Will My Solar System Weaken Over Time?
The most frequently asked questions regarding solar energy systems involve longevity. It is hard to believe in 25-year warranties and 50-year life expectancies. Surely, if nothing else, the panels will degrade over that time, weakening the system’s output and gradually renewing my energy bills to their former heights. Right?
Not likely. The degradation of your solar panels is slow and depends on the type of panel. It is true that the panels will slowly weaken over time, but I’m talking about several years – a time frame the warranty will reflect. Conventional, crystalline silicon solar panels are the longest lasting, which is why they have the longest warranties. Most panels are warranted for sustained power output for 20 to 25 years. This means that up to 25 years should come and go before you notice any significant dip in panel production.
Remember that companies are not going to warranty something unless they are sure the product will perform as expected. Furthermore, because manufacturers are more likely to underestimate than overestimate expected performance, you will likely get even more life and quality from the panels than the warranty would indicate.
Note: Most warranties will designate a minimum percentage of output that a panel will maintain during the warranty period. This is typically around 80 percent over 25 years. That’s a healthy chunk of production left over.
Thin film solar panels are more prone to degradation. But, as sure as sugar is sweet, manufacturers are well aware of this and their warranties reflect it. Thin film panels are not likely to have a warranty lasting more than ten years at most. Although panels may last double that time. This is one of the reasons that conventional solar panels still dominate the market. Thin film manufacturers, though, are racing to ramp up efficiency and longevity of their products.
Solar panels in general are virtually maintenance-free. But this does not mean that they can be ignored. Debris, such as blowing leaves and shading may not cause degradation, but they will certainly affect power output. Panels do function in the shade, especially with a little Solar Magic, but not up to their peak potential. Regularly checking on your panels is an important and effective way to keep performance strong through the warranty period and beyond.
In conclusion, always read warranties thoroughly and consider them carefully when buying solar panels. If you’re looking to save money, you may be able to find refurbished solar panels at a lower cost but without much of a warranty. Panels, like anything exposed to extensive sunlight, will slowly weaken over time. But not considerable enough to really harm the panel’s output. Remember that solar panels are designed to sit in the sun; that is their job.
Posted on August 20th in Going Solar, Solar Information by Dan.
August 25th, 2008 at 10:50 am
[...] or belts to be torn. Nonetheless, they are not infallible. On the other hand, if your system stops working to its full potential, there is no need to look up emergency numbers in the phone book or to start spreading profanities [...]
August 26th, 2008 at 11:20 am
[...] I said, most high quality solar panels will have long-term warranties regarding panel function and degradation. This is due to the very makeup of the panels: no moving parts, protective tempered glass, [...]
October 26th, 2009 at 10:51 pm
I Purchased Photo Volteic Panels from Haebor Freight Tools and they only took 2 years to degrade to 25% of their original output. From 15 Watts per panel to 4 watts per panel. That is too much too fast yet they are the only company in America that will sell Solar Panels directly to the consumer without a 100% markup and some big sales pitch that they have the only good panels. Over priced, commision heavy contractors have locked up the market. Just like in the 1970s when solar hot water heating was overpriced because of Government rebates and utility programs. All HYPE yet there has never been a home owner system that produced enough to pay back their original investment, plus, pay for the replacement panels that “will be needed later” as ther old ones degrade, the inverters die and the wire isulation fails.
October 28th, 2009 at 11:08 am
About payback; most solar systems in the U.S. have been installed in only the last 5-10 years. There are many systems out there that, thanks to government incentives and rebates, have already paid for themselves. Quality panels come with at least a 20 year warranty…No salesman, regardless of pitch or angle, is going to warranty a product for 20 years that will degrade in two. Honestly, as a former construction worker I can say from experience that Harbor Freight sells low quality tools in general…apparently their solar panels are no different. Good solar panels and inverters cost a good deal of money, which is why we have government rebates in the first place. Furthermore, you can buy solar panels directly from suppliers, but it will cost you…although prices have been falling rapidly. Harbor Freight doesn’t claim to have the best panels for a reason…they don’t. As you unfortunately have learned. Inverters will need to be replaced, about every 10-15 years. They should be warranted for 10.
Solar power is an investment that WILL pay for itself over time, but it requires a quality product. The solar industry is extremely competitive right now as prices drop with demand. If you want to get the best deal on a panel that won’t degrade in two years, now is the time. You don’t need a contractor to buy the panels but, if you want the government incentives, you may need one to install them.
Thanks for writing in and good luck to you. Just remember that ALL products degrade over time. The wiring, drywall, paint, wood, anything in your home degrades over time and must be replaced. Solar panels are no different, although getting 25 or more years out of something that CREATES electricity is good in and of itself. If kept clean and maintained, there is no reason that it can’t last for 40 years or more. The first solar panel ever invented (in 1954) is still creating electricity today.