Clean Power

Published on October 19th, 2015 | by Derek Markham

126

How Long Will Solar Panels Last?

October 19th, 2015 by  

Originally published on Cost of Solar.

When considering going solar, we know that one of the top questions tends to be something along the lines of “How much do solar panels cost?” or “What is the cost of solar?” because for many of us, adding a home solar array isn’t just about reducing pollution and greenhouse gas emissions, but it’s also about the bottom line, which inevitably comes down to discussions of dollars and cents.

Is home solar worth it?Once it’s established that the cost of going solar isn’t nearly as high as people might think, and that a home solar system is well within reach of many homeowners, a popular follow-up question is usually about longevity and reliability, or to phrase it explicitly, “How long do solar panels last?

Most solar panels used in home solar arrays come with a warranty for some 25 or 30 years, which means that the solar panels are guaranteed for decades, unlike many of the other goods we buy. And again unlike many other consumer goods, they don’t ‘give up the ghost’ at the end of their warranty period and need to be replaced, but continue to still produce clean electricity, although at a slightly less efficiency each year. In fact, some decidedly old-school solar cells have been producing electricity daily for about 40 years or so, and are expected to continue to power homes and businesses for decades more.

According to a study undertaken by the National Renewable Energy Laboratory (NREL) a few years ago, which looked at the ‘photovoltaic degradation’ rates of some 2000 solar installations, the average solar panel loses about half of a percentage point (0.5%) of efficiency per year, which means that a panel at the end of its 25-year warranty period should still be operating at about 88% of its original capacity. However, not every panel will see degradation rates as high as 0.5%, as shown by this 30+ year old solar panel, which outperforms its original specs, even after decades in the sun.

This decades-long life of solar panels makes the economics of going solar even better, as most systems will pay for themselves within the first ten years, and yet still produce many many more years of clean electricity for their owners, so asking “How long do solar panels last?” might be the wrong question.

Perhaps a far better question might be “What are the estimated maintenance or replacement costs for a solar energy system?”, because while the solar panels themselves probably won’t need replacing anytime soon, the inverter (which converts the DC from the panels into AC for feeding into the home’s outlets and the grid) may need to be. The average inverter warranty ranges from 10 to 15 years, and unlike solar panels, will not just slowly get more inefficient, but will instead just quit working. However, while that’s usually the case with a central inverter (which handles the output of all the panels), a newer type, the so-called ‘micro-inverters’, are installed or included with each solar panel, and are said to have a much longer lifespan (up to 25 years), and could last for decades as well.

Even adding in the cost of a replacement inverter (or several, if micro-inverters are used instead) over the life of a solar energy system, the return on investment for solar is still better than many places you can put your money, and has the added benefit of essentially locking in your electricity prices for years to come.

Reprinted with permission.


Buy a cool T-shirt in the CleanTechnica store!

Keep up to date with all the hottest cleantech news by subscribing to our (free) cleantech daily newsletter or weekly newsletter, or keep an eye on sector-specific news by getting our (also free) solar energy newsletter, electric vehicle newsletter, or wind energy newsletter.

Tags:


About the Author

lives in southwestern New Mexico and digs bicycles, simple living, organic gardening, sustainable lifestyle design, slacklining, bouldering, and permaculture. He loves good food, with fresh roasted chiles at the top of his list of favorites. Catch up with Derek on Twitter, RebelMouse, Google+, or at his natural parenting site, Natural Papa!



  • Ivor O’Connor

    When was the PV installed and over what period did the Enphase micro inverters fail?

  • mike_dyke

    I wasn’t saying that they weren’t compatible but as far as I know, batteries work on DC and if you have to attach them to AC you need a converter.
    If that converter is inside the box, then fair enough.

    That battery system “… was built on Enphase’s new S-Series microinverter platform” therefore it has a converter in it.

  • mike_dyke

    Powerwalls work on the DC side of the panel

    The panels on my system are on the roof (2 stories), so to replace one of those will need ladders/scaffolding/good weather.
    The inverter is in the loft, so a problem with that just means going up inside stairs.

    • NRG4All

      What happens if you don’t have solar panels but want to use the power wall for trimming peak period utility usage, or for back up during power failure? I understand that you have to buy an inverter in that case. I suppose you are right in that it would be more efficient to charge the Powerwall directly from a DC source, but it would not be impossible to use it without PV.

      • mike_dyke

        Yes, you would need an inverter or you might get away with a DC to AC converter which normally forms part of the inverter. The DC to AC converter handles synchronisation with the grid so that the AC output doesn’t cause problems further down the grid (e.g. correct voltage/phase)

        This is the “DC to AC converter” which is not supplied with the Powerwall.

