Real-Time Solar Irradiance Monitoring: An FPGA-Based Approach for Data Visualization

Measuring solar irradiance helps maximize efficiency in photovoltaic power plants. Devices for detecting solar irradiance, such as pyranometers, are difficult to calibrate and extremely expensive. Given these limitations, they are rarely used in photovoltaic power plants. This study explores the feasibility of monitoring solar radiation using an FPGA and low-cost, ambient light and power sensors. The monitoring of irradiance and illuminance was graphed and stored in a software application. Unlike traditional monitoring systems, this approach directly measured the electrical power generated by the cell as a proxy for solar irradiance. To validate the accuracy of the system, the measurements obtained were compared with a professional reference pyranometer (INIFAP). Linear regression analysis showed a linear correlation (R2) of 0.8115 between the system measurements and the high-cost reference pyranometer. In addition, accuracy was quantified using the Root Mean Square Error (RMSE) of 21.68 W/m2. The regression slope showed an average photovoltaic conversion efficiency of 15.44% during the test period, validating the system as an accurate, linear, and reliable tool for monitoring irradiance.