The exponential growth in solar PV installation is changing the landscape of management and operations and maintenance (O&M) of these plants.The average size of a utility-scale solar PV plant has grown approximately 12 times in the past five years, from 7 MWp in 2015 to about 90 MWp in 2020. Meanwhile, the size of a commercial rooftop installation has grown by approximately seven times in the same period. However, due to the cut-throat competitive market conditions, the payback period on these investments has increased from four to six years to 9-11 years. These numbers provide a clear picture of the mammoth task of managing these “investment grade” assets, and making sure that they remain operational for 15-20 years.
This arduous task of managing such widespread, large solar farms cannot be imagined without the adoption and deployment of automation technology. Solar PV O&M, with its known challenges of unavailability of skilled resources, remote sites, inadequate spares and tools, has always had opportunities to deploy automation technologies. But these challenges and the consequent technology deployment were always considered large players’ needs, and therefore seen as vanity by small players. With the disruptions caused by the Covid-19 pandemic, the case for automation has only improved.
Solar cleaning robots criss-crossing solar PV modules is the first image one gets when automation in solar PV O&M is discussed. Thanks to their inquisitiveness and the absence of any entry barrier, today developers have multiple options for robotic cleaning. Cleaning bots are available in two modes, dry and wet cleaning, and are mostly designed for specific plant layouts. Over the years, we have witnessed that robotic dry cleaning in humid areas is not effective, and semi-automatic or collaborative robots (CoBOTs) are preferred to completely autonomous robots. Humidity, along with dust, causes cementation, and sticky irritants such as pollen or bird droppings are not cleaned effectively by dry cleaning bots. The prohibitive cost of fully autonomous cleaning robots outweighs the generation yields they enable. With compulsions to employ locals at solar farms, and given their greater flexibility, CoBOTs, which can be operated in both wet and dry modes, are becoming popular. In addition, to reduce the risks that come with technology adoption and maintain the cleaning system, companies such as Inspire Clean Energy provide the “product as-a-service” option to customers.
Beyond simple remote monitoring
“Data is the new oil.” This statement does not exclude the solar PV industry. Third-party remote data collection and monitoring solutions provide large and flexible data analysis options to users. Their low hardware cost and the lack of an entry barrier for developing and delivering data visualisation platforms provides customers with a wide range of remote monitoring software to choose from. It is often said that if technology is implemented on inefficient operations, it magnifies the inefficiencies. While these low-cost, rudimentary software solutions can help users understand the inefficiencies, they cannot help users overcome those inefficiencies. Prudent data curation from various sources, cognitive data analysis, and user perspective-based data visualisation are in demand. Holistic login platforms for data curation, analysis, execution, reporting and document management solutions, such as EIRA.io, are being deployed by many. These asset management platforms, when deployed, help users collect data in less than three clicks and make informed decisions.
Drone and field management robots
With the average size of solar plants growing to 90 MWp, drones are being deployed by developers and engineering, procurement and construction companies. Beyond project management, drones are increasingly being used for thermal imaging. Calendarised schedules for flying drones over a plant in order to map module anomalies are part of the O&M scope now. Drones help in scheduling routine maintenance activities efficiently and optimally. The commercial viability of such deployments is still being studied, but with the falling prices of drone and software technology, they could become commercially viable in the coming years. Besides drones, solar PV field management robots have emerged in recent years. Products such as TrancoBoT have helped O&M companies reduce the time taken to clear vegetation, as well as the cost of vegetation cycles.
The final word
Most of the automation and technology solutions discussed above are being used or considered mainly to reduce or optimise the cost of operating solar PV plants. With cost being the main imperative driving the industry, one should not forget the quote, “Automation is cost cutting by tightening the corners, and not cutting them off.”