        Other storage solutions have the converter built in but can’t handle PV panels

  • Richard Poore

    Even if newer thin film solar panels do not have the life span of older tech solar panels it doesnt really matter. Solar panels will easily pay for themselves in less than half the time of most warranties. And if panels do start failing in the 15-20 year time frame, we should be able to replace them with more efficient panels anyway.

    More extreme weather areas it may be more of a factor of course. As solar panels are changed we will especially need to consider their vulnerability to extremes of cold plus snow, but that should already be a consideration when installing a system now.

    There should be a growing market for used solar panels as well. Less efficient or slightly damaged panels will still find users.

  • vensonata

    Remember that inverter replacements after 15 years will be with an inverter that costs about 7cents watt. 5 kw for $350. So don’t extrapolate from today’s costs. Those inverters of the future ( two years from now) will be anywhere from 90% smaller (google little box inverter winner) up to 50% smaller (the new solaredge HD inverter arriving this year). Reliability will increase. Efficiency will increase…the New Solaredge inverter is 99% efficient. Batteries will also start figuring in to this system longevity calculation. It is now possible to arrange a lithium battery bank, (of various chemistries including lifepo4 etc.) that will last 30 years when most of its cycling will be at less than 50%. This formula gives two full days of storage, which only occasionally be needed.

    • Ronald Brakels

      While smaller inverters might not seem that much of an advantage to people who already have a usual sized one, smaller inverters means they could have some energy storage built in while keeping the overall size the same as the old inverter it is replacing. The storage might only be a couple of kilowatt-hours, but even a small amount is very useful to have.

      • mike_dyke
        • Ronald Brakels

          Yep, I might even look into something like that for a friend who is building a new house in Queensland and is running afoul of restrictions on the amount of PV she can install. But I was specifically referring to how if a new inverter plus battery storage is the same weight as the old inverter, it makes installing energy storage extremely easy if and when the old inverter fails. One just unplugs and unbolts the old one and then bolts and plugs in the new one with storage using the old mount. Simple. (Note: Not quite that simple.)

          • mike_dyke

            That product was produced before 2013 and is probably outdated nowadays (although still on sale). That google competition to get much smaller inverters is due to be completed in January, so there could be a lot of next-geneation products coming shortly. If you include the new lighter/smaller battery packs as well which we keep hearing about, then it’s looking like you might be able to do your “replace inverter with new inverter+storage for the same weight” idea.

          • Ronald Brakels

            Eleven thousand Australian dollarydoos according to a quick internet search. It’s enough to make one wait for the Powerwall.

          • mike_dyke

            Yes – I wonder how much the powerwall will have improved by the time we are able to buy it?

          • Ronald Brakels

            We are supposed to be getting some in Australia this year, around about now, but I don’t think I’ll be able to get my hands on one in the short term.

    • Ivor O’Connor

      Is the SolarEdge inverter 99% efficient or is the mppt 99% efficient and the inverter it goes to 96% efficient?

  • Quiet_Think

    It would be helpful if the author explained the factors that determine aging differences. It would be helpful to know if panels exposed to lower insolation last longer than those exposed to higher insolation. Also, historical lifetime differences of both mono-crystalline and poly-crystalline panels. Then, one could better predict their expected lifespan based on their local conditions and product choice.

    • Bob_Wallace

      According to the NREL paper high UV and snow/wind loading results in panels losing output (up to 0.4% a year) as opposed to panels in low UV, low load flexing environments (0.1%).

      http://www.nrel.gov/docs/fy12osti/51664.pdf

      I can also report that failing to use a lock washer on one leg of a rack in a high wind installation can result in result in output to drop by 100% overnight.

      • Quiet_Think

        Thanks for the link. I quick glance through, it appears the study is very inconclusive regarding UV impacts, says more work needs to be done.

      • AU_Battery

        Many of the reference data NREL reported on don’t show the accurate profiles of the missing solar panels in case studies, neither report on the findings of the failures of the replace solar panels over the reference material.

        It’s not a reliable data it can be depended upon as accurate.

  • JamesWimberley

    The 40-year-old panels still working are all SFIK based on plain vanilla silicon cells. Thin-film hasn’t been going long enough to offer the same assurances. Longevity is the big obstacle to commercialization of perovskite cells.

    BYD claim that their new all-glass module should have a life of 50 years (link).

  • Richard Otter

    The warranties are great, as well as the measured lifetimes, but are any of the current companies going to be around in 20 years to make good on a defective component?
    That’s what I worry about.

