Solar panels are a long-term investment in your home, your wallet, and the planet. With the right care, they can provide clean energy for 25 years or more. But like any technology, a solar system goes through a lifecycle and it’s natural to wonder what checks are needed as your system ages, or whether those phone calls you’re getting about your “outdated panels” are genuine.
At Greener Homes, we’re here to help you make sense of it all.
The First 5 Years: Smooth Sailing
- Performance: Most modern solar systems should operate with little to no noticeable degradation in the first five years. Panels are designed to be durable, with only very slight drops in efficiency over time (around 0.3–0.8% per year depending on quality).
- Checks:
- Monitor your generation meter and energy bills – you should see savings and generation consistent with your installer’s projections.
- Keep panels clean by allowing rainfall to do its job; only consider professional cleaning if you live in a particularly dusty area or have persistent shading (like bird droppings).
- Inverter warranties often last 5-10 years, so this is the point to double-check your paperwork and understand what cover you have.
- This is also a good stage to review your electricity tariff. If you’re exporting power back to the grid, you’ll want to check whether you’re on the best deal. See our guide: Are You Getting the Best Rate for the Solar Power You Export? – FIT or SEG?
At 10 Years: The Inverter Checkpoint
- Inverter Lifespan: Inverters – the part of your system that converts solar energy into usable electricity – usually last 10–15 years. Around the 10-year mark, it’s sensible to:
- Review whether your inverter is still working efficiently.
- Plan ahead for replacement, which can cost £800–£1,500 depending on type.
- Panel Health: Panels themselves should still be performing well, though you might notice a gradual reduction in peak output compared to year one.
- Checks:
- Have a qualified professional carry out a system health check, ensuring cabling, isolators, and connections are in good order.
- Check your warranty – most panels have 20–25 year performance warranties.
Beyond 15-20 Years: Planning for the Future
- Panels: By year 20, most panels are still generating, though at a slightly reduced capacity (typically 80–85% of original output).
- Upgrades: This can be a good time to consider pairing your panels with battery storage, if you haven’t already, to maximise the benefit from your system.
- Checks:
- Inspect for physical wear such as frame corrosion, loose cabling, or cracked glass (though rare with quality installations).
- Confirm that your inverter has been replaced or serviced as needed.
- Review whether newer technologies might add value (e.g. smart monitoring systems).
Scams and Misleading Sales Tactics
Unfortunately, as solar has become more common, so have unscrupulous sales calls. Common warning signs include:
- Cold calls or letters claiming your system is unsafe or “out of warranty.” Genuine contractors rarely contact you out of the blue.
- High-pressure sales tactics encouraging you to buy unnecessary “upgrades” or “extended warranties.”
- Fake maintenance packages that offer little more than a visual inspection you could book with a trusted local installer at a fraction of the cost.
Tip: Always check the credentials of anyone offering solar servicing. Look for TrustMark or MCS accreditation, and if in doubt, hang up and do your own research. You can also read our full guide on spotting solar retrofit scams in the UK to learn more.
Your Checklist for a Healthy Solar System
- Monitor your generation meter and energy bills regularly.
- Keep an eye on your inverter performance – plan for replacement around year 10–15.
- Arrange periodic professional checks (every 5 years is sensible).
- Stay alert to scams – never feel pressured into buying over the phone or at your door.
Worried About Your Solar System?
If you’ve had your solar panels for a few years and are unsure what maintenance is due – or if you’ve been contacted by someone claiming your system is “too old” – give the team at Greener Homes a call.
We’ll give you honest, independent advice so you can enjoy the benefits of solar energy with confidence, and avoid being caught out by unnecessary costs.