Solar Cell Theory

Abstract

As a result of comprehensive studies sponsored by NSF and NASA and by the National Academy of Science, it became evident in 1972 that a substantial reduction in production cost to approach 1$/W* and an increase of efficiencies beyond 10% for thin-film and beyond 20% for single crystal solar cells were feasible [1]. With significant government support mainly in the USA, Japan, and Western Europe, rapid progress was made and essentially all technical goals set in 1972 have been achieved and surpassed (thin-film efficiency 12% for CdS/CuInSe₂ and 13% for α-Si, single crystal AMl efficiency 23% for Si and 23% for AlGaAs/GaAs; recent Sicells in concentrators have achieved 27% conversion efficiency) [7]. The economic goal (updated for competing with the increased electric energy generation cost and inflationary devaluation of the dollar) seems to be within reach and large quantities of solar panels sell currently for ~5 $/W. The life expectancies of better Si-panels (conservatively estimated) are well in excess of 20 years.