The data transmission system is important for the solar energy station monitoring system, where the system functions to send the output from the sensing element to the destination station. In practice, the generator location that scatters makes it difficult to monitor the performance data of the installed power plant. Monitoring is generally manually so that the parameters and monitoring data obtained are limited and not continuous. Therefore, the study uses an Internet of Things (IoT) system that combines a microcontroller with the sensors used for transmission process data by sensors to the database. The research purpose is to know the performance of IoT-based data transmission systems using a wireless network on solar energy stations and recommend a data transmission system that matches the solar energy station that can be displayed. The data transmission test results obtained the average packet value loss, delay, throughput, and jitter of 0.804%, 193,653 ms, 472,416 Bps, and 0.037 ms for plants with local servers and 0.348%, 68,818 ms, 860,875 Bps, and 0.009 ms for local server with an internet server. The results indicate that the applicability of the IoT system on the solar energy station can optimize the monitoring process of variable measurement by the devices in real-time.