    • jeffhre

      See Bob Wallace comment on insurance companies above.

  • Matt

    Come now you don’t expect a double tracker to last 100-300 years. So I think they left out some maintenance costs. 🙂

    • Riely Rumfort

      Yes some, but if you built it from scratch you can fix it fairly cheap(a sealed couple bearings/gears a decade) the key being to build with minimal moving parts, singles axis if you’re not engineeringly inclined.
      If you choose not to use a tracker that’s also fine if properly positioned and re angled twice a year seasonally.

  • Dag Johansen

    I’m glad to hear that these PV panels last so long. I look forward to my solar PV system giving me plenty of years of service. If my panels degrade and give less power than I need, I can always throw up one or two more new panels to make up for the degradation.

  • Danno

    How would one recycle a panel that is no longer producing well enough to warrant keeping it in service?

    • jeffhre

      By handing them over to someone whose space needs/watt are less intense.

    • Bob_Wallace

      I don’t think there’s a recycling process in place yet. I know it’s been discussed but at this point demand would be too low to justify the effort.

      A long term (20?, 25? years) study reported that they had to replace 2% of the panels over the length of the study. Some delamination problems and some connector problems. I would expect the failure rate lower today with better sealants and sealed junction boxes.

      Disposal? Glass recycles. Aluminum recycles. That’s 80%, 90% of the materials. Sheets of silicon and pieces of thin film material should be inert landfill at worse.

      At some point it will be worth processing out the copper and other (tiny) bits of metal. And perhaps the processed silicon. Maybe the local recycling plant tears the panel apart and mails the silicon to a central recovery plant in an envelope.

      But that’s just for the failed panels. Like jeffhre says, if space is critical replace the old panels with more efficient ones. Pass the less efficient on to someone who has less of a space constraint.

      We don’t know how long panels will last. Forty years looks likely and we don’t know of an age at which solar would stop working. Worst case, a panel produced today is still outputting 84% in 2055 why would you dump it rather than just installing new panels somewhere else? How about the panels that lose only 0.1% per year and are putting out 96% of new?

      • Matt

        Well since likely you will need a new roof in 2055. Maybe you want to donate your panels to the local school or non profit and install those new sexy hyper-dimension panels (wink wink). Got to keep up with the Jones.

        • jeffhre

          You mean the color changing ones, or the regular ones.

        • Steve Grinwis

          My plan involves installing a pile of panels and then having “free” hydro for the rest of my unnaturally long life. So, when I need to replace the roof, I’ll take the panels off, and then put them back up.

          Also: Don’t the panels make the roof last longer anyways?

      • AU_Battery

        Long Term actual studies show missing data.

        In any case it has not been of consistent line of data of actual studies, studies tend to get skewed and a little bit disingenuous on panels which have been replaced over a period of time in studies, panels which have been removed due to failure, linkage bus bars breakdown, fire and so on in the PV.

        • Bob_Wallace

          What studies show missing data?

          How do you know “studies tend to get skewed and a little bit disingenuous on panels which have been replaced over a period of time in studies,”

          Show us some proof of your charges.

          • AU_Battery

            We know that the picture/video above was not fixed for 40 years.

            Do you want to make your case argument about it?.

          • Bob_Wallace

            I have no desire to make a “case argument” about it.

            I furnished you some of the data i have. It seems you have a need to dismiss data that doesn’t fit your preformed opinion.

            I’m not wasting time with you. Have a nice day.

    • AU_Battery

      I would be very concerned anyone propagating that that solar panels running 40 years, I’ve come across various debates around this solar panel whether the panel was kept in storage, or on a shelf for 40 years and only use for test periods.

      There is neither evidence that the solar panel was fixed in place for 40 years.

      • Bob_Wallace

        Here – 35 years installed. Taken down for careful measurement and reinstalled. Now close to 40 years old.

        There is a piece on line about one 30 year old panel that has not been installed bue taken out and tested. Apparently a university teaching aide.

        And here –

        “Kyocera is also one of the few makers of solar modules on the market to possess such long-term studies of its products under real-life conditions. A similar test system is located just outside of Tokyo, Japan and has been in operation for almost 30 years. The most recent measurements, taken five years ago, revealed a degradation of just 9.6 percent. With such real-world data to stand on, Kyocera is confident in offering its customers a 25-year guarantee of 80 percent of nominal output.”

        http://global.kyocera.com/news/2014/0201_komi.html

        • AU_Battery

          That is nice hear, but I would like to see the real data which back their claim.
          The link you gave has no data, but just a one line statement, nothing what you said about this PV module.

