Design A Low-cost PV Performance Ratio Data Monitoring

Photovoltaic (PV) system’s performance ratio (PR) is used to measure the quality and performance of a PV system. The PR trend can be used to analyze whether a problem occurs in the system. With the advanced development of information and communication technology; nowadays, it is possible to build a real-time PR monitoring system. This paper explicates the design process of a low-cost PV plant’s data monitoring and its PR calculation using free open-access applications whilst following the guidelines on the International Standard IEC 61724. The in-plane solar irradiation and inverter’s daily AC yield energy data are retrieved using Node-red application and are stored in an MySQL database. Using MySQL query commands, the PR values are calculated from the measured data which then are displayed to a web-based application that is programmed using the Grafana application. In this paper, the considered PV system is a 10600 W PV rooftop with a 10kW grid-tied inverter.