Once your solar panels are installed, you need to keep track of how much power you are producing and using on a daily basis. Invest in a quality monitoring system and look at the data as often as possible. If you notice your panels are not producing as much energy as usual, it might be time to clean them.
Heliocol customer Keith Gascoine in Tallebudgera, QLD reviews his happy experience using Heliocol solar pool heating.
Cleaning your solar panels does not need to be labor intensive. You want to avoid abrasive soaps at all costs, as they can deteriorate and even destroy your panels. So long as there is not caked up dust or bird droppings, frequent rinses with just hose water should be more than enough.