Sinfonia Technology Co Ltd announced Nov 26, 2013, that it has developed a robot that autonomously moves around and cleans solar panels at mega-solar (large-scale solar) power plants.
Equipped with a battery, it cleans solar panels with a rotary brush and wiper while automatically moving on them and sprinkling washing water stored in its tank.
The new robot has a camera and various sensors and autonomously moves around, eliminating the need to install rails. It can clean an area of 100m2 per hour.
To clean tilted solar panels on a mounting system, the robot can move on a plane tilted at 5-30°. Even when the surfaces of the panels are wet due to rain, etc, it can move on a plane tilted at 20°. When there is a gap between panels, it can go over a gap of 50mm or less and deal with a height difference of 30mm or less.
Moreover, the robot is capable of wireless data transmission, enabling to check its status with a tablet computer (such as remaining battery charge and washing water). When the battery charge is running out, it stops on the lower part of the panel being cleaned. After the battery is replaced, it restarts cleaning based on recorded location information. The battery can be quickly replaced so that the cleaning task is not interrupted much.
Furthermore, the robot is equipped with LEDs having wavelengths in the infrared range and can clean panels even during nighttime hours.
At mega-solar plants, dust, sand and bird droppings are often attached to the surfaces of solar panels, lowering power generation capacity. According to Sinfonia Technology, which is based in Minato Ward, Tokyo, they can lower power generation efficiency by up to about 5%, which is equivalent to an annual loss of about ¥1 million (approx US$9,845) per 1MW output power. If those panels are cleaned by using manpower, its cost might affect the profitabilities of the plants.
Correction Notice: Due to a reporting error, we inaccurately stated that the robot can go over a gap of 50cm or less and deal with a height difference of 30cm or less. It can actually go over a gap of "50mm" or less and deal with a height difference of "30mm" or less.