For UK homeowners, selecting the right moment to clean solar panels can improve results. Experts generally recommend spring or early summer as ideal seasons. After winter storms and pollen season, panels often have accumulated dirt, so a thorough spring clean boosts summer output. A light follow-up clean in mid-summer can clear pollen or bird droppings. Many pros also suggest pre-autumn cleanings to remove any budding moss and avoid leaf-blockages in winter.
According to Checkatrade, the best time of day is early morning or late evening in spring/summer, ideally on an overcast daycheckatrade.com. Cleaning when panels are cool prevents water from evaporating too quickly and stops thermal shock. Avoid bright midday sun – wet, hot panels can crack if cold water is applied suddenly.
Image: Solar panels being cleaned with a soft brush on an overcast morning. Alt text: “Technician cleaning solar panels early in the morning under a cloudy sky.”
Winter generally isn’t the most efficient time to clean: low sun means a minor gain from a clean, though snow should be gently removed if it accumulates. In short, plan your cleans for moderate, dry weather in late spring and possibly again in summer. Many cleaning firms offer maintenance contracts or reminders to schedule in these optimal periods.
Image: A calendar page marked “Spring Cleaning” alongside a clear, clean rooftop solar array. Alt text:“Calendar with spring marked and clean solar panels in background.”
Call to Action: Plan your next cleaning for maximum benefit. Use our Find a Cleaner directory to book a professional in the right season and get the best out of your solar panels.
