TransAlta Renewables Inc. will take the next two years to replace the foundations at 50 turbines at its Kent Hills Wind Farm in New Brunswick, the company said Jan. 11.

One tower at the plant site collapsed in October 2021, and TransAlta Renewables then took Kent Hills 1, with 32 turbines, and Kent Hills 2, with 18 turbines, offline. They began operating in 2008 and 2010, respectively.

Independent engineering assessments and a root cause failure analysis determined there were deficiencies in the original design of the foundations that led to crack propagation, TransAlta Renewables said.

Replacing all 50 foundations is estimated to cost C$75 million to C$100 million, the company said, and it will take to the end of 2023 to complete. The company is losing about C$3.4 million a month from the sale of the wind farm's output to local utility New Brunswick Power Distribution and Customer Service Corp., a unit of NB Power.

TransAlta Renewables said it will look to recover the repair costs from third parties and insurance.

Also, TransAlta Renewables said it notified BNY Trust Company of Canada, trustee for about C$222 million in outstanding nonrecourse project bonds secured by the Kent Hills 1 and 2 sites, that events of default may have occurred. The company said it will initiate discussions with the trustee to negotiate possible waivers and amendments.

Five turbines added in 2018, called Kent Hills 3, are not affected by the foundation issue, TransAlta Renewables said.

TransAlta Renewables shares dropped nearly 3% in trading on the Toronto Stock Exchange on Jan. 11. The company is majority-owned by TransAlta Corp., whose shares dropped by more than 3% in trading Jan. 11. In midday trading Jan. 12, both were up in heavy activity.