Real-time IoT monitoring system for green roof microclimate in tropical region

IPB University, Civil and Environmental Engineering, 16680 Jawa Barat, Indonesia

^* Corresponding author: yudi@apps.ipb.ac.id

Abstract

Green roofs offer a sustainable solution for urban areas by reducing the heat island effect, improving thermal comfort, increasing green open spaces, and supporting environmental sustainability and urban resilience in the context of climate change mitigation. However, automatic and systematic monitoring of microclimate parameters such as temperature and humidity on green roofs is still rare. This study aims to design and implement a monitoring device based on the ESP32 microcontroller that can measure, store, and transmit data periodically and in real time. The system uses DS18b20 sensors for soil temperature and a DHT22 sensor for air temperature and humidity. Data is collected every 15 minutes, displayed on an I2C LCD, saved to a microSD card, sent to Google Sheets, and visualized through the Blynk IoT smartphone app. Calibration using water media and reference instruments showed high accuracy with R² values of 0.9925– 0.9966 for DS18b20 and 0.9910 for DHT22 temperature. Results indicate 100% recording success for DS18B20 and 98.81% for DHT22. The non- vegetated box (DS4) recorded higher maximum temperatures, indicating vegetation’s role in stabilizing soil temperature. Built for Rp. 350,000, this system offers a reliable, cost-effective solution for monitoring of temperature and humidity in green roof.