If solar panels are not cleaned on a regular basis, they will eventually become dirty and less efficient. Over time, dirt and dust particles can block the sun's rays from reaching the panel's surface, making it difficult for energy to be produced from sunlight.A professional solar panel cleaning should occur at least once every six months in order to ensure that your solar system is running efficiently and optimally. Without regular cleanings, dirt and debris can accumulate over time which decreases the efficiency of the system by up to 25%. This decrease in efficiency quickly adds up over time as you end up losing money due to decreased production. Not only do soiled panels affect your wallet but they may also reduce the amount of electricity being produced or even cause permanent damage if left too long without servicing.