On Friday, ReWire reported on a confusing contradiction concerning the world's largest concentrating solar project in the Mojave Desert. Though press reports indicated the Ivanpah Solar Electric Generating System went online, figures from the state's grid operator showed that California'a solar thermal power plants generated almost no power during the month of January.
Today, we can report that documents from the California Independent System Operator (CaISO,) which runs most of the state's grid, may shed some light on the apparent discrepancy. While the Ivanpah Project was indeed scheduled to go online on December 30, the project spent the entire month of January with at least one of its units going through unplanned downtime every single day.
To sum up daily reports on the state's power plants' operational status filed by CaISO, the Ivanpah project essentially went from planned to unplanned outage status rather than going online.
The daily reports, with the cumbersome title Curtailed and Non-Operational Generating Units in California, are filed each day at 3:15 in the afternoon. They list which of California's 1,000-plus power plants are offline at the time of the report.
It's important to note that listing on the report doesn't necessarily mean the plant in question was down all day: a brief outage running from 2:30 to 4:00 in the afternoon would put a power plant on the list, even though it might have been producing power just fine for the other 22.5 hours that day.
That said, 3:15 p.m. is right in the middle of the potential peak output for a concentrating solar thermal plant like Ivanpah, so even a transitory outage on one day is something operators would likely rather avoid.
And having a string of days with outages during that peak solar time would seem to indicate a serious problem indeed.
Th controversial Ivanpah plant, built over the last three years on about 4,000 acres of public land near the Mojave National Preserve, uses hundreds of thousands of billboard-sized mirrored heliostats to focus solar energy on boilers atop three 450-foot towers. Probably unsurprisingly for new technology, the plant has been plagued by problems ranging from a surprising number of Threatened desert tortoises on the site, to apparent solar flux injury to migrating birds, to a series of small fires that broke out when operators first aimed heliostats at the towers.
Now that the project's completed, with a formal opening ceremony scheduled for the second week in February, the project has almost inadvertently been designated as an experimental solar flux wildlife laboratory. Designer BrightSource Energy has asked the California energy Commission to suspend hearings on its larger Palen Solar Electric Generating System until data on wildlife injuries from Ivanpah can be collected and analyzed.
But if CaISO's outage reports are any indication, that data may be harder to gather than anticipated. According to those reports, there were only two days during the month of January where the project had two of its units apparently online at 3:15 p.m. Unit 1, the first of the project's three units to be completed, was offline at 3:15 every day in January, but on January 12 and 16 it was the only unit going through an unplanned outage. Unit 2 was online at 3:15 on five days in January, and offline on the remaining 26, Unit 3 had the best record for January, with eight days in which it wasn't reportedly offline at 3:15 p.m.
That works out to an effective 79 percent downtime rate for the plant as a whole, as reflected in the CaISO outage reports.
CaISO doesn't gather or provide information to explain any plant's particular outage, and plant operator NRG has still not responded to our information requests. A description of the duration and cause of the reported outages may be forthcoming in the January Monthly Compliance Report for the project, which Ivanpah's operators should be filing with the California Energy Commission sometime in February. Whether that report details routine glitches of the kind you'd expect in a newly built plant, or something deeper, it should prove interesting reading.