The US onshore wind farm has taken a hit to its structures after powerful tornadoes directly impacted its wind turbines, including one that burst into flames. Social media has captured terrifying images of the violent tornado ripping through the wind farm, uprooting trees, damaging buildings and sending earth and debris flying through the air.

Source: Youtube

In total, at least 17 tornadoes have been recorded in Iowa alone, as part of a parade of storms that have swept across the US this week, leaving widespread power outages, structural damage and some flooding in their wake.

Community impact

Storms across southwest Iowa destroyed 10 turbines near Greenfield, a town that suffered four deaths and at least 35 injuries from tornadoes and extensive damage. MidAmerican Energy reported that six turbines at two wind farms went down and Oregon-based Vestas said four turbines went down at a wind farm in Adams County.

According to PowerOutage.us, nearly 200,000 homes and businesses in Iowa, Wisconsin and Illinois were without power. Even more outages are expected with Wednesday's storms in the east.

Economic and operational impact

The American press has reported that the damage to wind turbines and wind farms was severe. MidAmerican Energy, which serves nearly two-thirds of Iowa, reported that six turbines collapsed during the storms, mostly at the Orient wind farm.

Vestas, meanwhile, reported that several of its turbines recorded winds of more than 100 mph before sensors stopped communicating. In addition, spokesman Matt Copeman said in an email that several employees ‘have been displaced’ after their homes were destroyed or severely damaged.

Experts indicate that although these incidents are rare, the impact of this tornado was particularly devastating. Tina Hoffman from MidAmerican commented, "We are grateful that no one in the area was injured by the turbine collapse. Our thoughts are with those near Greenfield who lost their lives, as well as many others who were injured or lost their homes due to the same severe storm." She added, "This was an unprecedented impact on our wind fleet, and we have been operating wind farms since 2004."

Evaluation and response

MidAmerican Energy is assessing the damage and power outages caused by the storms and tornadoes. More than 700 customers were left without electricity after the outbreak. Images from storm chasers showed turbines being thrown into the air, circling the tornado before crashing to the ground.

Is the wind industry prepared for these natural events?

Wind turbines are designed to withstand high wind speeds and adverse weather conditions such as tornadoes, hurricanes, and lightning. However, few structures are designed to withstand the direct impact of a powerful tornado like an EF4 or EF5. Jennifer Thompson, a meteorologist with the National Weather Service in Norman, Oklahoma, highlighted the rarity of these events, indicating that although the central U.S. is prone to tornadoes, the coincidence with wind farms is extraordinarily unusual.