IPA IP 2020 Question 74
A question IPA Japan published in 令和2年度 10月 ITパスポート試験 公開問題 問74, translated into English. ITPEC is based on the same exams.
Which of the following is a technology that is also used for supplying power to IoT devices, and that collects tiny amounts of energy such as light and heat (temperature differences) from the surrounding environment and converts it into electric power?
Explanation
Energy harvesting — gathering tiny amounts of energy from the surroundings, such as light, heat, vibration or radio waves, and converting it into electric power.
Small solar cells generate power from indoor light, thermoelectric elements from a temperature difference, and piezoelectric elements from vibration. The power is small, but enough for IoT sensors that need very little, so devices can run where wiring is impractical and batteries would otherwise have to be replaced.
Answer (c)
Why not others:
- •(a) PLC — Power Line Communication sends data signals over power lines; it is a transmission path, not a source of power
- •(b) PoE — Power over Ethernet supplies power through a LAN cable from network equipment; the power comes from the network, not from the environment
- •(d) Smart grid — a power grid that uses IT to monitor and control electricity supply and demand; it manages the grid rather than collecting energy at a device
Key rule: Energy harvesting = power from the environment; PoE = power over a LAN cable; PLC = data over power lines.
Networks · AI-written, may contain errors
This question comes from the past questions IPA Japan publishes, translated into English by ITPEC Practice. ITPEC Practice is an independent study tool and is not affiliated with IPA or ITPEC. See the original paper (PDF) or Report an issue.