MidAmerican says turbine blades getting upgrade to improve safety | Donnelle Eller | Des Moines Register | Jan. 21, 2021 | www.desmoinesregister.com
MidAmerican Energy says the manufacturer of roughly 325 of the utility’s Iowa turbines is upgrading equipment to improve the “blades’ resiliency in extreme weather situations.”
The move follows MidAmerican Energy’s decision last fall to take 46 turbines offline while employees checked them for safety. The Des Moines-based company said three blades broke from turbines last year and one in 2019 after direct or nearby lightning strikes. No one was injured in the blade failures.
The company, owned by Warren Buffet’s Berkshire Hathaway, isolated the failures to blades made by Danish manufacturer Vestas. MidAmerican inspected all turbines that had Vestas blades and had experienced similar weather conditions. The utility said it made improvements where they were needed.
Now, MidAmerican says Vestas is upgrading its lightning protection systems on about 325 turbines the utility owns in Iowa. The protection systems are designed to channel the energy from any nearby lightning strikes safely into the ground.
MidAmerican spokesman Geoff Greenwood said Vestas is expected to complete the upgrades by late spring, before the peak lightning season. The turbines being upgraded represent about 10% of the 3,321 MidAmerican operates.