Looking after your solar panels: cleaning and checks

A solar system has no moving parts on the roof, which is why it lasts. That does not mean it looks after itself. Most lost output comes from a handful of small things that are easy to catch.

Keep an eye on the numbers

Your inverter or its app records how much the panels produce each day. You do not need to study it, but glance at it now and then. A sudden drop on a clear day, compared with similar days before, usually means something has changed: dirt, a shading tree branch, a tripped isolator or a fault. Gradual dips across a dry winter are often just dust.

Cleaning the panels

Highveld dust, pollen and bird droppings settle on panels, especially in the dry months when there is little rain to wash them. A light film costs some output; a bird dropping over part of a panel can cost more, because shading part of a panel reduces what the whole panel produces.

• Clean early in the morning or late in the afternoon, when the glass is cool. Cold water on hot glass can stress it.
• Use clean water and a soft brush or sponge on a pole. Skip detergents, abrasive pads and pressure washers, which can damage the coating and seals.
• Stay off the roof unless you have proper safety equipment. Panels are wired together and roofs are slippery when wet. If the panels cannot be reached safely from the ground, ask an installer.

Things to look at, not touch

From the ground or a safe spot, check for cracked glass, loose or sagging cables, and anything nesting under the panels. Indoors, make sure the inverter and batteries have the airflow around them that they were installed with. Storage boxes stacked against an inverter are a common cause of overheating. Write down any error code the inverter shows before resetting anything.

Leave these to an installer

Opening the inverter or combiner box, tightening electrical connections, replacing a damaged panel and checking the mounting after a storm all involve live DC wiring or work at height. Our maintenance and support service covers these, and a periodic check catches loose connections and corrosion before they cost you output.