          • Bob_Wallace

            That’s the only page I copied. It’s page 9. You can look up the rest.

  • jeffhre

    Food for thought. What’s the warranty on a coal, nuclear, or gas turbine system with distribution facilities? MTBT?

    • Bob_Wallace

      They are guaranteed to work right up to the point they don’t…. ;o)

  • TD1

    The 30 year old panel is interesting and the pioneering customer is very satisfied. However the tests quoted are crude with no incident solar power reference, either from the manufacturer or the owner during the recent tests. There is no way to tell what the yearly degradation rate was.

    Current state of the art PV panel manufacturers tend to under specify performance for insurance purposes, and many customers are likely to be satisfied. To tell the true degradation rate of a specific panel however it would need to be tested at two or more instances in time and under the same test conditions.

  • Bob_Wallace

    ” the average solar panel loses about half of a percentage point (0.5%) of efficiency per year,”

    That’s an outdated study.

    “The National Renewable Energy Laboratory (NREL) performed a meta-analysis of studies that examined the long term degradation rates of various PV panels. They found that the 1% per year rule was somewhat pessimistic for panels made prior to the year 2000, and today’s panels, with better technology and improved manufacturing techniques, have even more stamina than their predecessors. For monocrystalline silicon, the most commonly used panel for commercial and residential PV, the degradation rate is less than 0.5% for panels made before 2000, and less than 0.4% for panels made after 2000. That means that a panel manufactured today should produce 92% of its original power after 20 years, quite a bit higher than the 80% estimated by the 1% rule.

    Crystalline silicon modules located in extreme climates showed high degradation rates. For very cold climates, panels subjected to heavy wind and snow loads suffered the most. On the other hand, panels in similar climates that were installed in a facade, eliminating the snow load, had very low rates of degradation. At the other extreme, panels in desert climates exhibited large decreases in production over time – close to 1% per year – mainly due to high levels of UV exposure. Panels in more moderate climates such as the northern United States had degradation rates as low as 0.2% per year. Those panels could retain 96% of their production capabilities after 20 years.

    Degradation rates are used in solar site assessments in order to estimate the energy production over the life of a system and to calculate the payback period and return on investment. Like everything in engineering, we always assume the worst and hope for the best, so overestimating the degradation rate isn’t necessarily a bad thing. On the other hand, we want realistic estimates so we don’t scare away potential customers who think they’ll need to replace their modules after 25 years. Given the results of NREL’s analysis, it may be beneficial to adjust the rule of thumb so it accounts for the conditions under which the panels will operate.”

    http://www.nrel.gov/docs/fy12osti/51664.pdf

    • Bob_Wallace

      University of Oldenburg

      3.88% total loss over first 35 years. 0.1% per year loss.

      http://www.presse.uni-oldenburg.de/einblicke/54/files/assets/downloads/page0009.pdf

      .

      • Bob_Wallace

        Almost 30 years –

        “Kyocera is also one of the few makers of solar modules on the market to possess such long-term studies of its products under real-life conditions. A similar test system is located just outside of Tokyo, Japan and has been in operation for almost 30 years. The most recent measurements, taken five years ago, revealed a degradation of just 9.6 percent. With such real-world data to stand on, Kyocera is confident in offering its customers a 25-year guarantee of 80 percent of nominal output.”

        http://global.kyocera.com/news/2014/0201_komi.html

        • Ronald Brakels

          Yingli – 80.7% after 25 years. 80%+ seems standard now. Some panels offered only 80% after 20 years, but I don’t know if they are still around.

          • Bob_Wallace

            0.8% per year. There are multiple reports of older panels losing up to 0.8% a year. That’s where the 1% per year thing likely comes from. Then it was dropped to 0.5% and now to between 0.1% and 0.4%.

            Link? I’ll add it to my collection.

          • Ronald Brakels

            Oh, this is a 2 page Yingli PDF: http://www.verengosolar.com/files/YingliWarranty_110922.pdf

            Generally any PV module you get in Australia is going to have a performance warranty similar to this.

          • Bob_Wallace

            Ah, that’s their warranty. I was posting data from installed panels.

          • Riely Rumfort

            My collection lol

          • Bob_Wallace

            You laugh at people who take notes?

            Must be nice to have a perfect memory.

          • Riely Rumfort

            No, no one can memorize all the Urls and charts. We’ll near no one. I was just laughing picturing a collection, like the way one keeps coins or troll dolls. Nevermind..

          • Bob_Wallace

            Google Docs can be your friend, too.

            Look up the page at my comments. All the quotes, images and links are on a single GooDoc page.

