Combining Eq. (10.15) with (10.17) we find
Figure 10.5 shows the bandgap utilization efficiency for three different spectra of the
incident sunlight. For a bandgap of 1.12 eV this efficiency is about η V ≈ 77%.
Figure 10.5: The bandgap utilization efficiency η V for the blackbody spectrum at 6,000 K, and the AM0 and AM1.5
solar spectra.
For the fill factor we take the empirical but very accurate approximation
with v oc = qV oc /k B T. We already discussed this approximation in Eq. (9.3).
Figure 10.6 finally shows the Shockley–Queisser efficiency limit for three different
spectra of the incident light. For the AM1.5 spectrum the limit is about 33.1% at 1.34 eV.
For AM0 it is 30.1% at 1.26 eV.
Figure 10.6: The Shockley–Queisser efficiency limit for the blackbody spectrum at 6,000 K, and the AM0 and AM1.5
solar spectra.