The design of multijunction photovoltaic systems for realistic operating conditions

The design of a multijunction photovoltaic system, particularly the choice of the individual bandgaps, is sensitive to the specific operating conditions of the system. Laboratory characterization is typically carried out at a standard temperature, such as 25 °C, using a standard solar spectrum, such as an AM1.5 direct spectrum. In reality, the system should be designed for operation at its anticipated temperature of operation, taking into account the spectral variation of the solar radiation over the course of the day and year. In this paper, the effects of such variations in operating conditions on the performance of different designs are examined.