Studies and Reports > 2025 Biennial Report > Transmission Projects Report 2025

6.3   Northwest Zone

6.3.1 Needed Projects

The following table provides a list of transmission needs in the Northwest Zone. As explained in Section 6.1.1, even though Minnkota Power Cooperative is not a member of MISO, some of its planning work is done by MISO. A MTEP Project Number is provided for those Minnkota projects reported in the MTEP reports.

MPUC Tracking Number: 2015-NW-N7

Utility: Minnkota Power Cooperative (MPC)

Project Description: The scope and schedule of the project has changed to increase reliability to a larger number of area loads.
A new 69 kV line from Richwood Distribution Substation to Oakland Distribution Substation (with conversion of White Earth distribution substation onto the 69 kV system) has been deemed necessary sometime in the future. The proposed project includes 20.0 miles of transmission line work (all new line) and a potential conversion of White Earth 41.6 kV to 69 kV. Previously, this project contained additional transmission in the Erie and Audubon areas; however, that has been moved to project 2019-NW-N5 for administrative purposes.

Need Driver: In response to a neighboring system’s request, a new transmission line and substation conversion are being planned for the White Earth Substation. The intent is to transfer load off their system that has grown beyond available back-up capacity. Additionally, a member cooperative has requested service improvements for Richwood and Oakland Substations.

Alternatives:

Transmission Alternatives

There are several transmission alternatives being considered as part of these load transfers. In a previous Biennial Report, the preferred alternative was a 115 kV line and a substation conversion was the preferred project. However, that project was dismissed in favor of a looped 69 kV line.

The alternatives involve further investigation of a Mahnomen/Ulrich 115 kV load tap (the project that was originally proposed). Alternatives may also include parts of the project described (solely Richwood-White Earth or White Earth-Oakland. Investigations are ongoing, and these alternatives will be compared with the proposed transmission line options.

Non-Wires Alternatives

Non-transmission solutions such as battery backup are being investigated. The transmission plan may be changed if these investigations provide equally cost-effective projects that are robust.

Analysis: Reliability impacts from the new transmission lines are currently evaluated in the annual MTEP assessments (in terms of forecasting the existing White Earth load). Impacts to the bulk power system are not the reason for these projects. Limitations of the 41.6 kV transmission and member systems are the reason for the transmission projects (and load transfers).

Schedule: The study efforts mentioned above determined that the new transmission lines do not have a strict completion date. A schedule will be developed as definite plans are determined.

General Impacts: This project is primarily rural in location. The route will have to navigate around some lakes, forested areas, and potentially some reservation land within the area. Assuming a one-hundred-foot right-of-way, the project area will be nearly 275 additional acres (some existing transmission may be used for the project), but the affected farmland should only be about 15 acres, assuming some general estimates on electrical poles and farmland equipment navigation. No notable environmental, human, or health concern exists beyond the aforementioned new transmission. This project is still in its early stages of planning, so all this information is subject to change.

This project may require a short-term project crew. If so, this may bring some business to the area in the form of room and/or board. In terms of local government benefits, it is possible that permit costs may be enforced on this project, but this is determined on a case-by-case basis. Also, some landowners may receive income as a result of this project, and the income may be taxable.

This project is the result of a reliability measure and will probably not have a substantial or lasting impact on the community in terms of the environment or health. It will likely impact some farmland; however, it should only amount to about 15 acres, as stated in the environmental considerations.

Erie/Audubon Alternate Service

MPUC Tracking Number: 2019-NW-N5

Utility: Minnkota Power Cooperative (MPC)

Project Description: From the planned Erie Jct. 230/115 kV substation which taps the Audubon- Hubbard 230 kV line, a new 69 kV or 25 kV 7-mile line with associated transformer will be constructed to MPC’s Erie distribution substation.

In order to provide alternate service to MPC’s Audubon distribution substation, an optional conversion of OTP’s Oak Lake-Erie Jct. 41.6 kV line may be converted to 69 kV. This line is part of a previous project (2015-NW-N7) and there is some overlap between these projects.

