As the solar segment expands, there is an increasing need to improve the efficiency of solar plants. This includes improving equipment performance, increasing longevity and minimising operational expenses. One key area where market technologies are evolving is operations and maintenance (O&M) of solar plants. With the rapidly increasing size and scale of solar projects, there is now a greater focus on optimising performance and reducing operational costs. As a result, efficient O&M has taken centre stage in the Indian solar industry. Maintenance strategies are being developed to ensure greater automation and remote monitoring.
Moreover, with the increasing size of solar plants and the expanding capacities of inverter blocks and transformers, it makes greater sense to move from a site-based model to a central model. Remote monitoring and automated solutions provide this opportunity.
Remote monitoring and automation
A solar power system consists of various components that need to be procured from a variety of manufacturers. A remote monitoring system can help tie these systems together by enabling communication with all kinds of components. The myriad components can be monitored simultaneously from a single dashboard. Since remote monitoring provides instant alerts, critical faults such as voltage fluctuations, mismatches or physical damage can be quickly addressed. This promptness can prevent further damage, thus saving on additional repair costs. A remote monitoring solution collects data from solar power systems over a long period of time. The data collected can be used to generate daily, monthly, or yearly reports for billing or keeping track of energy production and performance. Remote O&M can also help minimise losses in energy production by enhancing maintenance activities, and enabling better decision-making and utilisation of overall cost-saving techniques.
The automation of services in the solar segment has a strong business incentive. A primary benefit is the reduction in manpower costs. With falling tariffs for solar projects, O&M players are being pressured to run solar power plants efficiently at low costs while maintaining profitability. Automation can help with this, as O&M players can deploy technology to predict the future of components and assess plant performance in order to avoid penalties. This is crucial due to the stringent regulations set by the state authorities regarding scheduling, forecasting and deviation settlement, which penalise over- and under-generation of electricity by renewable energy plants.
Advanced technologies are being deployed to improve predictive maintenance. One such technology is the software platform, called EIRA, developed by Inspire Clean Energy, a Mumbai-based O&M service company. EIRA is based on the three-second and three-click concept, whereby a client is made aware of the status of solar plants in three clicks. EIRA logs into every project at 15-minute intervals to check the performance parameters of each inverter, energy meter and transformer. If a flaw is detected, it automatically generates a ticket and sends it to the nearest engineer. As soon as the problem is solved, a report is sent to the client. The platform also has a dashboard with smart tiles. The tiles stay green in normal conditions, and turn red if a corresponding inverter is down. It takes just three seconds for an investor to check this status, and three clicks for an operator to procure more information about a generated ticket.
Need for greater accuracy and calibration
The plant yield needs to be remotely monitored in order to identify faults without hindering plant operations. To this end, supervisory control and data acquisition (SCADA) systems are installed in most solar plants to ensure proper functioning. However, in the case of small distributed plants, web-based monitoring systems are used as they are more economical than large, expensive SCADA systems. These plants are usually monitored remotely rather than by a dedicated O&M team. The main difference between SCADA and web-based systems is that the former provides remote control functions, in addition to monitoring and data collection functionalities. In cases where SCADA and other control systems are already in place, regular and proper calibration of parameters must be undertaken to ensure the quality of data.
While drones, robots and smart sensors are decentralised, remote monitoring systems are set up at a centralised location. With various remote monitoring software solutions being developed, the accuracy of such tools is a crucial factor. The quality of data collected and the efficiency of real-time remote monitoring will determine the overall optimisation and cost savings. Small differences in the accuracy of environmental and operational data can lead to large margins of error on performance metrics. Hence, well-calibrated environmental sensors and granular, reliable monitoring are essential to ensure reliable data.
After the quality of data is ensured, the next element to consider is the automatic alarm, and when it should be triggered. To make the process of monitoring cost efficient, automatic alarms can be set up to indicate an area of concern to the operators without requiring them to sift through data manually. However, the accuracy of alarm triggers needs to be carefully improved to decrease the frequency of false alarms, thus improving preparedness for real faults.
Cloud-based IoT solutions and the future
Over the past few years, various technologies have emerged to improve predictive maintenance. These technologies have evolved from computer-based automated monitoring systems to drones, robots and wearables, and now to solutions based on artificial intelligence (AI) and internet of things (IoT).
One such emerging service is the cloud-based IoT and remote monitoring system. This service collects important parameters from a solar installation and makes them accessible remotely. Data loggers are used to transmit this data to cloud-based IoT platforms. The data on the platform can either be accessed in the raw form or be seen in aggregated forms, or as visual representations. With such a system in place, it becomes easier to monitor solar photovoltaic inverters, energy meters, weather stations, string monitoring boxes, protection devices, batteries, and other essential components. IoT-enabled wearables such as watches, headphones and armbands are also being used by many O&M players for remote monitoring of solar plants. While their use is currently limited to very small rooftop plants, there is significant scope for them in large utility-scale plants.
Free Spirits Green Labs has developed a SaaS product called TrackSo, which is an IoT-based energy management platform that tracks performance, spots or predicts failures, and provides proactive maintenance of assets. Coupled with smart data logging hardware, TrackSo performs remote monitoring and troubleshooting for all kinds of solar systems.
Other futuristic technologies are also emerging, such as AI-based digital twins. These AI applications can reduce the time and effort required for planning and analysis. Through them, a replica of an actual physical asset, known as a digital twin, is created to be used as a benchmark for identifying faults through data anomalies. However, the high cost associated with these technologies currently prevents them from being widely adopted.
Moving forward, the focus in the sphere of remote monitoring, automation and predictive maintenance will be on minimising costs while maximising efficiency. Of late, the use of robotics, drones and other automated tools for O&M is being surpassed by asset management tools and machine learning applications in terms of cost efficiency. However, the development of a more focused O&M strategy still requires significant investment. On the positive side, industry players are now more aware of the scope of automation and digitalisation. Good results from predictive maintenance have pushed an increasing number of players towards digitalised solutions in O&M, along with its promise of profitability.
With these advancements in the O&M segment, it is likely that the technological component of the segment will increase vis-à-vis the personnel component, and this will be reflected in costs. The setback experienced due to the Covid-19 pandemic has further fuelled the move towards greater digitalisation, especially in the field of renewable energy projects. As per industry estimates, by 2028, the share of personnel in total costs will come down to 17 per cent while that of digital equipment will comprise more than 50 per cent. At this point, the future of O&M seems to be rooted in AI-driven automated systems.
By Meghaa Gangahar