While rainwater can help rinse off some loose dirt and dust from solar panels, it is not enough to keep them thoroughly clean. Similar to how a car's windshield gets streaked with grime even after a rainstorm, solar panels accumulate layers of dirt, pollen, and bird droppings that rainwater alone cannot remove. In fact, rain can sometimes leave behind mineral deposits and water spots, further reducing efficiency over time.

To ensure optimal performance, professional cleaning is often necessary, especially in areas with high levels of airborne debris. Cleaning services use purified water and specialized tools to prevent streaking or damage to the panels. Investing in periodic professional cleaning based on solar panel cleaning prices can help maintain peak efficiency and prolong the life of your solar energy system.