When investing in solar panels, it’s natural to ask: how long will they really last? After all, a solar system is a long-term commitment—and you want to be confident in your return on investment.
At SolarTherm UK, we bring over 15 years of hands-on experience in the solar industry. We’ve worked with virtually every type of solar panel available on the UK market, from early-generation systems to the latest high-efficiency models. That means we know exactly how different panels perform over time—both in theory and in the real world.
In this guide, we’ll break down:
- How long solar panels typically last
- What affects their efficiency and output over time
- What you should know about warranties and performance guarantees
- Tips to maximise the lifespan of your system
Whether you’re considering a new installation or just want to understand your existing setup better, this article has everything you need to know about the lifespan of solar panels in the UK.
What’s the Average Lifespan of a Solar Panel?
Studies show that solar panels last for around 30 years. The average solar panel loses efficiency by around 0.4-0.5% every year. Typically most solar panels come with a 25 year manufacturer warranty, which guarantees power output at certain levels across the lifespan. At SolarTherm UK we install Bovill.tech solar panels, which come with a 99-year warranty – so your investment is protected for longer.
What Happens After 25 Years?
Your solar panels don’t just stop working, they will continue to produce electricity, just with a lower output. Typically, solar panels will perform at their best for 25 years, continue to produce satisfactorily until they are 30 years old, and potentially produce electricity for 40-50 years. At the end of their lifespan, solar panels can be recycled and the glass, silicon and aluminium can be redistributed to make new solar panels.
Understanding Solar Panel Degradation?
Over time, solar panels start dropping in their efficiency. At SolarTherm UK, when calculating your annual output and savings we take account of degradation. Extreme temperatures take their toll on your solar panels and long-term exposure to UV rays are likely to increase degradation rates. Luckily, in the UK we don’t experience many extreme weather events and solar panels in the UK are expected to keep 96% of their generation capacity even after 20 years.
What Determines How Long Solar Panels Last?
Solar panels are affected by many different factors, but overall, the quality of the panel, the installer and yourself make the biggest difference to how long your solar panels last.
- The quality of the solar panels – While some solar panels have a cheaper upfront cost, you are likely to pay more in the long run. Cheaper panels use lower quality materials and have a lower efficiency rating, meaning you don’t generate as much power. At SolarTherm UK we use Bovill.tech solar panels that come with a 99 year warranty.
- The quality of the installation – To maximise optimisation of your solar panels, they need to be fitted correctly. Choosing a MCS and NICEIC qualified installer like SolarTherm UK ensures your system is installed to the highest level and everything is set for maximum efficiency.
- How well you maintain your system – While solar panels require very little maintenance once installed, it is important to monitor the generation of your solar system to ensure any issues are noticed quickly, leaving your panels running while not optimised can cause them to degrade quicker. Keeping your panels clean and debris free is also helpful, while solar panels are installed to minimise the amount of dirt they collect (installed at an angle so it slides off) occasionally they may require cleaning. Also checking for new areas of shading will keep your panels working to their full capacity for longer.
Protecting Your Investment for the Long Term
Solar energy is one of the most cost-effective, reliable, and sustainable energy solutions available today. And with the right combination of quality panels, professional installation, and simple maintenance, your system can generate clean energy for 30 years or more.
Ready to Start Your Solar Journey?
Join thousands of UK homeowners already saving with solar. Our expert team at SolarTherm UK is here to help you every step of the way – no hard-sell, just honest, expert advice – we let the figures speak for themselves.
