The sun provides a virtually unlimited, clean, and free fuel at a price that never changes. Solar farms take advantage of that resource, with large-scale arrays of hundreds, thousands, or in some cases millions of photovoltaic (PV) panels. They operate at a utility scale like conventional power plants in the amount of electricity they produce, but dramatically differ in their emissions.
Solar farms can be found in deserts, on military bases, atop closed landfills, and even floating on reservoirs, deploying silicon panels to harvest the photons streaming to earth. Inside a panel’s hermetically sealed environment, photons energize electrons and create electrical current—from light to voltage, precisely as the name suggests.
Bell Labs debuted silicon PV technology in 1954. At that time, photovoltaics cost more than $1,900 per watt in today’s currency. Since then, public investment, tax incentives, technology evolution, and brute manufacturing force have chipped away at the cost of creating PV, bringing it down to sixty-five cents per watt today.
In many parts of the world, solar PV is now cost competitive with or less costly than conventional power generation. In tandem with other renewables and enabled by better grids and energy storage, solar farms are ushering in the clean energy revolution.
Technical summaries for each solution will be available May 1, 2017.