問74
頻出度★☆☆
IoT デバイスへの電力供給でも用いられ，周りの環境から光や熱 (温度差) などの微小なエネルギーを集めて，電力に変換する技術はどれか。
令和2年度 ITパスポート試験 問74
This question's explanation and your answers so far.
解説
問 74
Incorrectア
PLC (Power Line Communication) is a technology that uses existing power lines as the transmission path to carry out data communication. It is not a technology that collects power from the environment to generate electricity; it is only a communication mechanism, so it is wrong.
Incorrectイ
PoE (Power over Ethernet) is a technology that supplies power at the same time as communication by using a LAN cable (Ethernet wiring). It sends power through the cable and does not collect and convert tiny amounts of energy from the environment, so it is wrong.
- ウ
正解 The correct answer is ウ, energy harvesting. Energy harvesting (environmental power generation) is a technology that collects tiny amounts of energy present in the surrounding environment, such as light, heat (temperature differences), vibration, and radio waves, and converts it into electricity. The amount of power generated is small, but because it removes the need for battery replacement or wiring, it is used as a power-supply method for IoT devices and sensors that are deployed in large numbers outdoors or in places that are hard to reach. This matches exactly the stem’s description of collecting tiny amounts of energy such as light or heat (temperature differences) from the surrounding environment and converting it into electricity.
Incorrectエ
A smart grid (next-generation power transmission network) is a power-grid mechanism that uses IT to optimally control the supply and demand of electricity. It aims to balance and improve the efficiency of power across the whole grid and is not a technology that generates electricity from tiny amounts of environmental energy, so it is wrong.
ここがポイント
- Energy harvesting (environmental power generation) = a technology that recovers tiny amounts of environmental energy such as light, heat, and vibration and converts it into electricity. It needs no battery replacement and suits powering IoT devices and sensors.
- Distinguishing confusable abbreviations: PLC = power line communication, PoE = powering over a LAN cable, smart grid = next-generation power transmission network. None of them is about recovering tiny amounts of environmental energy.
用語