Theoretical and Experimental Study of Thermoradiative Cells for Space Power Generation

Reliable power production is always a core element when engineers design a space mission. Typically, III-V solar arrays are used due to their high efficiency, radiation tolerance, and overall reliability. One downside of photovoltaics involves the need for incident light from the Sun. There are many places in the solar system and beyond that do not have access to sustained, high concentration solar radiation. As missions fly farther from the Sun, the available light power decreases with the inverse square of the distance. This means that missions past Jupiter are only receiving one tenth the solar power compared to Earth. In these scenarios, power can be produced by converting the heat from a radioisotope using thermoelectric devices. This study will demonstrate experimentally and theoretically that heat can be converted using another device named a thermoradiative cell (TRC). This cell is heated above the temperature of the ambient which causes a net flow of photons out of the cell. To sustain this, electrons from the circuit must be pulled in which causes a current to flow. This project explored this mechanism by using detailed balance calculations to predict an upper limit power and current generation as well as some loss mechanisms. An experiment was also conducted to demonstrate this effect under space-like conditions and a measure power was produced.