June 11, 2013
Solar cells are unusual in that they were cost-competitive from the get-go. From the Apollo space program to highway signs to lighting for buoys, solar could replace highly expensive power from batteries or other sources and eliminate the need for the construction of electric distribution lines.
When the Institute for Local Self-Reliance was founded in 1974, the first factory producing solar cells for terrestrial applications had just opened in Gaithersburg, Maryland. The cost of solar power was over $3.00 per kilowatt-hour (kWh), com- pared to $0.03 per kWh for grid electricity. The output from that factory the first year was sufficient to power only a few dozen homes. By the late 1980s, the price of solar was low enough that solar cells were finding their way to second homes and remote cabins off the grid. In 1990, the total installed capacity of solar was 200 megawatts (worldwide, with about 25 percent in the U.S.), sufficient to power 4,000 homes. During the ensuing decade, federal and later state incentives for solar ushered in the era of grid-connected solar. By 1999, grid connected solar projects exceeded non-grid application. Read more at Link.