Otter Tail Power Company IRP spans three states, adding LNG, solar and wind by 2028

Published on April 04, 2023 by Chris Galford

© Otter Tail Power Co.

In filing its latest Integrated Resource Plan (IRP) with regulatory commissions in Minnesota, North Dakota, and South Dakota, Otter Tail Power Company laid out ideas to cover its portfolio through 2036, including specific ideas for the next five years.

In the immediate, this would preferably take the form of a new on-site liquefied natural gas (LNG) fuel storage site at Astoria Station in 2026, approximately 200 MW of solar generation by 2028, repowering four existing wind farms and potentially, a withdrawal of the company’s 35 percent ownership interest in North Dakota’s Coyote Station if it would have to make a large, non-routine capital investment into the coal-fired plant.

“Our updated preferred plan adds more renewable generation resources to our portfolio than our prior plan,” said Brad Tollerson, vice president of energy supply at Otter Tail. “With respect to Coyote Station, our analysis still supports withdrawal from our ownership interest if we are required to make a large, non-routine capital investment to operate the plant or comply with regulatory mandates. That was the case in our initial preferred plan and remains the case with today’s update. Where our Coyote Station analysis differs from our initial filing is that the mix of uncertainties and risks our customers face in the current planning environment supports retention of Coyote Station in our generation portfolio if we’re not required to make a major capital investment in the plant.”

An initial IRP filing was made in September 2021. According to Tollerson, various changes altered the planning landscape and made adjustments to the IRP necessary. Intervenors will now have four months to analyze the updated plan and offer feedback in Minnesota, with a hearing to likely follow near the year’s end. In North Dakota, a consultant will review the modeling and offer thoughts on the reasonable nature of the preferred plan. South Dakota has no formal IRP requirements or proceedings.