Development of ET-Based Irrigation System in Green Roofs Using Penman-Monteith Equation

Green roofs offer an opportunity for urban cities to increase their agricultural landscape without needing to consume ground area for soil. Nowadays, green roofs are still irrigated using the traditional method which poses a huge waste of water. Realizing this problem, the researchers explored the use of an Evapotranspiration (ET)-Based Irrigation System using the Penman-Monteith equation processed using a Raspberry Pi. With the use of multiple sensors: a DHT22 Temperature and Humidity sensor, Anemometer, and Flow Sensor, various parameters in the Penman-Monteith equation are satisfied in order to output each of their estimated reference evapotranspiration values. With the calculated reference evapotranspiration values, fuzzy logic is used in order to satisfy the amount of water being used for irrigation. Multiple sensors are first calibrated, tested, and observed in order to make certain that the acquired data by the system shall be as accurate and precise as possible. Having the calibrated sensor data, the Reference Evapotranspiration value is computed and is then converted to a volume amount using fuzzy logic. Finally, the water output is controlled using Solenoid Valves. The researchers had successfully developed the ET-Based Irrigation System.