Cleaning your modules is usually as simple as using a regular garden hose to spray them off. If additional soiling is present, a mild detergent may be used with a soft cloth or soft boat brush. Take great care and always follow the manufacturer’s cleaning instructions for your particular solar electric panel. If you need the instruction manual for your panel, ask your solar professional or search for the datasheet for your particular module model number.
Your solar professional can also be hired to wash your modules or recommend a service with whom they have worked. Never use a pressure washer, or abrasive or corrosive chemicals. Avoid spraying water directly on junction boxes or other electrical enclosures.