Development of a Low-Cost Solar Data Logger Using a PV Panel

Abstract

With the increased popularity and lower cost of PV panels, Novia University of Applied Sciences is planning to install a PV system on the roof of the university building. This thesis aimed to create a low-cost solar data logger for the project's feasibility study.

The device created uses an ESP32 as a controller and logs the data through MQTT protocol. The sensor is based on a 5 W PV panel and uses an INA219 combined with a MOSFET-based electronic load to obtain the partial I-V characteristics in under five seconds with a resolution of 64 I-V data points. This data allows quantifying the ideality of the environmental conditions for PV power generation. The logger is battery-powered and can use PV power to recharge the battery.

The manufacturing of a prototype was partially done. The short-term operation in laboratory conditions was validated. Long-term outdoors testing of a complete model and validating the measured magnitude are pending. The manufacturing cost of a prototype is estimated to be about 75 €.

The concept of this device is an interesting alternative to traditional pyranometers, which measure solar irradiance and can prove to be useful to assess potential areas of PV power harvesting or monitor already existing systems.