Modern solar panels are built to last 30 years or more and require very little maintenance – which is exactly why they’ve become a popular investment for homeowners across the South East.
However, like any technology, they’re not completely immune to issues over time.
At SolarTherm UK, we regularly support homeowners across Essex, Kent and the surrounding South East with system checks, upgrades and troubleshooting. In this guide, we break down the most common solar panel problems, what causes them and how to prevent them – so you can protect your investment and maximise performance.
Reduced Energy Output
If your system isn’t generating as much electricity as expected, this is usually the first sign something isn’t quite right. Commonly reduced output is cased by dirt, dust or bird droppings blocking sunlight from getting through to the photovoltaic cells. Less commonly it will be due to shading changes, nearby trees, chimneys and buildings causing new shading issues that weren’t there when your panels were installed. Solar panels naturally degrade over time and even a thin layer of dirt can reduce efficiency, as it prevents sunlight reaching the cells effectively.
Regular cleaning every 12-18 months (or more frequently in high pollution or coastal areas) can prevent a build up of dirt, stopping your panels from losing efficiency. A visual check for shading, especially nearby trees that may need to be trimmed back can keep reductions in efficiency to a minimum by allowing you to trim back any problematic trees quickly.
The easiest way to keep your system in top operating condition is regular monitoring through your inverter or monitoring platform. Knowing what is normal for your system will help indicate when something is not working optimally.
Inverter Faults
Your inverter is the “engine” of your solar system – converting energy into usable electricity for your home. When it fails, your system may stop generating electricity altogether, so it’s important to check your inverter for faults regularly and get them resolved as quickly as possible. Error messages or warning lights, a blank display or a sudden drop to zero generation can all indicate an issue with your inverter. Inverters typically last 10-15 years, meaning they may need replacing during the lifespan of your panels.
Installing high quality equipment from the outset can improve the lifespan of your inverter, alongside periodic system health checks every 3-5 years. A visual check of your inverter, wiring and connections will alert you to any minor issues before they become expensive repairs. Remember when it comes to your electrical equipment, safety comes first so always seek professional advice and do not attempt to repair it yourself.
Physical Damage or Wear and Tear
Solar panels are designed to withstand UK weather conditions, but over time, environmental factors can take their toll. Microcracks from temperature changes, damage from storms and falling debris and gradual material degradation can cause small cracks that can reduce output without even being visible from the ground.
By choosing an MCS certified installer like SolarTherm UK, you can have peace of mind that the panels we install are MCS approved and of the highest UK quality and standards. Always carry out a visual inspection of your panels when it is safe to do so after extreme weather conditions.
Wiring and Electrical Issues
Thankfully, electrical faults are less common, however, when they do occur, they are usually more serious. Loose or corroded connections, damage from rodents or pests and poor installation can cause your solar PV system to fail or decrease generation. These issues don’t just reduce performance, in rare cases they can create safety and fire risks.
The easiest way to prevent electrical issues is to use a certified installer with solar experience when installing your panels. Book a professional maintenance or system check appointment if you notice any issues with the electrical system and never attempt a DIY repair.
Pests, Birds and Shading Problems
It’s not something many homeowners think about, but wildlife can impact solar performance. Common problems include birds nesting under panels, rodents chewing cables and vegetation creating shading and “hot spots”. Shading is one of the most common causes of avoidable performance loss in UK systems.
Preventing this is easier than you may think – installing bird mesh (preferably when you install your panels to avoid additional costs), keeping surrounding areas clear of trees and include your solar in your regular home maintenance routine.
Why Ongoing Maintenance Matters
Solar panels are often marketed as “fit and forget” – and while maintenance is minimal, it’s not zero. Regular checks help:
- Maintain optimal performance
- Extend system lifespan
- Identify small issues before they become costly
Most systems will naturally degrade by around 0.3-1% per year, making proactive maintenance even more important for long term savings.
Expert Insight from SolarTherm UK
With years of experience installing and maintaining solar systems across the South East, we’ve seen first hand that:
The majority of solar issues are preventable with good installation, quality components and simple ongoing care.
That’s why don’t just install systems – we support homeowners long after installation with:
- Performance checks
- Fault diagnosis
- Battery upgrades
- System optimisation
When Should You Get Your System Checked?
You should consider a professional inspection if:
- Your generation has noticeably dropped
- Your inverter shows error codes
- Your system is 5+ years old and hasn’t been checked
- You’ve experienced extreme weather
Final Thoughts
Solar panels remain one of the most reliable and cost effective ways to reduce energy bills and carbon emissions. While problems can occur, they are typically easy to identify, straightforward to fix and preventable with the right support.
Need Help With Your Solar System?
If you already have solar and something doesn’t seem right – or your installer is no longer available – SolarTherm UK is here to help.
We offer honest advice, system checks and expert support across Essex, Kent and the wider South East. Contact us today for a free, no obligation consultation. No hard sell – just clear, professional guidance you can trust.
Your home. Your energy. Your future.
FAQs
How often do solar panels need maintenance?
Solar panels require very little maintenance, but it’s recommended to have them checked every 1–2 years to ensure optimal performance and safety.
Why has my solar generation dropped?
A drop in performance is usually caused by dirt build-up, shading, inverter issues, or natural degradation over time. A professional inspection can identify the exact cause.
How long do solar panels and inverters last?
Solar panels typically last 25+ years, while inverters usually need replacing after 10–15 years depending on usage and quality.
Can I clean my solar panels myself?
In some cases, yes — but it’s safer and more effective to use a professional, especially for roof-mounted systems, to avoid damage or injury.
What should I do if my installer is no longer available?
You can contact a trusted, local installer like SolarTherm UK for system checks, repairs, or upgrades — even if they didn’t install your original system.
