The performance of a PV module will degrade due to fouling. Our primary aim is to supply the demands of the solar panel industry by providing them with a technology that reduces the use of water in solar panel cleaning. This way solar energy becomes a more efficient and cleaner energy source. The approach is to create an autonomous device, the Solar Farm Cleaning Robot, that is capable of cleaning solar panel farms in an eco-friendly, energy-efficient and cost-effective manner. The Solar Panel Cleaner Robot is a based on a proprietary cleaning roller that cleans surfaces easily in a wide zone with the assistance of a special microfiber textile. The operation does not require any water or energy supply hoses, and therefore, it is perfectly suitable for cleaning even at those places where electricity or water supply is not resolved. SINTEF has evaluated some parameters for the cleaning. A climate chamber for soiling and a test rig for the cleaning was build. PV panel glass plates was intentionally soiled in the climate chamber before different washing parameters were tested in the test rig. Light transmittance was measured before and after each cleaning.