Photoelectrochemical solar cells: Temperature control by cell design and its effects on the performance of cadmium chalcogenide-polysulphide systems

The results of experiments probing the influence of various design parameters of photoelectrochemical cells on light-induced heating of such cells are presented. Both simulated (indoor) and outdoor experiments were performed. The use of a proper cell design allows a large degree of control over the operating temperature range of the cell. The temperature dependence of the photovoltaic performance of cells using CdSe and Cd(Se, Te) thin film polycrystalline photoelectrodes in aqueous polysulphide solution was found to depend on the individual photoelectrode. A general trend showing an optimal temperature range above room temperature can be discerned. Systems with higher conversion efficiencies tend to have a higher optimal temperature range than those with poorer efficiencies. This is attributed mainly to solution chemistry limitations. In addition we present data for similar cells that worked for periods between 3 and 15 months under mid-European climate conditions. While some variability was observed, several of the cells suffered not at all, or only slightly. The stability of the photoelectrodes under these conditions is ascribed mainly to the well-insulated cells used, which ensure operating temperatures under solar illumination up to 40 °C above the ambient temperature.