Our Resource Plan identifies research and development projects and the most cost-effective combination of resources for meeting our customers’ needs for reliable electric service during the next 15 years. While this filing is required only in Minnesota (Docket Number 16-386), we develop a strategy for our whole system and file the plan with the North Dakota and South Dakota regulatory commissions.
Our 2017-2031 Resource Plan, approved by the Minnesota Public Utilities Commission (MPUC) in April 2017, gives us authority to add up to 250 Megawatts (MW) of natural gas, up to 300 MW of wind, and up to 30 MW of solar resources. To execute our resource plan, we're adding the Merricourt Wind Energy Center and Astoria Station to our resource mix. And, as solar prices continue to drop, we’ll likely build or purchase solar resources in the 2022 timeframe.
The graphs below represent the energy we serve our retail customers.
*The majority of our purchased power comes from Midcontinent Independent System Operator, Inc. (MISO). The makeup of our 2019 purchased power as shown on MISO's website is 41% coal, 31.2% natural gas, 16.9% nuclear, 7.8% wind, 1.8% hydro, and 1.2% other (includes solar).
Renewable Portfolio Standards
Each of the states we serve has enacted either a Renewable Portfolio Standard or a voluntary Renewable Energy Objective. Minnesota requires 20% of the energy we serve our Minnesota retail customers to come from renewable resources by 2020 and 25% by 2025. The state also requires 1.5% of our energy for Minnesota retail customers to be generated by solar resources by 2020. We're well positioned to comply with Minnesota's renewable energy standard, with over 15% of our resources coming from renewables today. That percentage will increase when the Merricourt Wind Energy Center is energized in 2020. Additionally, we've purchased Solar Renewable Energy Credits to comply with the solar energy standard through 2021 and anticipate building or purchasing a large scale solar project by 2022. North Dakota and South Dakota implemented voluntary Renewable Energy Objectives for 10% of all electricity sold at retail to be obtained from renewable resources by 2015. We met those objectives.
We operate three coal-fired plants that produced about 46% of the energy our customers used in 2019.
Location: Big Stone City, SD
Age: On line since 1975
Capacity: 475 MW (Net Dependable Capacity)
2019 net energy output: 2,619,088 MWh
2019 availability: 91.43%
Fuel source: Subbituminous
- 53.9% Otter Tail Power Company
- 23.4% NorthWestern Energy
- 22.7% Montana-Dakota Utilities Co.
Location: Beulah, ND
Age: On line since 1981
Capacity: 432 MW (Net Dependable Capacity)
2019 net energy output: 2,061,699 MWh
2019 availability: 67.67%
Fuel source: Lignite
- 35% Otter Tail Power Company
- 30% Northern Municipal Power Agency
- 25% Montana-Dakota Utilities Co.
- 10% NorthWestern Energy
Location: Fergus Falls, MN
Age: Unit 2 on line since 1959, Unit 3 on line since 1964
Capacity: 141 MW (Net Dependable Capacity)
2019 net energy output: 313,359 MWh
2019 availability: 84.4%
Fuel source: Subbituminous
Ownership: 100% Otter Tail Power Company
Hoot Lake Plant Retirement
In 2012 we completed a baseload diversification study with a focus on evaluating retirement and repower options for our 1950s-era Hoot Lake Plant in Fergus Falls, Minnesota. The aging plant no longer is part of an economical resource plan, and we’ll retire the plant in May of 2021. We’re proud of Hoot Lake Plant’s legacy and the vital role it has played both in our company’s and community’s history. We're encouraging and assisting, when possible, the employees currently at Hoot Lake Plant to continue their career with our company. And we’ve been, and will continue to be, actively involved with the City of Fergus Falls to manage the impact of the planned retirement.
The Merricourt Wind Energy Center and Astoria Station are part of our company’s plan to prepare for the retirement of Hoot Lake Plant, meet our customers’ future energy needs, and replace expiring power purchase agreements.