar panels expand when they warm up and contract when they cool down. This thermal expansion and contraction can gradually cause cracks to lengthen and expand and over time can damage electrical contacts. In severe cases this can lead to the entire panel failing. This means cracks that cause no real problem now can, years later, result in a solar panel with poor output that drags down the performance of your system.
SunPower panels have a copper backing that will, hopefully, limit damage from thermal expansion. But looking at the thermal expansion coefficients for copper and silicon I see they are:
- Copper: 16.6 microns per meter per degree of temperature change
- Silicon: 3 microns per meter per degree of temperature change
This means they expand and contract at different rates. This fact in of itself is not a disaster but it does mean any cracks will have stress placed upon them due to temperature changes and have the potential to worsen.
On the bright side, I have personally mangled a SunPower solar cell with my hands and it held together much better than other solar cells I’ve crushed in my paws. Hopefully that indicates they are good at resisting further damage after being cracked.
Cracks are very common. One study of 45 older panels in 2017 found that 84% of them had at least one crack. But none of the tested panels were made by SunPower.
SunPower’s Warranty
The SunPower warranty for their X and E series panels can be found here. It states:
Looking at that I see they mention defects here:
“…shall be free from defects in materials and workmanship under normal application, installation, use and service conditions…”
Since a crack is clearly a defect they should be covered by the warranty. However, the warranty also says:
“Subject at all times to the terms and conditions as set out in this Limited Warranty…”
Looking through the rest of the warranty for terms and conditions that could apply I find this:
This says the warranty does not apply to the browning of the solar cells provided it doesn’t cause the the output of the panel to drop below the minimum the warranty allows. It also leaves it open for SunPower to say cracks are cosmetic and the warranty does not apply unless they cause the power output to fall below the warranted minimum.
SunPower’s Initial Response
When “Gary” informed his solar installation company about the cracked panels, they in turn contacted SunPower. Sunpower did not offer to replace them under warranty due to their having defects. Instead they said:
“this kind of cell crack has no effect on module performance and this is not valid for warranty claim unless it cause [sic] a performance issue.”
They also said they were not prepared to cover the cost of the solar installation company going to Gary’s house and testing the performance of the panels:
“Please be advised that we do not provide our standard compensation nor payment for initial site visit. We only provide payment once the issue has been validated and we authorize a repair/ replacement of the product.”
The solar installation company didn’t fancy going to the effort of testing Gary’s solar panels and implied to Gary that was the end of the matter.
Gary then sent an email to the SolarQuotes helpdesk5 and we contacted Sunpower on Gary’s behalf.
Sunpower suddenly changed their tune. They contacted Gary and promised to investigate his solar panels’ performance to determine if it had fallen below the warranted minimum. So they were still treating the cracks as a cosmetic problem rather than a defect but at least they were prepare to investigate the panels’ performance. While I waited for the situation to develop I had a chat with a solar expert about the problem.
A Solar Expert Responds
I had the privilege of being able to interview solar industry expert Finn Peacock, owner of SolarQuotes and author of The Good Solar Guide on this topic. Full disclosure — he is my boss.
ME: Thank you for agreeing to speak to me on this topic, Mr Peacock.
FINN: You know I’m not really here, right? This is just you paraphrasing what I said in a casual conversation we had on the topic.
ME: Shhhhh! You’re ruining it!
FINN: All right, we’ll play it your way. Go ahead and “interview” me.
ME: In your opinion how should SunPower have responded when Gary informed them about the cracked cells in the solar panels?
FINN: SunPower produces premium panels. They cost Gary a lot of money, particularly at the time he had them installed, 7 years ago. His installer was paid to provide a premium system and was obligated to give it to him. While cracks can develop after installation, high quality solar panels should be resistant to this. Because of their expense and the statements SunPower has made about delivering high quality products, their panels should be held to a higher standard than cheaper ones. For this reason, in my opinion, SunPower should have regarded the cracked solar panels as a defect and replaced them under their product warranty regardless of whether or not their output is high enough for them to meet their performance warranty. But at the very least they should have agreed to get the panels tested when Gary sent them the photos – not fobbed him off. It shouldn’t take the World’s Greatest Solar Website™ to step in to get SunPower to do the right thing.
And secondly – Gary’s installer should not have passed the buck to SunPower. Under Australian Consumer Law, the company that took Gary’s money is responsible for all express and implied warranties no matter how the manufacturer responds. In my opinion, his solar company should have gone and tested Gary’s panels for him whether SunPower were going to compensate them or not.
