2022 年 17 巻 2 号 p. 22-00051
Spacecraft use photovoltaics as power-generation systems. Although photovoltaics have advantages such as no requirement of fossil fuel or moving parts, a disadvantage is that generating power without sunlight is impossible. Spacecraft require new power-generation systems that do not depend on sunlight to make power generation possible in deep space where sunlight cannot reach. In this study, a thermoradiative (TR) system was investigated. The TR system generates power by thermal radiation from the TR cells to the surrounding environment. The possibility that the TR system would be most effective in spacecraft for which the surrounding temperature is 3 K was considered. Because the power generation of the TR system depends on the amount of radiation from the TR cells, the ideal state was simulated by assuming that the TR cell emits blackbody radiation to obtain the upper limit of the power generation. Furthermore, the effects of output voltage, cell bandgap, and TR cell temperature on the power generation were investigated numerically by using a HgCdTe photodiode, and the results were compared with those for blackbody radiation.
