In the last several years, the United States has seen record growth in rooftop solar system installations among homeowners. In 2023, rooftop solar installations grew 27% with Texas, California, and Florida leading the way. As new solar technologies come to the market every day, it’s worth considering how long a solar system lasts and when it may need to be replaced.
How Long Will My Rooftop Solar Panels Last?
Solar panels provide significant renewable power and cut utility bill costs. While the average system’s power output diminishes slightly with time, most systems maintain at least 80% of their initial power output for at least 25 years.
A well-functioning system will last years longer than it takes to pay-off the initial investment. After that, homeowners pay nothing for solar energy to power their homes, so keeping your system for as long as possible is almost always the best option.
Nevertheless, some homeowners may consider replacing their existing system for a number of reasons – but what factors should you consider before doing so?
Why Would I Consider Replacing My Existing System?
Increasing power production: While keeping your existing system after it’s paid off allows you to generate free solar energy, you might want to increase the amount of solar power your system generates with new, higher efficiency panels occupying the same roof space. However, most solar systems sold over the last several decades decrease in power output by only about 1% per year. A better option to produce more power would be to add more panels to your existing system.
Another option to consider before replacing your system is to add solar energy storage, which provides resilience in the event of a power outage and allows you to avoid buying expensive power from your local utility after the sun sets.
Roof replacement: During a roof replacement, the solar panels and mounting system will need to be removed to complete the work. Some homeowners use this time to replace their solar panels as well. If you do not need a roof replacement for a few years, it may make sense to keep your existing system until you do.
What Factors Should I Consider When Deciding to Replace or Keep my Solar Energy System?
Cost of a new system: With an existing system that’s paid off, homeowners are paying nothing for their solar energy, often eliminating their utility bill. Purchasing new, higher efficiency panels may generate more, or even excess, power than old panels but now homeowners have the cost of paying off the new system to consider.
New utility programs: Check with your utility to see if they have any programs or policies in your area or state. For example, when purchasing a new system, you may encounter new utility policies like a reduction in the overall savings you receive when selling excess solar energy back to your local utility.
Can I Improve the Performance of my Existing System?
You can improve the performance of your existing system by completing regular maintenance and routinely cleaning the system itself. System owners can also consider updating certain parts of the system, like the inverters.
Are There Any Tax Incentives I Can Use When Replacing My Solar System?
The federal residential solar energy credit can be claimed on federal income taxes for a percentage of the cost of a solar system paid for by the taxpayer. The installation of the system must be complete during the tax year. For more information and to determine your eligibility, visit the Homeowner’s Guide to the Federal Tax Credit for Solar Photovoltaics.
Learn more about end-of-life management for solar photovoltaics.
What Do I Do with My Old System?
If you install a new system, work with your installer to determine a plan to haul away your old solar panels, ideally for reuse. If you chose to recycle your old system – you can visit the Solar Energy Industry Association’s website for a list of recyclers who accept solar panels.
DOE has invested in research and development projects that advance the reuse of solar panels. In 2016, DOE’s Solar Energy Technologies Office (SETO) awarded $700,000 to EnergyBin to create an online marketplace for overstock and hard-to-find components in the solar industry.
In 2022, SETO released the End-of-Life Management for Solar Photovoltaics Action Plan to maximize the environmental benefit of PV systems by improving end of life practices.
Most recently, SETO solicited proposals to improve the economic viability of recycling to prevent panels from ending up in landfills via its Materials, Operation, and Recycling of Photovoltaics (MORE PV) funding opportunity announcement. SETO supports hardware research to reduce the environmental impacts of end-of-life and reduce the costs of module recycling by more than half by 2030.
Check out the Homeowner’s Guide to the Federal Tax Credit for Solar Photovoltaics, Homeowner’s Guide to Going Solar, and learn more about SETO’s photovoltaics research.