ME: Thank you for your time. Are there any remarks you’d like to make in closing?
FINN: Nothing on SunPower, but I would like to say that Ronald is one of the most talented bloggers of our age. He’s also an all round great guy whose personal finances in no way resemble a dumpster fire. If you’re an unattached woman you should definitely take him out to dinner. He says he’s certain he knows what he did wrong in his previous three marriages and will probably stop doing it. Be sure not to miss out on this great catch, ladies!
SunPower Replaces The Panels Under Their Performance Warranty
After SolarQuotes stepped in SunPower asked Gary to send them information on his solar power system’s performance and after receiving it decided to replace the panels at no cost to Gary, not because they were defective but because they failed to meet their performance warranty. Interestingly, and to SunPower’s credit, they accepted the information Gary gave them and did not require them to be tested.
It is clear that if your SunPower solar panels do not meet the standard required by their performance warranty then SunPower will replace them. However, given that they are high quality premium panels that cost significantly more than the average panel, perhaps SunPower should have immediately replaced the cracked panels because they were defective without first checking to see if their performance was acceptable. Finn Peacock thinks they should have but SunPower apparently doesn’t.
How Would I Respond?
Personally, if I discovered my solar panels had cracks in them I wouldn’t be happy about it regardless of what type they were. But I would be particularly upset if I had paid good money to get what are supposed to be among the highest quality panels available. On the other hand, if I was confident their output was still above the minimum they were warranted for, I probably wouldn’t be too worried.
However, I do tend to be easy going and in the habit of accepting things that are good enough rather than actually good. That’s how I ended up marrying my first wife. Oddly enough, she didn’t appreciate this personal trait of mine and was always telling me to grow some balls. And eventually I did. Here’s photographic evidence:
Footnotes
- Solarwatt offers a 30 year product warranty but it appears to have some conditions attached that I will tell you about as soon as I learn to read German. ↩
- In 2017 the world’s four largest panel manufacturers in order were Jinko, Trina, Canadian Solar, and JA Solar. ↩
- It’s a terrible thing to realise you’ve married a sexist. ↩
- American gods who employ Philippine and now Chinese citizens for their workforce, but that’s okay. Even Zeus didn’t do everything himself. ↩
- Gary was not referred to his solar installer through SolarQuotes® and the installer is not in the SolarQuotes® network – but we are happy to help anyone with a solar problem ↩
About Ronald Brakels
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Good article but some doesn’t make sense in the early part.
E.g
At the moment the world’s largest solar panel manufacturers2 still only offer a 10 year performance warranty……is that meant to be product warranty??
SunPower was able to provide a 25 year performance warranty because they produce high quality panels. …..Is that meant to be product warranty??
Oops! That’s embarrassing! I did get performance and product mixed up there. Fixed now. Thank you for pointing that out.
Still laffin’… . 🙂
Lessor
LA
Hi Ronald,
Loved your article. Your funny!
I am considering installing solar for my home. There are so many companies. And There is the thing with Solar scams.
Can you please guide me deciding who to go with, which panels and inverter at a cost effective price.
Hi Ash
If you use our service you will receive quotes from reliable installers who do quality work. My boss, Finn, goes to a lot of trouble to ensure we will only ever put you in touch with trustworthy installers. Just go to our homepage here:
https://www.solarquotes.com.au/
And enter you postcode at the upper right of the page. Then answer the questions it asks as best you can. If you have any questions about the quotes you receive let me know.
Solar Quotes gives you good information on products and great general information on solar.
Solar Quotes is great ,however, as far as Installers go they pay Solar Quotes for their “Leads” and the recommended installers in your area are such people. You need to independently verify their “qualification” to do the job.
That is not to say Solar Quotes aren’t sincerely recommending people who they believe will do a good job. Fact is though Solar Quotes does not do “thorough” vetting of those who pay them and I know because I worked for one until I found out from bitter experience they severely let clients down.
After six years in the business I would say to you and anyone else, the installer is the most critical part as poor installation is the number one cause of solar system failure. This assumes you are getting at least reasonable products.
The key points to note are:
Many solar companies are just marketing companies who sub contract the install to someone else. This is risky because more often than not they sub contract to the lowest bidder who is getting a set price for the install and will do the job as quickly as possible and move on to the next job. If anything goes wrong you won’t see them again and you are on the phone to the marketing company who probably will struggle to find or pay for someone to fix it.
