Power Consumption and Prototype Evaluation of IoT Devices for Environmental Monitoring Systems.

In this paper, we conduct experiments and evaluations of intermittent operation with the goal of reducing power consumption in IoT devices for environmental monitoring systems. This intermittent operation is realized by alternately transitioning the CPU between its normal operating states and a deep sleep mode with minimal power consumption. While increasing the sensing interval can reduce power consumption, it also increases the risk of data loss, thus presenting a tradeoff. This paper evaluates the reduction in power consumption by integrating three methods: (1) disconnecting power supply to modules not in use, (2) utilizing CPU’s low-power mode, and (3) minimizing power consumption through intermittent operation. From the experimental results, the ratio of static to dynamic power was calculated. The methods (1) and (2) are used to reduce static power consumption to the maximum extent, while for dynamic power, we demonstrate the relationship between the interval of intermittent operation, power consumption, and operating time. In this paper, we also show a result of long-term environmental monitoring experiment with our developed IoT devices.