Photovoltaic (PV) energy is currently the third-largest source of renewable energy (after hydropower and wind energy) in the world. Due to lower costs and flexibility in deployment location, it is one of the most rapidly growing sources of renewable energy. However, one of the major barriers to the large-scale deployment of solar power is the extensive manual labor involved in the installation and maintenance process of PV systems. Installing PV panels at large farms can take thousands of man-hours. After installation, the panels have to be regularly inspected and cleaned to avoid soiling (accumulation of dust, vegetation, and bird droppings), which can reduce PV electricity generation. These tasks can significantly benefit from automation in terms of speed of operation, cost, and reliability. Robots can work both day and night, without safety risks, and cut down operation costs. As a result, robots that install, inspect, and maintain PV panels have been in discussion in tech communities since as early as 2012, and there have been several developments since.
We can categorize PV automation into three segments: installation, inspection, and maintenance. Below is a list of some active players in each of these categories:
|Brittmore Group||Robotic installation equipment for utility-scale solar||Installation||Wait and See|
|Heliostouch||A Kickstarter project to use robotic arms to install PV panels||Installation||N/A|
|Heliolytics||Aircraft-based inspection of photovoltaic systems||Inspection||Positive|
|Birds.ai||Drone-based visual analytics and AI-enabled software for asset inspection||Inspection||Wait and See|
|Aerospec Technologies||Drone-based visual data analytics for solar O&M||Inspection||Wait and See|
|AVA Asia||Drone-supported thermal imaging and defect detection for solar installation maintenance||Inspection||Wait and See|
|Raptor Maps||Drone inspection software for solar analytics and maintenance||Inspection||Engage|
|Arborea Intellbird||Drones for wind turbine and solar inspections||Inspection||Monitor|
|Cleandrone||Drone-based inspection and cleaning services for PV plants||Inspection + Maintenance||Monitor|
|Ecoppia||Water-free PV panel cleaning robots||Maintenance||Positive|
|Solarbrush||Automated cleaning tool for ground-mounted solar projects||Maintenance||Wait and See|
|FlipRobotics||Portable water-free cleaning robot for utility-scale solar||Maintenance||Monitor|
|Skilancer Solar||Self-powered cleaning robot for utility-scale photovoltaics||Maintenance||Monitor|
|SolarCleano||Dry and wet cleaning robots for solar modules||Maintenance||Monitor|
|Ecovacs Robotics||Water-free solar panel cleaning robots||Maintenance||Caution|
Although the above list is not exhaustive, it is clear that activities in inspection and maintenance are ahead of installation due to the complexities involved in automating the balance of system (BOS) of PV panels. There are different sizes and types of panels installed on different surfaces (e.g., rooftops and ground mount). Installing such a diverse set of panels requires highly versatile product-agnostic robots. Only Brittmore Group seems to have developed a working solution so far. That said, even Brittmore's solution is not fully automated and requires human intervention. In addition, due to the deployment costs, the company isn't interested in projects smaller than 2 MW (here’s a working demo of the installation process). However, there have been developments in the automation of system design from companies like Terabase Energy and Aurora Solar. These companies create 3D models of design sites using satellite and lidar images, which makes subsequent installation easier and reduces soft costs (read a related case study).
Inspection of defects in photovoltaic panels has seen an influx of startups that leverage the recent advancements in UAVs like drones. Most companies use off-the-shelf drones and computer vision, thermal imaging, and machine learning algorithms to detect panel and cable defects. After a defect is detected, the area that requires cleaning or maintenance is analyzed and shared with operators or cleaning robots. See the automated inspection systems Tech Page and the insight "Driving factors of the next generation of automated inspection systems" for more details.
In addition to incumbent methods like drones, airplanes, and robotic inspection, satellite imaging is also emerging as a potential method of inspection of solar panels. Stanford engineers have already developed an algorithm that can detect and estimate the area of rooftop solar panels. As the technology matures and spatial and spectral resolution improves, companies like Planet, Orbital Insight, and Satelytics could offer inspection of solar panels on a very large scale. See the report "The Next Generation of Satellite Imaging" for more information.
Similarly, the maintenance of PV panels is a crowded market. Traditionally, companies used a cleaning arm that glided across the surface of PV panels and used liquid cleaners (or just water) to clean the surface of the panels. The industry then slowly moved toward dry cleaning with rotating microfiber brush heads due to the complexities associated with wet cleaning, such as logistics, cost, and sustainability (wastage of clean water). Another crucial aspect to consider with maintenance robots is their weight and the potential damage, such as microcracks on solar cells. SolarCleano claims that its 80 kg robot has passed a series of electroluminescent tests to ensure that it doesn't cause any damage to PV modules.
Furthermore, some companies, such as Solarbrush, have migrated from such mounted cleaners to drones, which has enabled them to clean panel surfaces with theoretically less human intervention. However, drones come with their own problems, such as limited flight time and smaller payload capacity, which limits the size of the brush, thereby slowing the cleaning process.
In a nutshell, while some tasks in PV operations have been automated, developing a fully automated PV solution will still take several years. Clients looking to fully automate PV operations should start adopting inspection and maintenance automation solutions while monitoring developments in installation solutions. Innovations in materials science (low-weight materials like carbon fibers and self-cleaning or anti-soiling surface coatings), better design of robotic grippers, and batteries (for longer drone flights) will accelerate the developments.