Keeping solar panels clean for maximum efficiency
PV energy is the most capital-intensive renewable source of electricity. Reducing cost and increasing efficiency are key enablers of widespread uptake. Although PV systems with few moving parts are portrayed as virtually maintenance free, recent research demonstrated that cleaning of modules increased their efficiency 7–9 % regardless of age. Regular cleaning and maintenance could be particularly important in dry locations near the coast with a high content of particulate matter in the air — essentially the areas in which solar power generation is becoming increasingly important. A large consortium came together to develop a robotic cleaning and inspection system for ground-mounted, large-scale PVs with EU funding of the project PV-SERVITOR . With an estimated increase in electricity output significantly more than energy consumption by the robotic system, researchers targeted a sizeable net end-user benefit in the generation cost of grid-connected PV electricity. The Servitor robot is very flat to resist high winds. It is designed to move along the surface of the modules, sensing the level of soiling to adjust the pressure of its rotating brushes accordingly. Equipped with machine vision, it can detect the end of a row of modules or an obstacle including a dead bird or snow to changes its direction or its cleaning procedure. While further research is required to field test the robot under different climatic conditions and with various types of PV modules, research has already enabled the submission of five patent applications. Decreasing the cost of electricity production from solar energy will have major impact on widespread uptake of this most renewable form of energy.