Need Driver: There is about 10 MW of load in the Detroit Lakes, MN area served by one substation (Erie) on the OTP 41.6 kV system. Extended outage times have been required for planned maintenance and emergency repairs because no alternate source is available. This is a concern for the Detroit Lakes, MN area. Low load management signals are also a concern.

Alternatives:

Transmission Alternatives

Initial project alternatives included a second transformer at Ulrich, an Audubon- Christensen 69 kV line, or Ulrich 69 kV capacitors. All of these failed to provide fully redundant service to Audubon and Erie. Several options exist to provide similar service; however, they are not as cost effective. These include:

• Normal 41.6 kV service from Erie Jct. 230 kV with backup service from Ulrich (or Audubon)
• Normal 41.6 kV service from Audubon, alternate 41.6 kV service from new load tap.
• Normal or alternate 25 kV underground service from Erie Jct. 230 kV

Non-Wires Alternatives

Battery backup for use as a non-wire alternative was explored but was found to be far less cost effective.

Analysis: Reliability impacts from the new transmission lines are currently evaluated in the annual MTEP assessments (in terms of forecasting the existing Audubon and Erie area loads). Impacts to the bulk power system are not the reason for these projects. Limitations of the 41.6/69 kV transmission and member systems are the reason for the transmission projects (and load transfers).

Schedule: This project is budgeted for completion in 2026 to coincide with the construction of the Erie Jct. load tap (2009-NW-N2). A schedule will be developed as definite plans are determined.

General Impacts: This project is primarily rural in location. The route will have to navigate around some lakes, forested areas, and potentially some reservation land within the area. Assuming a one-hundred-foot right-of-way, the project area will be nearly 121 additional acres (some existing transmission may be used for the project), but the affected farmland should only be about 7 acres, assuming some general estimates on electrical poles and farmland equipment navigation. No notable environmental, human, or health concerns exist. This project is still in its early stages of planning, so all of this information is subject to change.

This project may require a short-term project crew. If so, this may bring some business to the area in the form of room and/or board. In terms of local government benefits, it is possible that permit costs may be enforced on this project, but this is determined on a case-by-case basis. Also, some landowners may receive income as a result of this project, and the income may be taxable.

This project is the result of a reliability measure and will probably not have a substantial or lasting impact on the community in terms of the environment or health. It will likely impact some farmland; however, it should only amount to about 20 acres, as stated in the environmental considerations.

Silver Lake Transformer Replacement

MPUC Tracking Number: 2023-NW-N2

Utility: Great River Energy (GRE)

Project Description: Replace existing 230/41.6 kV transformer with a new 230 kV/41.6 kV 56 MVA rated transformer and install 2-41.6 kV breakers

Need Driver: The addition of two-line termination 41.6 kV breakers is needed to prevent tripping at the Silver Lake substation during line faults.

The Silver Lake transformer plays a critical role in providing reliable electric service across a wide area. The existing transformer, manufactured in 1974, has reached the end of its useful life and has experienced failures, raising reliability concerns. Replacing the current unit with a new transformer that is designed to provide additional capacity to support growth in the area was determined to be the most effective and reliable solution.

Alternatives:

Transmission Alternatives

No lower-cost transmission alternative was identified.

Non-Wires Alternatives

The Silver Lake transformer project is a direct replacement necessary to maintain reliable service in a wide area. Non-wires alternatives were not considered viable, as they are typically not a substitute for end-of-life equipment replacements.

Analysis: The replacement transformer will allow GRE to address reliability concerns associated with the existing aging unit, which has had failures and lacks the capacity to support economic development in the area. The proposed transformer will include additional capacity to accommodate growth in the area.

Schedule: This project is planned to be in service by January 2028.

General Impacts: This project is located on GRE owned property. Construction is expected to be completed in 6 months. During this time, GRE and/or their contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated.

