Each one is about the size of a garage door.<\/p>\n
Two panes of glass on a steel post, a small motor on each axis, and a controller that knows where the sun is and where the target is.<\/p>\n
Alone it is a curiosity.<\/p>\n
Put enough of them on a desert floor and aim every one at a single point, and you have close to 600 acres<\/strong> of glass working as one lens.<\/p>\n The target is a boiler.<\/p>\n Everything about the design is mechanically honest<\/strong>, and for a decade it did more or less what the drawings said it would, which turned out not to be the question that mattered<\/strong>.<\/p>\n A photovoltaic panel makes electricity directly and cannot store it.<\/p>\n Sunlight hits silicon, electrons move, and the moment the light stops the output stops, which leaves a battery as the only way to shift any of it into the evening.<\/p>\n Concentrating sunlight makes heat instead.<\/p>\n Heat can sit in a tank of molten salt for hours and still spin a turbine after dark, which is the one thing the mirror approach could do that silicon could not<\/strong>.<\/p>\n This plant was built without that.<\/p>\n The mirrors here boil water directly and the steam goes straight to the turbine, so when the sun goes behind a cloud the output falls with it and nothing is banked<\/strong>, which surrendered the single advantage<\/strong> the technology had.<\/p>\n The site covers about 3,500 acres of the California desert near the Nevada line.<\/p>\n On it stand 173,500 heliostats<\/strong>, each carrying two mirrors, arranged in rings around three towers of roughly 459 feet.<\/p>\n Rated output is 392 megawatts.<\/p>\n That made it the largest plant of its kind anywhere when it started up in February of 2014, built for 2.2 billion dollars<\/strong> with a 1.6 billion dollar<\/strong> federal loan guarantee behind it.<\/p>\n The site was never quiet either.<\/p>\n Construction ran from late 2010 to early 2014 across ground that had to be cleared of desert tortoises first, at a scale that made the project a permitting case study before it made a single kilowatt hour.<\/p>\n Anyone driving to Las Vegas has seen it.<\/p>\n The whole field sits beside the interstate, and the towers are bright enough at midday to be uncomfortable to look at from the road.<\/p>\n The contract asked for about a million megawatt hours a year.<\/p>\n The best year it ever managed was 856,301 megawatt hours<\/strong>, in 2020, and the first year of operation delivered under 40 percent of what had been expected.<\/p>\n The design assumed a capacity factor of 28.5 percent.<\/p>\n Actual performance ran nearer 24 percent<\/strong>, which sounds like a small gap until it is multiplied across a thirty year contract.<\/p>\n Then there is the price.<\/p>\n The power sells at more than 13.5 cents<\/strong> a kilowatt hour, while unsubsidized utility scale panels now come in between 3.8 and 7.8 cents, so the panels are not half the price but closer to a third.<\/p>\n The utility and the owners agreed to end two of the three contracts thirteen years early.<\/p>\n The state commission rejected that agreement on the fourth of December last year, unanimously and without prejudice<\/strong>, which means it can be brought back.<\/p>\n The reason was not sentiment.<\/p>\n Ratepayers have already paid, the resolution<\/a> notes, more than 333 million dollars<\/strong> for transmission built to serve this plant, and switching it off risks stranding more than the termination would save.<\/p>\n Reliability did the rest of the work.<\/p>\n Federal policy shifts have made new project build out uncertain, demand from data centers is climbing, and the commission decided it would rather keep expensive generation<\/strong> than lose it with nothing named to replace it.<\/p>\n The Pulse covered that rejection when the regulator<\/a> handed the deal back.<\/p>\n The loan has not been fully repaid.<\/p>\n An internal audit puts the outstanding figure at roughly 780 million dollars<\/strong>, a number neither the owners nor the department has confirmed publicly.<\/p>\n The birds are the other open file.<\/p>\n Estimates of annual mortality from collisions and from the concentrated beam itself have ranged from 3,500 to 6,000<\/strong>, and that toll was part of why the federal side supported closing it.<\/p>\n The technology itself is not the loser here.<\/p>\n Towers with storage do exactly what this one could not, as a Chinese field of 12,000 mirrors demonstrates by running after dark<\/a> for eight hours at a stretch.<\/p>\n The utility can file again if a replacement is ever named, which is what the trade press<\/a> reads as a technology shift rather than a retreat from solar.<\/p>\n Until then the field keeps tracking.<\/p>\n Every one of those motorized mirrors<\/strong> still turns through the day, aimed at a boiler nobody wants the output from, under a contract nobody is allowed to cancel.<\/p>\n","protected":false},"excerpt":{"rendered":" Each one is about the size of a garage door. Two panes of glass on a steel post, a small motor on each axis, and a controller that knows where the sun is and where the target is. Alone it is a curiosity. Put enough of them on a desert floor and aim every one … Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":35317,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"operators pointed 347","rank_math_title":"Operators pointed 347,000 motorized mirrors at three towers in the Mojave for a decade, and the flat panels they were built to beat make power for roughly a third of what those mirrors charge","rank_math_description":"The Ivanpah solar plant covered 5 square miles of Mojave Desert with 347,000 tracking mirrors, then regulators blocked its closure as flat panels cut its","footnotes":""},"categories":[8],"tags":[],"class_list":["post-35315","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-energy"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/35315","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=35315"}],"version-history":[{"count":1,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/35315\/revisions"}],"predecessor-version":[{"id":35724,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/35315\/revisions\/35724"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/35317"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=35315"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=35315"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=35315"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Why concentrating light was supposed to win<\/h2>\n
What is standing out there<\/h2>\n
The numbers it was measured against<\/h2>\n
The regulator refused to let it close<\/h2>\n
What is still unresolved<\/h2>\n