What is a solar panel warranty?
A solar panel has two warranties: a performance and equipment guarantee. A solar panel’s performance warranty will typically guarantee 90% production at 10 years and 80% at 25 years. An equipment warranty will typically guarantee 10-12 years without failing. SunPower offers the best warranties.
A solar panel’s product warranty insurance covers the integrity of the panel itself, and protects you against problems such as manufacturing defects, environmental issues, premature wear and tear etc. As with most warranties, a longer period is generally more advantageous to you, if you own your solar panel system. When evaluating a solar panel warranty and its manufacturer, the two most important factors on which you should focus are:
1. Product (or materials) warranty, and
2. The performance warranty
We’ll address both of these in this article as we break down our process for finding the best solar warranties offered by manufacturers.
What problems can solar panel warranty insurance prevent?
If you install a solar PV system for your home or business, by far your most likely scenario is that your panels will perform trouble-free for decades. But solar panel problems do occur from time to time, so if you happen to experience an issue with a solar panel after it’s been installed, it’s important for you to understand that the rest of your system will not be rendered inoperable—not by a long shot.
In all likelihood, depending on the nature of the panel failure, the rest of your system will just continue running with the failed panel left in place. But occasionally, panels fail in ways that impact the performance of neighboring panels. In either case, it’s the solar panel’s product warranty insurance that will cover you if you ever need to get a bad panel swapped out for a new one. A point to note, the cost of a single solar panel generally ranges from $150 to $300.
Evaluating and comparing the product warranty coverage of panel manufacturers can help assure you that your service and support needs will be covered if a solar panel problem ever occurs. Manufacturers’ product warranties are therefore an important complement to other considerations in assessing not only a panel manufacturer’s technical specifications, but also its business practices. In case a solar panel fails, the manufacturer will ship you a replacement panel and in some cases, even pay for shipping cost and labor cost to replace it.
How the Top Solar Panel Manufacturers Stack Up
The Exhibit 1 below summarizes the product warranty duration for the leading manufacturers who sell solar panels in the U.S. as of 2016. Most manufacturers offer a 10-year product warranty from the date of installation.
Exhibit 1: Solar Panel Product Warranty by Manufacturer
2. What is Solar Panel Performance Warranty?
The amount of electricity a solar panel produces declines slightly every year. That’s true of all solar panels, but to varying degrees. A common practice in the solar energy industry is to guarantee that the panels will not lose more than 10%-20% of their power output capacity over the first 25 years and is a crucial benefit of a good solar panel warranty. Said another way, panel manufacturers generally guarantee that their panels will produce electricity at 80%-90% of their power output rating at the end of 25 years.
Why does a solar panel warranty matter? How it impacts your PV system
A solar PV system represents a multi-decade investment. Your return on that investment is directly related to the amount of electricity your solar energy system generates year-after-year. The electricity generated by your solar panel system allows you to either buy little or no electricity from your utility. The less energy your solar system produces, the greater your dependence on the utility. It’s a zero-sum game. If the panels in your solar system degrade quickly over time, then you’ll derive less long-term value from your system than if your panels degraded more slowly.
Performance warranty coverage is yet another indicator of a panel manufacturer’s service and support policies in the event that you ever encounter a problem with your solar system. Whereas product warranty issues are fairly straightforward to demonstrate (either your panel is working or it’s not), proving that you’re experiencing a panel performance problem that should be covered by warranty can be far more subtle, the reasons for which are beyond the scope of this brief article. Suffice it to say that higher 25-year performance warranties (i.e., slower degradation) are viewed more favorably than lower performance warranties, but as a practical matter the performance warranty may be a better indicator of a panel’s intended degradation behavior than of its manufacturer’s support practices. If your solar panels degrades faster than what the warranty specifies, the manufacturer will either repair the solar panel or provide you with a replacement panel. Some manufacturers even pay to ship the solar panel to you and labor cost to replace the panel.
How the top solar panel manufacturers stack up
The Exhibit 2 below summarizes the 25-year performance warranties for the leading manufacturers who sell solar panels in the U.S. market. As you can see, most manufacturers warranty a 80% performance output after 25 years, with some manufacturers doing somewhat better than that.
Exhibit 2: Solar Panel Performance Warranty by Manufacturer
To learn more about solar panel products and performance warranties as well as other criteria to evaluate solar panels, see our research on how to select solar panels.