Among the renewable energy sources, solar energy is the major source of electricity today, fulfilling almost 175+ GW of energy requirements globally. On a yearly basis, solar energy Production is increasing by 35% annually. A typical solar system consists of photovoltaic cells, inverter, wiring and storage batteries. With the passage of time, each component will deteriorate and will requires replacement. Failure to do so can and will effect the performance of the array. To get continuous sunlight and due to other factors, solar systems are normally installed at roof-tops and at remote locations in plain areas. It can be difficult to monitor the condition of solar systems and ensure all critical components, inverters, wiring, transformers and metering units, are working properly.
With time, the efficiency of solar plant decreases due to the deterioration of components. This deterioration can be caused from both internal and external factors. To make the efficiency and performance of solar system consistent, it is necessary to maintain the complete system and replace the damaged components as quickly as possible. it is very possible to see overall production of a solar system drop by nearly 20% if the components are not monitored and replaced in a timely fashion. To evaluate the performance of a solar system, there is a need for an accurate and real-time monitoring system to confirm its output. It must be capable of minimizing the plant shutdown time to minimize power breakdown issues. (Ejgar, Momin, & Ganu, 2017)
Sources of Deterioration
There are a lot of factors which affect the performance and efficiency of the solar system. There can be maintenance issues, uncontrollable and controllable factors which need to be minimized to get maximum efficiency of the solar system. Details of such factors are mentioned below.
Internal Factors
Internal factors are those which are mainly due to equipment itself. The durability of solar panels, fuses and inverters is the major contributor in maintaining the performance of the solar system. These factors are controllable and need to be monitored continuously to avoid any major plant shutdown or any overhauling requirement.
External Factors
Other than the internal factors, there are several external factors which are mainly dependent on the environmental conditions and working environment. Some of the external factors affecting the performance of the solar system are:
• Dust / Air
• Smoke
• Dew
• Cable Cuts
• UV Degradation
• Thermal Cycling
These external factors are mainly dependent on the location of installation. If a solar system has been installed nearby the fertilized lands or fields, there can be pests, insects and animals which can chew the cables. Solar systems installed near the commercial, industrial and populous areas, there can be smoke, dust and air pollution which can affect insolation and thusly the performance of the solar system. Similarly, heat and thermal cycles affect the life cycle of the components of solar system because of extreme ends of weather. Solar systems are designed to bear a certain range of temperature and environmental conditions. With the continuous change in environmental conditions, solar plates and other components become more prone to damage and reduced life. (What Maintenance is Required For Solar Electric Systems?, 2020)
Role of Monitoring
Proactive preventive maintenance and monitoring not only addressed problems with physical equipment, but ensure that there is no loss in electrical production which can cost a significant amount of money. Monitoring helps to check balance on the current profile, status of the circuit / each component and historical performance of the system. It helps to trace the decline in the performance of the system which acts as an early warning and action system to perform a maintenance work. Historical performance data of the solar system helps to determine the under-performing components of the system and they can be replaced in a timely fashion.
How Solar Monitoring Works
Solar Monitoring systems are normally linked to the inverters of solar system. There are monitoring software installed within the inverters to keep the information of power levels, equipment performance and production. This data is sent to cloud-based server and then it can be accessed using the applications or web-based portals. Similarly, real-time performance monitoring can be done using the on-site screen installation which directly connects the inverter with home screen through which data can be accessed and analyzed. There are a lot monitoring systems in market out of which
some rely on the internet connection and some are independent of the internet facilities.
Continuous monitoring of systems can help in identify the underperforming components and faults in the circuits. Along with the monitoring systems, there must be some routine inspections carried out to keep a check on the complete solar system. Following is the list of routine inspections:
• Visual Inspection of Solar Arrays and Wiring
• Operability check of all the connected wires with Solar System
• Function and visual check of all the switches & inverters
• Detailed inspection of the batteries based on OEM recommendations
• Electrical check of all hot-spots to check loose connections in a circuit