This article is part of the Energy.gov series highlighting the “Top Things You Didn’t Know About…” Be sure to check back for more entries soon.
10. Concentrating solar power (CSP) technology involves using mirrors, sometimes in the hundreds of thousands, to reflect sunlight and collect solar heat to generate electricity. A single CSP plant can generate enough power for about 70,000 homes -- making it a major player of the utility-scale solar market. For more CSP technology basics, watch our video Energy 101: Concentrating Solar Power.
9. Legend has it that the Greek scientist, Archimedes, first made use of concentrated sunlight by employing the reflective properties of bronze shields to set fire to Roman ships during the battle of Syracuse in 212 BC. While experimental recreations have proved such a feat is possible, much doubt still surrounds this story.
8. There are four types of demonstrated CSP technologies. Parabolic trough and linear Fresnel systems focus sunlight onto a linear receiver. The other two technologies -- dish/engine and power tower -- focus sunlight to a point. All of these technologies involve converting sunlight into thermal energy for use in a heat-driven engine.
7. How can solar-generated electricity be consistently available when the sun doesn’t shine around-the-clock? The answer lies in thermal energy storage -- the ability to store the sun’s heat in the form of thermal energy for use when the sun isn’t shining. By incorporating thermal energy storage systems, the cost of power from a CSP plant can actually be reduced and can provide solar power on demand -- even when it’s cloudy or at night.
6. As early as the 1980s, the Energy Department has made strategic investments to demonstrate that large-scale concentrating solar power tower systems are viable. The Solar One project near Barstow, California, paved the way for Solar Two, the world’s first large-scale molten salt power tower facility, launched in 1996. Today, molten salt thermal energy storage technology is widely commercialized in the CSP industry, and both direct steam and molten salt power tower technology are currently being deployed at a global scale.
5. More than 800 megawatts of CSP plants currently operate in the United States. Four new CSP plants will soon increase the total CSP capacity in the United States to 1.8 gigawatts. These new CSP plants will provide enough electricity for nearly half a million homes. Check out our interactive map of America’s CSP plants -- both up-and-running and under-construction.
4. In a CSP system, heat transfer fluids move thermal energy from the solar receiver to the power block, where the heat is used to drive a turbine that generates electricity. The Energy Department is funding research projects to develop new heat transfer fluids that can operate at incredibly high temperatures, of up to 2,350 degrees Fahrenheit, to increase efficiency and decrease costs.
3. The Energy Department’s SunShot Initiative has set aggressive targets to lower the cost of CSP by the end of the decade. The CSP research and development projects funded under SunShot focus on exploring technological innovations for CSP components that will help achieve this goal.
2. The CSP supply chain is overwhelmingly domestic. Most, if not all, materials necessary to build a CSP plant can be found and manufactured here in the United States -- creating job opportunities and driving economic growth. As an example, the supply chain for Abengoa’s Solana recently commissioned project covers 27 states and 90 U.S. companies.
1. Between 11 and 21 gigawatts of CSP could be built and integrated into existing fossil fuel plants in the United States – enough to power to between 3 million and 6 million homes. These hybrid systems improve the efficiency and performance of both resources and help cut carbon pollution -- mitigating the effects of climate change.