Solar Electricity
BACKGROUND OF PHOTOVOLTAICS
A diagram of a p-n junction photovoltaic (PV) solar cell is shown in Figure 66. The solar
spectrum at air mass 1.5 (AM1.5) (solar intensity at Earth’s surface with sun at 42º elevation
from the horizon) is shown in Figure 67a; the maximum conversion efficiency of single-band-
gap solar cells as a function of the semiconductor band gap, assuming full electron-phonon
relaxation, is shown in Figure 67b.
Figure 66 A p-n junction PV solar cell