Spray the panels with a hose to remove loose dirt and debris. Over time, dust, pollen, bird droppings, tree sap, and other debris can cover panels, reducing their efficiency and power output. Cleaning them regularly helps ensure your system continues to generate as. Proper solar panel cleaning can increase energy output by 20% in a single session. Before starting any cleaning procedure. Discover everything you need to know about maintaining your solar panel: how often to clean it, how to wash it safely, and which tools to use to keep your system performing at its best.