The original Bell Solar Battery (photovoltaic panel) is used in an early test in 1955 in Americus, Ga.

In the early 1950s R.S. Ohl discovered that sunlight striking a wafer of silicon would produce unexpectedly large numbers of free electrons. In 1954, G.L. Pearson, C.S. Fuller, and D.M. Chapin created an array of several strips of silicon (each about the size of a razor blade), placed them in sunlight, captured the free electrons and turned them into electrical current. This was the first solar battery.  It could convert only six percent of the sunlight into useful energy. Bell Labs applied this breakthrough technology to provide remote power for improving telephone service.  Solar Cells continue to be used today as a green source of energy and for providing electricity to remote locations. - Source: AT&T web page.