The use of solar energy as a renewable energy source continues to grow, but many solar panel systems are still not equipped with real-time performance monitoring tools. This research aims to design and implement an Internet of Things (IoT)-based solar panel monitoring system using a NodeMCU microcontroller and the ThingSpeak platform. This system is capable of monitoring electrical parameters such as the voltage generated by solar panels, then periodically sending the data to the ThingSpeak server via a WiFi connection to be displayed in the form of graphs that can be accessed online. The INA219 sensor is used to measure voltage and current values directly, while the NodeMCU functions as a data processor and sends information to the cloud. Test results show that the system can work well and stably in displaying monitoring data in real-time, and allows users to monitor the condition of solar panels remotely easily. This system is considered effective, simple, and economical as a solar energy monitoring solution, especially for small to medium-scale needs. The results of the experiments conducted on the first day showed an average voltage of 15.52 V. On the second day, the average voltage was 15.05 V, and on the third day, it was 14.99 V, with productive hours from morning to evening.
Aryanto et al. (2025) studied this question.