DEWA Study Evaluates Performance and Safety of PV Cleaning Robots

## Performance Evaluation of PV Cleaning Robots A recent study conducted by a research team from the Dubai Electricity and Water Authority (DEWA) has evaluated the cleaning performance of several PV cleaning robots in a desert environment. The team assessed the performance of five autonomous dry-cleaning robots, which were deployed on both fixed-tilt PV systems and single-axis trackers. The robots were manufactured in China, India, and Greece by undisclosed companies. The study found that daily robotic cleaning reduced soiling rates from approximately 0.14-0.33% per day to below 0.02% per day. The evaluated robots achieved cleaning efficiencies of 69-99%, while electroluminescence and dark lock-in thermography testing found no robot-induced cell cracks or electrical defects over two years. ## Safety and Reliability Concerns However, the study also identified several safety and reliability concerns associated with the use of PV cleaning robots. These concerns include battery overheating, inadequate ingress protection, corrosion, frame misalignment, and UV degradation of polymer components. The study's authors noted that repeated cleaning caused minor wear to the anti-reflective coating, with greater abrasion observed for bristle-based cleaning than for cloth-based cleaning. ## Recommendations for Evaluating PV Cleaning Robots Based on the results of the study, the research team proposed a 12-point checklist for evaluating PV cleaning robots before deployment. The checklist includes recommendations such as using IEC 62133-certified batteries with thermal management, ensuring at least IP65/IP66 protection for electronic components, using UV- and corrosion-resistant materials, and conducting PV-specific abrasion testing. The study's findings highlight the importance of carefully evaluating the performance and safety of PV cleaning robots before deployment. By following the recommended checklist, stakeholders can ensure that their PV cleaning robots are safe, reliable, and effective in reducing soiling rates and maintaining the performance of their PV systems.