About four years after its groundbreaking and after the installation of 173,000 mirrored heliostats, the world's largest concentrating solar energy project went online this month near the California-Nevada border.
The Ivanpah Solar Electric Generation System, located in the Mojave Desert 40 miles south of Las Vegas, has been called "the Hoover Dam of Solar Power," and I believe the name is apt. Like Hoover Dam, the Ivanpah project is the result of a public-private partnership. It was backed by Department of Energy loan guarantees, and was developed by BrightSource Energy and Bechtel. Private investors included Google Inc. and NRG Energy.
Functionally, the project generates power using thousands of computer-controlled mirrors, positioned radially around a trio of collector towers. The heliostats then focus sunlight on a trio of BrightSource solar power towers in the center of the arranged mirrors, producing steam in a boiler and then spinning turbines to make electricity.
One way Ivanpah is unlike the Hoover Dam project is that large poured concrete dams had been before and used to generate power. The CSP technology Ivanpah uses is regarded by some as unproven, but Ivanpah is proving that the technology can be used on a massive, multi-megawatt scale.
One of the biggest criticisms of solar technology in general — not just CSP — is that the sun does not always shine, so how can utilities and communities rely on solar plants as generation assets? The Ivanpah project's CSP technology could address this question by employing thermal energy storage using molten salt as a medium. However the project does not, at this time, have any energy storage capacity or plans to implement any.
Perhaps Ivanpah could serve as an inspiration to other project developers in the U.S. and elsewhere to bring CSP and other complementary technologies such as molten salt energy storage together to make the next generation of utility-scale solar power available widely and around the clock.