25 June 2026

When and how often should you have your solar panels cleaned?

The right timing gets the most out of the sunniest months: the maintenance calendar for your panels.

The most important moment is spring. From March to May the deposits of an entire pollen season sit on the panels, regularly topped up with a layer of Sahara dust after a southerly airflow. Cleaning then means going into the months in which the system produces the bulk of its yearly yield with clean glass.

A second logical moment is right after summer: an autumn visit removes the accumulated summer grime before the low autumn sun makes every stain weigh relatively heavier. Near trees, at the coast or with much bird nuisance, twice a year is the advice; in an open, clean environment one cleaning visit in spring is often enough. Two fixed visits usually fall under a cleaning subscription, which is cheaper per visit.

Don't count on rain doing the work: loose dust rinses off, but static grime, bird droppings, pollen and salt haze stay put: often as an edge along the frame where water lingers.

Signs you're too late: a visible haze or dirt edge on the panels, bird droppings still there after a few showers, or a yield lagging behind last year for no clear reason. If you're unsure whether it's soiling or the system, a yield check settles it; the rates are in the price index.