The photoelectric effect is the physical phenomenon of turning light into electricity. It was discovered by Alexander Edmond Becquerel almost two centuries ago in 1839. However, it was not until 1954, over a century later, that the first silicon photovoltaic (PV) cell was fabricated by Bell Labs. Between the early 1950s and late 1970s, photovoltaic modules were used for specialized government applications that could absorb their high manufacturing and material costs. A catalytic event was required to change the energy market and make PV a competitive resource. That catalysis occurred in 1973 when the United States underwent its first energy crisis resulting from an oil embargo from the Middle East. These advancements in PV cell efficiency can be described by sigmoidal expressions. Gompertz and logistic curves are the most popular in economic theory.