Montana-Dakota Utilities Co. agreed to acquire a 48-MW expansion of the Thunder Spirit wind farm in North Dakota from ALLETE Clean Energy, according to a March 1 news release.
The expansion project will host 16 additional turbines to boost Thunder Spirit's generating capacity to about 155 MW from 107.5 MW, increasing the MDU Resources Group Inc. subsidiary's renewables portfolio to 27% from 22%.
The project is estimated to cost $85 million and is anticipated to go online in late 2018. The project is in Adams County.
Montana-Dakota Utilities originally signed a power purchase agreement with the ALLETE Inc. subsidiary for the expansion but eventually decided to exercise its option to acquire the project after determining it would be more cost-effective for its customers.
The original Thunder Spirit was constructed by ALLETE Clean Energy using 43 turbines and was purchased by Montana-Dakota Utilities in December 2015.
