After a deadly tornado devastated the US state of Iowa, destroying ten wind turbines, social media posts expressed doubts about the reliability of this type of energy in places prone to extreme weather conditions. But only a small fraction of the turbines in the Midwestern state were affected, and officials and an engineer told AFP the damage was just as intense. it’s rare.
“This is what tornadoes do to wind turbines,” a May 23, 2024 Facebook post it says linking to a video of a wind turbine being it hit in half for a tornado that claimed the lives of at least five people in Iowa.
Similar claims question why a tornado-prone location would support wind farms spread across X here, here It is here as residents were searching damage in Adair and Adams counties.
Iowa It depends largely in renewable energy and is the second largest producer of wind energy in the United States after the state of Texas (archived here).
Tornadoes do impact the state and local media reported that the May 21 storm destroyed ten wind turbines (archived here It is here), but experts said this level of damage is atypical.
“For the record, that’s 10 of the state’s 6,757 turbines, according to the Energy Information Administration,” said Kanan Kappelman, spokesman for the Iowa Economic Development Authority.
“It is unusual for wind turbines to suffer damage from tornadoes,” she told AFP on May 23.
Central American Energywhich has operated in the state since 2004, also said that this storm caused an “unprecedented impact” on its wind fleet.
“We have only had one other case of a wind turbine collapse, which was also caused by a tornado,” company spokeswoman Tina Hoffman told AFP on May 24.
Videos of turbines withstanding tornadoes were also captured (filed here).
Powerful winds
Tornadoes are measured in Improved Fujita scale or EF scale and rated based on wind speed and damage (archived here).
The National Weather Service he said confirmed “EF-4 damage in Greenfield, Iowa, EF-3 damage in NW Adams County, and EF-2 damage from two tornadoes: in Polk, Story County, and near Arbor Hill” (archived here). Maximum wind speeds in the EF-4 tornado were estimated at 175-185 miles (281.6-297.7 kilometers) per hour.
Manufacturers project wind turbines to sustain extreme weather conditions, including severe storms and high winds, but Hoffman said, “Few structures can withstand the direct impact of a powerful tornado like the one we experienced on Tuesday.”
She said several of the company’s turbine sensors recorded wind speeds in excess of 100 miles per hour as the tornado approached, before the towers were destroyed.
Sanjay Raja Arwade (filed here), professor of civil engineering at the University of Massachusetts Amherst, told AFP that the probability of a tornado directly impacting a tower is very high. low.
“TThe amount of land area affected by the impact of a given tornado is relatively small,” he said on May 24.
Turbine operators also take precautions, such as designing the systems to automatically shut down at very high wind speeds (filed here).
Legislation in Iowa requires Wind turbines must be placed at a minimum distance from inhabited areas in order to reduce the risk to human safety in the event of a catastrophic event (archived here).
But turbines, “like any other piece of infrastructure, including buildings, can be damaged by the direct impact of a tornado,” an Energy Department spokesperson told AFP on May 23.
By the end of April, reports of tornadoes in the United States had already largely exceeded the 1991-2020 annual averagesetting the stage for one of the most active years on record (archived here).
But Arwade said, “If you look at all the wind turbines in Texas, Oklahoma, Nebraska, Iowa, all the Great Plains states, the number of those turbines that will be impacted in a given tornado season is small. incorporating the effects of climate change, it will continue to be small.”
The AFP has debunked other claims about wind turbines, here It is here.