          • Riely Rumfort

            A single page is handy with Ctrl+F used.
            Also yes I was a man of few notebooks, cept maybe history courses. I even went textbookless for some courses.

    • Ronald Brakels

      Yep, one thing people should keep in mind is that the performance warranty covers Australian outback conditions. Most people’s panels will be doing far better after 25 years.

    • Ivor O’Connor

      Thanks

    • Dag Johansen

      Well, I hope you are right that today’s panels are better. But I do worry about that . . . often times the way they reduce prices is to cut as many corners as possible without hurting performance. And although cutting corners may end up with panels that provide the same specs, it might be possible that the corners they cut start affecting the longer-term performance. I have no idea if that is true or not in this case.

      But the aluminum cans of soda that I drank as a kid did not break open as easily as these modern thin aluminum cans that easily burst open if you drop them on cement.

      • Riely Rumfort

        Hence why thin films have shorter life spans 8-15 years, I’d say a 120-300 micron wafer with proper encapsulation should do for mono, 200-350 poly.

        • Hans

          Thin film solar cells are not wafers that are cut from a block like regular solar cells. They are condensed from a vapour onto a substrate.

          • Riely Rumfort

            I’m aware they’re CVD(Chemical vapor desposition) I didn’t say otherwise, the same process used for perovskite cells, or graphene before nano-ribbons.
            My point was about the thin cut of Mono and Poly, I’m aware Thin film is CVD only 3-12 microns thick, I don’t think they can even cut that fine with wafers.

        • jeffhre

          Perhaps it is the glass laminate which makes the difference, and not so much the composition of the underlying substrate. After all, when PV fails it has generally been due to a breach of the glass edge seal, not the construction of wafers and wiring.

          • Riely Rumfort

            Thin film will degrade far quicker than thicker mono, a minimum of 80 microns would presumably double the lifespan over TF. Efficiency doesn’t even peak until 50 microns so there’s little point in spending extra on the cutting process to go thinner and a bit thicker(80) for peace of mind to assure longevity seems the least one can do for an attempt at long term production. The Armored wire is basically saying, I don’t want it to require a rewire >50 years from now. Outer wire coatings get stiff and can crack if weathered, so really the amount of wire requiring shielding is rather low as little is exposed to the elements, possibly even just a single output cable from the enclosure.

    • Riely Rumfort

      .2-.5%
      Though it’s notable the high end of this stat is due to Mono-cells intial 9% loss over the first year. Losses become less over time, the panel breaks in much like a shoe, fraying where resistance occurs.

      • Hans

        “Though it’s notable the high end of this stat is due to Mono-cells intial 7-9% loss over the first year or two.”

        I never heard this about monocrystalline solar cells. Are you not confused with amorphous silicon modules? These have an initial degradation that stabilises over time.

        • Riely Rumfort

          I read it awhile back, I’ll dig for a source when I get home this evening.

  • johnBas5

    Wonder what the lifetime will be for nanoantennas if they ever come to market.

    First Optical Rectenna – Combined Rectifier and Antenna – Converts Light to DC Currenthttp://www.rh.gatech.edu/news/452781/first-optical-rectenna-combined-rectifier-and-antenna-converts-light-dc-current

    Nanoantenna Solar Cell Efficiency Can Blow Silicon Out Of The Water
    February 7th, 2013 by Nicholas Brown
    http://cleantechnica.com/2013/02/07/nanoantenna-solar-cell-efficiency-can-blow-silicon-out-of-the-water/

    Nanoantenna and Tunneling Diodes for Rectification of Mid-IR Light and Energy Generation
    http://www.umerc.umd.edu/projects/solar09

    • Ronald Brakels

      I would say nanoantenna lifespan would probably be less than silicon PV. This is because they depend on small structures for their performance and over time diffussion of atoms (I believe the technical term is smooshing) will degrade these structures, while diffusion of atoms in a silicon cell has less of an effect as it will still work if the atoms go walkabout.

      • Karl the brewer

        I really, really hope ‘smooshing’ is indeed a technical term! I shall use it liberally tomorrow 🙂

      • jeffhre

        As long as they go walkabout in relative densities, should be ok.

  • johnBas5

    Decades is already a long time.
    (Keeping in mind the average human live only spans less than a century.)

    There are even innovations to stop degradation:
    http://cleantechnica.com/2014/08/12/self-cooling-solar-cells-better-performance-reliability/

    Technology to Suppress the Degradation of Crystalline Silicon Photovoltaic Modules that Causes Output Decline
    – Coating glass substrate with a thin film of titanium oxide-based composite metal compound –
    http://www.aist.go.jp/aist_e/latest_research/2013/20130722/20130722.html

  • Marion Meads

    As for me, if the Solar Panels deliver their worth in less than 3 years, it would be well worth it. The 25-30 year warranty seemed to be unrealistic especially for Chinese manufactured panels, very few companies will survive that long.

