Is solar thermal electric generation dead? The Department of Energy last week settled with bankrupt Tonopah Solar Energy in Nevada in a deal that has to be blessed by bankruptcy court to recover $200 million of a $1 billion project that got a $737 million loan from the agency in 2011.
The Crescent Dunes plant, a nominal 110-MW solar power tower in the Nevada desert had severe technical problems, never came close to achieving a hyped 50% capacity factor (it’s short lifetime capacity factor was about 20%), and has been offline since April 2019. DOE spokeswoman Shaylyn Hynes said, “This project has consistently faced technical that have proven difficult to overcome. The department’s decision was made after years of exhausting options within our authority to get the project back on track, given the significant taxpayer investment the prior administration committed to this project.”
The Crescent Dunes project used “10,347 heliostats that collect and focus the sun’s thermal energy to heat molten salt flowing through an approximately 656-foot (200 m) tall[32] solar power tower. Each heliostat is made up of 35 6×6 feet (1.8 m) mirror facets, yielding a heliostat overall usable area of 1,245 square feet (115.7 m2). Total solar field aperture adds up to 12,882,015 square feet (1,196,778 m2). The molten salt circulates from the tower to a storage tank, where it is then used to produce steam and generate electricity.” The project was designed to store about 10 hours of generation, which could be used at night.
The 1,600-acre project was built on federal land and went into commercial operation in 2015, with a contract to supply power to local electric utility NV Energy as its only customer. NV Energy killed the contract in October 2019 for failure to deliver power. According to E&E News, DOE is still owed some $425 million, with the last payment to the government coming in July 2013.
When the Obama-administration DOE made the award in September 2011, the agency said, “Crescent Dunes is expected to generate 482,000 megawatt-hours of clean energy per year while preventing 279,000 metric tons of carbon dioxide emissions annually.” When the department announced its potential $200 million recovery, Bloomberg Businessweek commented, that the project “was obsolete before it ever went online.”
Ironically, DOE made the award just three weeks after another solar project, Solyndra, crashed and burned technically and financially, costing the feds some $500 million. Solyndra won a highly-touted $535 million DOE loan in 2009 and filed for bankruptcy in 2011.
In January, Greentech Media reported, “America’s concentrated solar power companies have all but disappeared.” The publication, an advocate of all things solar, observed, “CSP has developed a bad reputation in the U.S., not just because of problems at Crescent Dunes but also from low capacity factors overall and largely exaggerated reports of bird deaths at power-tower plants such as those developed by SolarReserve and another U.S. firm, BrightSource Energy.
But the biggest challenge facing CSP, not just in the U.S. but also in the rest of the world, is the plummeting price of solar PV.”
Longtime energy journalist and analyst Robert Bryce commented on the Crescent Dunes fiasco, “Stick a fork in solar thermal. It’s done.”
— Kennedy Maize