A recently released study by the National Renewable Energy Laboratory, estimates that the technical potential of photovoltaic cells and concentrated solar power (CSP) in the United States is as much as 200,000 Gigawatts, enough to generate about 400,000 TWh of energy annually.
The report dismisses economic and political impacts on the solar industry and focuses solely on the scientific and engineering limitations. The types of solar power studied in the report were Urban Utility-Scale Photovoltaics, Rural Utility-Scale Photovoltaics, Rooftop Photovoltaics, and Concentrated Solar Power, which is a utility-scale project “in which the solar heat energy is collected in a central location.”
The report broke down each type of solar array:
“The total estimated annual technical potential in the United States for urban utility-scale PV is 2,232 terawatt-hours (TWh). Texas and California have the highest estimated technical potential, a result of a combination of good solar resource and large population.”
Rural Utility Scale PV:
“Rural utility-scale PV leads all other technologies in technical potential. This is a result of relatively high power density, the absence of minimum resource threshold, and the availability of large swaths for development. Texas accounts for roughly 14% (38,993 TWh) of the entire estimated U.S. technical potential for utility-scale PV (280,613 TWh).”
Total annual technical potential for rooftop PV is estimated at 818 TWh. States with the largest technical potential typically have the largest populations. California has the highest technical potential of 106 TWh due to its mix of high population and relatively good solar resource.
Technical potential for CSP exists predominately in the Southwest…. Texas has the highest estimated potential of 22,786 TWh, which accounts for roughly 20% of the entire estimated U.S. annual technical potential for CSP (116,146 TWh).
The report also conducted a state by state breakdown for potential energy from solar sources.
Due to their high populations, large land areas, and ample sunlight, California and Texas are the states best suited to harvest the most solar power, especially from utility-scale projects.
In fact, in California, the National Park Service and NREL, which is a division of the Department of Energy, have outfitted one of America’s most noteworthy locations with 1,300 solar panels as part of an on going effort.
Alcatraz, the notorious prison located on an island of the same name in the middle of San Francisco Bay, is now a tourist hotspot but was once home to infamous gangsters and murders such as Al Capone and “Machine Gun” Kelly. For decades, barges would bring shipments of oil and gasoline used to power the lights and other appliances on the island. Now, however,
“307-kilowatt photovoltaic (PV) array sits on the roof of the main Cellhouse building, attached to two 2,000-amp-hour battery strings and an inverter plant. The new 1,300-panel system produces close to 400,000 kilowatt-hours of electricity a year, reducing carbon dioxide (CO2) emissions by about 337,000 kilograms a year and reducing the time the generator runs from 100% to 40%.”
A major hurdle in installing the solar array was the concerns of historical conservationists that the modern solar panels would destroy the aesthetic of the old and venerated prison. Fortunately, the cells, and an enormous battery system to store power for cloudy days, have been completely hidden from view.
It should also be noted that the funding for this project, more than $3.5 million, came from the stimulus package, The American Investment and Recovery Act. Efforts to outfit Alcatraz with solar panels have existed, off and on, since 1995 and were finally acted upon when the stimulus funds became available.
Since the shipping of fossil fuels to Alcatraz slowed thanks to the photovoltaic cells, the price of electricity on the island has decreased by 5 cents a kilowatt hour.
Efforts like this one taken by NREL show the potential of persistence and creative thinking in installing innovating green ideas and limiting dependence on fossil fuels.