    In China, especially, once they sold the panels for a profit, they then quickly disband the old company, and then have a new company in place, with the same factory, owned and operated by more or less the same people. The old company is now free of any liabilities as it doesn’t exist anymore. Then a new cycle of fleecing out continues. It can happen here in the US also.

    • Michael G

      Sounds like what I’ve heard about other Chinese cos. Sometimes they go “bankrupt” just before it is time to pay their employees.

      I suppose the solution would be to have the installer guarantee everything for 20-25 years. Like Solar City?

      • Jamset

        Do the workers not kidnap the boss and force him to pay?

      • WuestenBlitz

        20-30 years depending if you did a Lease/PPA or a purchase. There is a reason why Walmart and the Department of Defense chose SolarCity to do the majority of their solar projects.

    • Ronald Brakels

      A Chinese solar panel will typically have a 10 year product warranty which covers “defects in materials and workmanship”. And then a 25 year Limited Power Warranty which typically promises to replace, repair, or pay for a replacement if it is not producing electricity some amount above 80% of its rating in that time. So I suppose that if your panel fails after 10 years due to a defect in materials or workmanship then one would be out of warranty and out of luck.

      But the Chinese warranty isn’t really what you need to pay attention to. It is the warranty you get in your own country and whether or not it will still exist if your installer goes belly up. Or belly down. Or generally just goes away.

      Do not go for the warranty which says you have to post the panels back to China (at your own expense of course) to be tested if they fail.

      • Riely Rumfort

        Buy decent quality wafers in series/circuit, do armored wiring yourself for the output(minimal soldiering) and double-glass+seal them and there is no reason they can’t last 90+ years.

        • Ivor O’Connor

          Have any links to youtube videos?

          • Riely Rumfort

            I may look into if anyone has a youtube how to. I kind of have a plan in mind of how I’ll do it, with slotted glass and a locking glass peg. I’m sure there are simpler ways to the same effect but I’m thinking complete full proof solid encasing with armored cable with an interior neoprene(heat resistant) plug with the cable pressured into place by heat expanding the glass prior. I have both an outcome and firmly achievable method in mind, even a concept of inter-lockable glass panels for full 15x15ft arrays.  
            Found a nice abstract I thought I’d pass along as well.
            http://pubs.rsc.org/en/content/articlelanding/2015/ra/c5ra11224a
            Shows a pretty vast depreciation difference vs traditional.

    • Bob_Wallace

      Some companies keep responsibility for fulfilling the warranty. Other companies pay “insurance companies” to provide warranty coverage.

      If you are the fearsome type then you might check to see who is responsible for warranty claims.

      (If you’re just now extending your reach into China-bashing….)

      • Ivor O’Connor

        I usually like Marion’s input because it seems honest.

      • Marion Meads

        Now Bob Wallace is the typical CEO that will sell its soul over to China so that he can save money and have a bonus to buy a cup of StarBucks coffee, typically cheap CEO executive or wannabee.

        • Bob_Wallace

          Marion, I wouldn’t say that I harbor any dislike of you but I’m fairly sure you could create a bunch.

    • Steven F

      My understanding is that the panel warranty is provided by the manufacture of the panel. Not the installer. I can see the local installers going out of businessb. However I don’t see the major solar manufactures (even Chinese manufactures) going out of business very often.

      • Bob_Wallace

        A huge number of manufacturers have gone out of business over the last few years. One of the majors, can’t remember which, is in deep financial trouble right now and may not make it.

        • Marion Meads

          Of course your love for China is stronger than the truth about America and stronger than your dislike for the truths I’m telling about China.

          • Riely Rumfort

            What’s your deal tonight miss, seem fired up?
            Quit being so divisive, just don’t buy from China if that’s your choice. Especially not anything beyond the top 3 companies.
            If reliability were my only goal I’d personally buy European, Sweden/Gemany/Netherlands(sorry US) because their scale and testing seem most stringent.
            Since my life doesn’t, and the seldom dysfunctional panel can be replaced, I’d find the best sturdy looking well manufactured price-per-watt panel. I’d then buy a sample panel and test it for 9 months for efficiency losses as well as test the contacts for resistance and continuity between given wafer outputs.

          • Martams

            Don’t forget the Japanese such as The popular Mitsubishi panels!

