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Wind farms are a pillar of America’s climate change strategy. They now produce over 8% of the nation’s electricity , and their output is expected to nearly double over the next decade. A Facebook post casts wind as a losing proposition. A windmill could spin until it falls apart and never generate as much energy as was invested in building it, a Sept. 16 version of the post says. This qualifies as a zombie claim. In 2019, we found an earlier version False , but it walks again. The image is topped with a striking photo of a wind turbine on fire (it comes from a March 2020 fire in Texas) and gives some details. A two-megawatt windmill is made up of 260 tonnes of steel that required 300 tonnes of iron ore and 170 tonnes of coking coal, all mined, transported and produced by hydrocarbons, the post says. (We corrected several typos in the text.) The post is wrong. From construction to demolition, the energy payback on a windmill can be less than a year . The highest estimate we found was a bit under six years. A cherry picked quote The numbers in the post come from a 2009 collection of essays on climate change and Canada. J. David Hughes, a geoscientist with the Geological Survey of Canada, wrote about the total energy package for wind turbines, a perspective that included how much energy it took to make the turbine, not just the energy it produced when it was operational. The question is: how long must a windmill generate energy before it creates more energy than it took to build it? Hughes wrote. Hughes’s focus was on the need to put turbines in places where the wind blows. At a good wind site, the energy payback day could be in three years or less, Hughes wrote . In a poor location, energy payback may be never. The Facebook post skipped over that sentence, and jumped to Hughes’ warning, that in the wrong spot, a windmill could spin until it falls apart and never generate as much energy as was invested in building it. (There’s a logical breakdown here: If a turbine is spinning, then the wind must be blowing, and the turbine is producing power.) Also, wind turbine technology has changed greatly over the past 10 years, as engineers have developed more efficient models and gained experience in siting windmills. The 2009 material is dated. A windmill’s lifecycle energy story For decades, researchers have been assessing all the steps that go into turning wind into electricity. Study after study has found that when all is said and done, a properly placed turbine nets out positive. A 2016 study from Danish engineers looked at onshore and offshore turbines and wrote, The energy payback time was found to be less than 1 year for all technologies. A group of engineers in Texas did similar work and reported that the payback times for CO2 and energy consumption range from 6 to 14 and 6 to 17 months, with on-shore facilities having a shorter payback. There are many steps in the making of a wind turbine. The raw materials need to be mined, those materials need to be turned into rotors and towers and those parts need to be shipped. It takes energy to install a turbine, and a small bit of energy to operate it. And at the very end — after 20 to 30 years — it has to be dismantled and recycled. Research finds that as much as 86% of the total energy comes in the manufacturing step, although some studies found lower percentages. There are a few key variables, including how long the wind turbine lasts — manufacturing costs are baked in, and the longer a turbine lasts, the more years those costs get spread over. Another key variable is the wind. Turbines may have a predicted output, but the wind determines what really happens. One 2019 study from engineers at the University of Texas at Arlington factored in the wind speeds from a working wind farm in Texas with 200 turbines. It examined in detail the energy it took to move the turbine components from where they were made in Spain to the Lone Star Wind Farm near Abilene, Texas. It also measured the energy it took to get raw materials to the factories in Spain where manufacturing took place. The wind at the Lone Star Wind Farm varies and the researchers used that data to find the actual average wind speed through the year. They calculated a turbine that lasts 20 years will reach a full energy payback in less than six years. Our ruling A viral image said that a wind turbine could never generate as much energy as was invested in building it. The claim cherry-picked a quote from a book and distorted its meaning. Every study of the lifecycle of wind turbines finds that they produce more energy than it took to produce them. Most analyses put the energy payback period at about a year or so. The most conservative, real-world assessment we found calculated that wind turbines in Texas produced more electricity than it took to build them after about six years. We rate this claim False.
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