Application of Electric Double Layer Capacitor and Water Level Sensor to Rice Field Monitoring System

In this study, we report the development results of an electric double layer capacitor (EDLC) as a power supply system and a novel water level sensor to monitor water level of a rice field. We also demonstrate a wireless sensor network (WSN) system to monitor water level of the rice field using the ED LC and the water level sensor. We fabricated the EDLC using material with low environmental load and a charcoal (charcoal EDLC). We realized a stable power supply system for the WSN system by combining the charcoal EDLC with photovoltaic modules. The WSN system, which was experimentally installed in the rice field, was successfully operated by the charcoal EDLC power supply system. Moreover, we propose the water level sensor, which is not affected by contaminants caused by water intake in rice field. The water level sensor carried out indoor demonstration experiment using a water tank simulating water intake in rice field. As a result, we confirmed its performance and availability for use in the management of rice field water intake.