          • Ivor O’Connor

            Marion, calm down, lets eat and have take our meds…

      • Marion Meads

        Many Chinese manufacturers have gone out of business, especially those US executives who have been duped into building solar PV manufacturing plants in China, they then promptly filed for bankruptcy, and their Chinese counterparts have taken over for micropennies on the dollar, with every IP legally transferred and all. And you know what, Bob Wallace gleefully supports such tactics, unbelievable! And he accuses me of China bashing! He never learns about patriotism.

        • Ronald Brakels

          Personally, I love everybody equally. Therefore my love for China is 4.375 times greater than my love for the United States due to the poulation differential. But if it makes you feel better, I love the United States 13.617 times more than my own country and 359.551 times more than Fiji.

          • jeffhre

            I’m tired of folks dumping on Fiji. It ain’t right I tell ya, it ain’t right at all!

        • JamesWimberley

          Every Chinese smartphone contains an ARM-designed microprocessor for which it pays ARM a small fee (pennies per core). ARM has nothing else to sell but IP. So far its business model has worked fine in China.

          I suspect you are among those American patriots who assume all technology is invented in the USA. In the case of solar PV, the first device was indeed made in Bell Labs. But the bulk of the later development was done in Japan.

          • Joseph Dubeau

            Are you sure that ARM microprocessor is made in China? No.
            What is at the heart of the complaint of TPP made by environments?

          • Steve Grinwis

            Many ARM microprocessors are made in China, yes.

            There are many different ARM cores made in many places, all by different companies. ARM doesn’t manufacture a single processor itself.

        • Joseph Dubeau

          You could go the China “consumer protection agency”
          and joined the other political prisoners.

          It’s a good thing we live in a Democracy.

          • Chuck Newton

            We Americans live in a republic, not a democracy. There is a big difference.

          • Joseph Dubeau

            Our Republic (United States of America) as you are referring to is a representatives democracy.
            We live in Democracy. It’s NOT the REPUBLIC of America.
            You are confused.

          • jeffhre

            Federal or local?

  • Ivor O’Connor

    It seems Enphase micro inverters have 20 year warranties and cost only $130 a piece. https://goo.gl/QejzVT Are there better deals?

    • Ronald Brakels

      Generally you can get a cheaper installation (in Australia at least) with a single central inverter. However, there are people who prefer the microinverter for various reasons and are willing to pay a little extra for them. One reason being their extremely long expected lifespan.

      (Sorry I can’t tell you any details about microinverter prices off hand.)

      • Ivor O’Connor

        I like the idea of micro inverters on each panel removing the risk of the string being only as good as the weakest panel. The ability to monitor each panel and the long 20 year warranties seem to make this micro inverter solution quite nice.

        • Ronald Brakels

          25 year warranties are available now. Can’t remember whose they are though.

          • phineasjw

            The SunPower 250W panels with integrated microinverters warranty both the panel and the microinverter for 25 years.

          • Riely Rumfort

            Beyond that there are a hand full of inverters which come with them now. I remember Sunpower’s all-in-one being one of the first too though.

          • Ivor O’Connor

            SunPower is wildly expensive and their sales reps love to ding every other manufacturer as being poorly made. They seem to love saying other manufacturers only warranty their panels for 10 or 12 years at which point if they go bad you’ll have to take them down and ship them to China yourself. Something about the 25 year warranties only being for the crystal itself and not the panel. Studies like the one here they purposely hide away. SunPower sales people have alienated me.

          • phineasjw

            They are more expensive than the Chinese panels and slightly to moderately more expensive than others like LG.

            I was quoted $4.70/W for the 327 panels, installed. Then shopped around some and found another installer who quoted $4.30/W for the 250AC panels with built-in microinverters. The best LG quote came in around $4/W, for their 300-BLK series.

        • Frank

          I like the idea of a battery backup, and an inverter being able to both grid tie, and produce AC power during an outage. That said, micro inverters certainly have some advantages.

          • Ivor O’Connor

            I’ve been looking at the solaredge solutions but they seem a bit sleazy too. What got my attention was how they would rate their dc to dc efficiency of 99% as if it were the total system. I’m rather big on honesty and when I see sleaze I figure there is more buried deeper.

        • WuestenBlitz

          Personally I don’t like micro inverters for the simple reason that if a single one goes out someone has to climb onto your roof and pull a single panel off to fix it. And statistically is won’t be the panel on the edge of your array. The risk of further damage and headache is not worth the extra production currently. And putting electronics on a roof in the Sonoran Desert is is a bad idea.

