Figure 3. Schematic diagram of the quantified energy losses during photovoltaic operation of the GaInP/GaAs/Ge 3-junction solar cell, made on the base of the measured external luminescence quantum efficiencies.

The working condition of the solar cell was 1-sun AM0 with the maximum output power. The input power of sun light is normalized to 100%, and all the values of the parameters are ratio. Out: Output power of the solar cell. TR: transmission loss, TH: thermalization loss, EM: external emission loss, NR: non-radiative recombination loss, JN: junction loss (the energy loss caused by the voltage drop of the carriers from bandgap voltage to internal voltage of the junction). The values of the energy losses are summarized in Table 2.