Abstract
Operating a solar cell under thermal stress at temperatures >100 C and up to 500 C seems counterintuitive because conversion efficiency drops dramatically. Even so, there are cases in which solar cells are in high-illumination high-temperature conditions, for near-the-sun space missions and in various terrestrial hybrid systems involving solar-to-thermal energy conversion. This review analyzes the progress of solar cells tested in the laboratory under thermal stress. The fundamental physics governing the thermal sensitivity of solar cells and the main criteria determining the ability of semiconductor materials to survive high temperatures are recalled. Materials and architectures of a selection of the solar cells tested so far are examined. Deviation from the Shockley-Queisser limit at each temperature is used for a fair assessment of the performances. Our analysis reveals the strengths and weaknesses of the existing technologies and the gaps to be filled to develop new classes of solar cells capable of withstanding high temperatures.