          • mike_dyke

            I agree. It also makes things difficult when you want to add in battery storage. The panels generate DC and the Inverter generates AC, so to put something like a powerwall in there, you have to connect it to the panel side (DC) of every inverter. With one main inverter it’s easy, but with lots of small ones it’s more difficult.

            However, If you’ve got easy access to the panels, then microinverters can have an advantage if ou’re worried about panel failure.

          • hank1946

            What about Solaredge system? From what I understand it is more efficient than micro inverters

          • mike_dyke

            I think you mean the power Optimizers. These work in slightly different way to the micro inverters.
            The micro inverters convert the the power from each panel into AC so that it can be fed directly into the users system effectively the DC to AC converter box that I talked to NRG4All about. The downside is that to use something like the Powerwall, you have to convert it back into DC.
            One of the functions of the central Inverter is a Maximum Power Point Tracker (MPPT) which looks at the DC output from each panel and takes into account shading etc to produce the maximum DC power.
            The Power Optimizers move that MPPT facility to the back of the panel (and also send information about that panel to the central inverter.) This reduces the work that the central inverter has to do and so it can be simpler.
            Again, from my point of view anything that adds to what’s on the roof is a problem BUT if they could be moved inside the roof along with the connections, then they could be OK.

          • jeffhre

            My understanding was that power optimizers allow string inverters to take off the full power of each panel, and not run the system at the power of the lowest (shaded) producing panel.

          • mike_dyke

            Yes, you’re correct and it’s the same as what I’m saying. The facility to work out the full power is called the MPPT (Maximum Power Point Tracker) When applied across a string of panels, it takes the power of the lowest (shaded) panel as the voltage. When applied to a single panel, it takes the power of the lowest “cell” taking into account shading.
            The benefit of putting the MPPT at the panel is that any unshaded panels output their full power rather than being reduced which increases the amount of power generated overall.

          • jeffhre

            Uh, no I said that. You said… 🙂

          • mike_dyke

            Uh, you said what I meant to say and thought I had but looking at the original post again, I hadn’t.

            My only excuse is it’s late at night here – Sorry.

          • jeffhre

            I have nothing but respect for that sir!

          • mike_dyke

            Thank you. FYI, last night we in the UK were putting the clocks back an hour due to end of summer time and so I was answering you at about midnight new time which meant it was about 01:00 old time – Way too late to be answering comments!

          • Ivor O’Connor

            Yes. Even if only one of your 50 panels fail in the 25 year warranty period then you have a 50% chance of having to do this repair. Maybe however one should wait for multiple micro inverters to go out before doing a repair?

            What I would really like to know is how frequently these micro inverters go out. I just talked with one sales person who claimed Enphase products go out all the time. Their sales pitch went along the lines of “When Enphase came out they had six year warranties and they haven’t changed their product. Instead for marketing reasons they claim they last longer and will eventually go out of business”. (They were pushing solaredge inverters.)

      • tibi stibi

        yes i have micro’s. they are more expensive but give a bit more energy and i wanted the most energy i could get even at a higher cost.

        they also give better information about each panel so i could detect if one is performing bad. and i’m flexible about the position and don’t have to worry to much when there is a bit of shade on one of my panels.

        the piece price in holland is less than 100 euro’s but you have to add cables and a the enphase (monitoring and regulator) i bought a set of 12 for € 1195 (landscape) and 1145 (portrait)

        • Ronald Brakels

          Good point about the extra power, since every panel (should) work optimally for the given amount of light falling on it. In a place like Holland where roof space is limited that can be an important consideration. Here in Australia though, just throwing on an extra panel to make up for losses is generally a valid option. And a cheaper option, for now.

          • tibi stibi

            yes i just want the max amount of power. i put solar panels on my roof but i use them also as roof above my porch and as fence around my rooftop.

    • Steven F

      In 2000 from what I have read the best warranties were for about 5 years. As engineers got better in there designs and failures pointed out weaknesses in the design, the reliability improved.

      Micro inverts are relatively new and have benefited from the central inverter experience. The warranty difference will probably not last as older designs are discontinued and new improved designs are released.

    • heinbloed

      Your link doesn’t work.

      The latest I saw for an Enphase 250 was € 170.-

      Enersys are much cheaper but not with that waranty.

    • Brooks Bridges

      Solar Edge makes an inverter splits the inverter functions into two components. 1) one part on each panel 2) another, simpler component for all panels in string. If one panel is shaded, only affects that panel. Local installer prefers them. They tried micros for a while but keep having to go out and replace them.

      • Ivor O’Connor

        It would be great to know how often the enphase micro inverters compared to the MPPT systems SolarEdge uses.

Back to Top ↑