Solar Panel Maintenance in Summer

1 – Let the Rain Do Most of the Cleaning

Many homeowners assume solar panels need frequent washing, but that’s rarely the case in the UK. Rain naturally washes away much of the dust, pollen and dirt that accumulates on the surface of the panels. On roofs with a reasonable pitch, this is often enough to keep them clean for most of the year.

However, during long dry spells in summer, debris may begin to build up, particularly if your property is surrounded by trees or located near busy roads or agricultural land.

2 – Check for Dirt and Debris

Although a light layer of dust is unlikely to have a significant impact on performance, heavier build-ups can reduce the amount of sunlight reaching your panels. It’s worth carrying out a simple visual inspection from ground level every few weeks during summer, looking out for:

• Leaves
• Bird droppings
• Heavy pollen deposits
• Moss or algae around the edges
• Fallen branches after storms

If the panels appear particularly dirty, professional cleaning may be worthwhile.

3 – Avoid Climbing Onto Your Roof

If your panels need cleaning, safety should always come first. The Health and Safety Executive (HSE) advises against working at height unless it can be carried out safely with appropriate equipment.

For most homeowners, it’s best to avoid climbing onto the roof yourself. If cleaning is required, consider using a specialist solar panel cleaning company or speak to your installer for advice. In many cases, cleaning isn’t necessary unless there’s a noticeable build-up of debris affecting performance.

4 – Monitor Your Energy Generation

One of the easiest ways to check your system’s health is through its monitoring app or inverter display. Most modern solar installations allow homeowners to monitor electricity generation in real time. Keep an eye out for:

• Unexpected drops in generation
• Error messages
• Offline monitoring
• Significant differences compared with previous sunny days

Generation naturally varies depending on the weather, but a sudden or sustained reduction could indicate that your system needs inspecting.

5 – Keep Nearby Trees Under Control

Summer is when trees and shrubs experience their fastest growth. Overhanging branches can gradually begin casting shade across your panels, reducing the amount of electricity they generate.

The Energy Saving Trust recommends positioning solar panels in the least shaded area of your roof wherever possible, as shading can reduce system performance. If trees on your property are beginning to affect your panels, careful pruning may help restore generation. Always use a qualified tree surgeon where necessary.

6 – Check for Visible Damage

Solar panels are designed to withstand the British weather, including strong winds, heavy rain and hail. Even so, it’s sensible to carry out an occasional visual inspection from the ground, particularly after severe weather.

Look for:

• Cracked glass
• Loose panels
• Damaged mounting brackets
• Hanging cables
• Signs that wildlife may have nested beneath the panels

If you notice anything unusual, contact your installer rather than attempting repairs yourself.

7 – Don’t Forget Your Inverter

While the solar panels usually receive the most attention, the inverter is one of the hardest-working components of the system. Check occasionally that:

• There are no warning lights or fault codes.
• Ventilation around the inverter isn’t blocked.
• The unit remains clean and dry.

Most inverters display basic performance information, making it easy to spot if something isn’t operating correctly.

8 – Consider an Annual Professional Inspection

Although solar panels require very little maintenance, an occasional professional inspection provides extra peace of mind. An experienced installer can check:

• Electrical connections
• Mounting systems
• Inverter performance
• Cable condition
• Overall system efficiency

Routine servicing can help identify potential issues early and ensure your system continues operating safely and efficiently for years to come.