The industry is still young and somewhat immature. On the coastal areas there is a sort of price war where sellers mistakenly believe price is the only factor. Trouble with this is it leads to corner cutting (Often in concert with cheap and not so good products). I have an Energex Electrician as a client who sees solar installs all the time that are substandard. He has seen first hand a vast number where, worst of all, the wiring from the inverter to the switch board is undersized and it overheats and catches on fire!!! This is the extent of the corner cutting.
Misleading product references,especially Tier One. This is a finance rating not a product endorsement. There are many Tier One panel manufacturers but the difference in quality is enormous. Some tier one products are very fragile and will not withstand the elements. I have personally walked on Tier One Panels and immediately ruined them , not realising they would be so incredibly weak ,having been used to others that can take a four wheel drive being driven onto them.
Most people don’t realise the number on threat to a solar panel is the sun! They convert light to electricity but heat is the enemy. The difference between a good panel and a poor one is its heat handling ability. In Australia ,especially the further north you go the more important this becomes. I have seen testing of 13 panel brands, all claiming to be Anti PID (Potential Induce Degradtion) basically leaking due to heat as electrons jump to the frame and out to the atmosphere rather than going to the inverter. Of the 13 only 4 actually were anti PID. I have also seen testing showing a poor quality panel leaking by up to 90% brand new on a hot day! Just when its a perfect sunny day they stop working??
So, in summary
1. Are you dealing direct with the actual installer? An electrician owned company who takes pride in their work and can demonstrate that quality of workmanship is the safest bet.
2. Paying too little will almost certainly lead to dissappointment and compromised long term results.
3. Choose quality products as they will be cheaper (from better results) in the long run. For the difference in price the premium products (on Solar Quotes Scale) offer, in my opinion, the best overall value for money.
I know you didn’t ask for my opinion, however, I wish you to succeed with your solar experience!
Hi Ray,
Thanks for the comment. We do vet (and then monitor) the companies we refer thoroughly.
Please could you let me know which company you had issues with – either reply to this comment or email me ([email protected]) and I’ll investigate.
Best Regards,
Finn
Hi Finn,
The company in question was Cleanswitch. The issues that surfaced mainly related to not actually obtaining approval to connect to the grid before install, some taking up to a year to resolve…. I too thought that your vetting meant he was a sound operator.
I have nothing against what you do, however, I stand by my comments and recommend anyone to investigate the installer/seller to be sure who is doing the job and satisfy themselves as to the qualification, quality of work and ability to provide sound technical support if and when needed.
Thanks for you interest. I have some other information about a new solar program you may be interested in to run a story on. Email me and perhaps we can arrange a discussion.
Regards
Ray Havill
Hi Ray,
If what you say is true (and I have no reason to doubt you), then it sounds like I messed up and our vetting didn’t work in that case. I apologise. Cleanswitch were a client for about 3 months in early 2017. Our vetting improves all the time, and I’m very confident in our current stable of installers.
Finn
Hi Finn, I would like to supply some feedback on your three free solar quotes.
After filling in my details I was only supplied with details of two companies. One was Westside Energy – I never heard from them, and the other was NRG Solar – fantastic salesman who took the time to visit my location and chat with me.
I have been investigating solar now for a couple of years and after convincing my husband, we are going ahead with it, we are in process of doing the paperwork. My only thing I would like to add, as I haven’t been made aware of it here (may not be relevant?) or from any sales persons, but feeding back into the grid is solely dependent on the capacity of the transformer you get your power from.
I was not made aware of this during my investigations but found out only last week by chatting to my neighbours who are getting a large system and they were told they were limited on how much they can feed in. I spoke to my sales guy who, without hesitation, confirmed that what neighbours said was correct and that no, we can’t feed back in as our transformer is full. To double check, I rang Powercor and they confirmed this. Only 30% of a transformers capacity (i.e. 25kVa) is allocated for solar power feed in.
Bummer, but we are still going ahead and hopefully, be able to afford a battery in a few years to compensate.
And I am so glad I read this whole article for the funny laughs!
If I wasn’t happily married and living in Victoria, I would ask you out Robert 🙂
Hi Guy’s,
Regarding the warranty issue with Sunpower panels.
How many cases have you come across with Sunpower warranty claims.
Reason for my concern is I am due to have a system installed this week.
