IoT-Based Greenhouse Monitoring and Control System Using NodeMCU ESP8266 and the EMQX Platform

Abstract

The advancement of Internet of Things (IoT) technology has enabled the automation of greenhouse management to improve agricultural productivity. However, conventional greenhouse systems in Indonesia still rely on manual monitoring, making it difficult to detect changes in environmental conditions promptly. This study develops an IoT-based greenhouse monitoring and automatic control system using a NodeMCU ESP8266 integrated with EMQX Cloud for secure and reliable MQTT communication. The prototype consists of irrigation, plant-monitoring, and climate-control zones. Environmental data from DHT22, YL-69, and BH1750 sensors are transmitted to a Node.js (Express.js) backend, stored in a Supabase PostgreSQL database, and displayed on a real-time Next.js dashboard using Socket.IO. Automatic control of irrigation and cooling systems is implemented through threshold and hysteresis logic. System evaluation included one week of laboratory testing and one month of field testing. The results show that the system successfully provides real-time environmental monitoring, stable automatic control, instant dashboard updates, and reliable device status monitoring, demonstrating its effectiveness as a smart greenhouse management solution.