Cheers Barry
Australia
Hi Barry
SunPower panels aren’t perfect, but they should be more perfect than most panels out there. While I am aware of some SunPower panel failures it’s not really possible to say if they are more or less reliable than other premium panels. Because they’ve been around longer it’s reasonable to expect them to have more failures even if they are the most reliable. So while it is possible you will be unlucky and have a problem I think the chances are very good that all your SunPower panels will last for their full 25 year product warranty without a problem.
Hi Finn Peacock,
Re – cracks in panels ( regardless of brand). Cracks in transit should they be checked onsite by the installer prior install?? Or if the installer is on a contract price to do the job for a fixed price , even if he/ she sees a crack/ s are they going to let on With no spares on site it’s going to muck with their time and profit margin, so install them anyway / get paid and move onto next job?? Would it pay to organize an independent person / tradesmen/ electrician to check them over same day of install or very next day?? Even if it meant paying for that service. At least that way ,you know from the very start if the panels are good or defective Have you addressed this in previous emails?
Hi Glenn, Ronald here.
Tiny cracks can’t be readily detected without special equipment so it’s not really practical to check on site. But no reputable installer will want to install a panel they know is damaged. If they take your money they have a responsibility to provide you with a properly functioning solar system. If they don’t they have to come back and fix it. Unfortunately, disreputable installers may have no problem installing a panel they know is damaged or installing crap panels they are fully aware may fall apart within a few years. So it definitely pays to do your research and pick a good installer and not just buy based on price. You are also protected by the panel’s performance and product warranties and Australian Consumer Guarantees. The difficult part is knowing if you have a problem. Good installers will generally provide you with an estimate of how much your system will generate and you can take action if it falls too far from this. If you are concerned then investing in a good quality monitoring system can help detect problems.
Hi Ronald,
1) By ” good quality monitoring system….to detect problems”, do you mean micro-inverters which allow individual panel monitoring? How do go about that if you have already installed a central inverter like Fronius?
2) With 25 years warranty, how does LG and Tindo compare to Sunpower in terms of performance, price and warranty claim experience?
Regards
Individual panel monitoring is the best, but hard to get without microinverters + reliable monitoring or optimizers + reliable monitoring. If you want individual panel monitoring on an existing string system the best way might be to install suitable optimizers that support good quality monitoring. But your system would either have to suffer from considerable shade issues or you’d have to be really keen on individual panel monitoring for the cost to be worthwhile.
You can compare prices and warranty periods on our solar panel comparison chart:
https://www.solarquotes.com.au/panels/comparison/compare-solar-panels/
Tindo has some conditions on their 25 year product warranty and that’s why it is still given as 12 years on the table. I would expect and hope that LG, Tindo, and SunPower would all have excellent responses to warranty claims.
Sunpower warranty is illegal, a munafucturer/supplier cannot say a warranty is subject to the conditions of their limited warrnty.
Statutatory warranties override manufacturers/suppliers limited warranties,
And as you say the installer is responsible for warranty, they cannot refer you to their suppliers.
I dont understand why so many Australian companies still dont know consumer law.
Con, – not quite true
for example Statutory warranties also have a time limit and also often exceed the minimum 1yr all products get…. in the case of Solar panels, lets assume more than 1 yr, but ACCC and industry may agree 8yrs is a good yard stick for statutory term, (excluding what the different manufacturer has for this argument) anything given by a manufacturer, past that CAN have conditions and terms that they dictate.
Statutory warranties exceed the minimum 1yr under conditions too, like cost vrs how long something “should” last
an actioncam costing $1000 might still only have 1yr
where as a $1000 tv should last 2-3 yrs
Hi Legend,
Can you please update the SUNPOWER info because it is about 5 to 10 years old on the warranty. I also heard they replaced the whole system and have and how did you get these photos . Also could you please compare this to other claims on the warranty. Is this a general problem with SUNPOWER panels. I have also heard more stories about other panels and cracks.
Appreciate your help on the mater
Christine not much if anything has changed with the Sunpower warranty since this article was first written. In particular b) under the clause 4. Exclusions and Limitations referenced in this article remains as of this time.
I’m also considering getting Sunpower panels though personally I am not overly concerned. In the hopefully unlikely event of said degradation occuring and Sunpower (or any other manufacturer for that matter) treating me like they did Gary the first time then I may use the stick of starting a Whirlpool thread on the experience or highlighting it on a blog etc.
As Ronald has stated in the comments field it would be hard to determine if they are any more or less reliable than other premium panels (probably impossible given limited data available). IMO Sunpower is highly regarded and as with every product there will always be complaints and incidences of poor service.