Cormorant Junction – Tamarac – Pelican Rapids (LR-PC) Line Rebuild

MPUC Tracking Number: 2021-NW-N3

Utility: Great River Energy (GRE)

Project Description: Rebuild GRE LR-PC 115 kV line between the Cormorant Junction switch and Pelican Rapids substation.

Need Driver: The existing line has poor reliability and is scheduled for replacement due to its age and deteriorating condition. This transmission line has historically experienced congestion issues, impeding the integration of renewables into the transmission system. The rebuild will increase capacity, ensure a reliable service and create opportunities for interconnection or transfer of generation within the transmission system.

Alternatives:

Transmission Alternatives

This project is driven by the age and condition of the existing transmission line. The only viable solution to address the reliability concerns associated with this critical transmission line, which serves a large area is to replace it with new. This replacement provides an opportunity to resolve other long-standing issues associated with the line’s characteristics, such as congestion and limitations on integrating renewable resources into the grid. No additional alternatives were considered.

Non-Wires Alternatives

Non-wires alternatives were not considered viable for this project due to the nature of the need for this project. The existing transmission line has a low capacity for the current system and in need of replacement due to its age and deteriorating condition. As a main transmission corridor connecting multiple sources serving a wide area, this line plays a critical role in delivering electric service, making non-wires solutions unsuitable as an alternative. Additionally, the line has historically experienced congestion, which hinders the integration of renewable energy into the grid. Rebuilding the line will not only restore reliability but also enhance capacity, enabling future interconnections and transfers of renewable generation. Addressing the issues associated with this transmission line requires physical infrastructure upgrades that cannot be met by non- wires alternatives.

Analysis: The line rebuild project is intended to address the historical reliability issues stemming from the line’s age and condition. Furthermore, the increased capacity of the new line will enable interconnection of renewable resources into either the distribution or transmission systems, addressing previous congestion concerns.

A power flow study was performed and found that the line rebuilds do not cause any adverse impacts to the transmission system.

Schedule: The project is planned to be in service by Winter 2030.

General Impacts: The project will be constructed on the existing 115 kV transmission line from Cormorant Junction switch to Tamarac substation to Pelican Rapids substation. The project is located in predominantly agricultural lands. Construction is expected to be completed in 6 months. During this time, GRE and/or their contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated. The right-of-way will be restored following construction.

Otto Substation Area Rebuild

MPUC Tracking Number: 2025-NW-N1

Utility: Great River Energy (GRE)

Project Description: This project is a new interconnection for Lake Region Electric Cooperative (LREC) Otto distribution substation to GRE owned Rush Lake-Schuster Lake 115kV line. GRE will install a 3-way 115kV switch and construct a new 2.7-mile 115kV line from the tap switch to the Otto distribution substation.

Need Driver: The Otto substation was originally constructed as a temporary facility using wood structures and does not conform to LREC’s standards. As a result, LREC plans to rebuild the substation to meet its standard specifications.

Currently, the substation is served by a 41.6 kV line with subpar reliability performance. Less than three miles north of Otto is a newer and more reliable GRE-owned 115 kV transmission line. LREC is requesting interconnection to this line to improve electric service reliability.

Transmission Alternatives

An alternative to this project was evaluated for LREC to rebuild the Otto distribution substation to 41.6 kV specifications and remain connected to the existing 41.6 kV transmission system. This alternative was not pursued further because the current 41.6 kV system does not meet the improved service reliability needs of the area.

Non-Wires Alternatives

Non-wires alternatives were not considered as this is an existing issue with the reliability of the interconnection of Otto distribution substation.

Analysis: Reliability data for the existing 41.6 kV line serving the Otto distribution substation indicated performance issues, highlighting the need for a more dependable interconnection. While one alternative was to rebuild the Otto substation and maintain the 41.6 kV connection, this option was not pursued further due to the reliability issue with the existing 41.6 kV system serving the substation.
In contrast, a new interconnection to the nearby GRE-owned 115 kV transmission line, located less than three miles from the existing substation offers significantly higher reliability and greater capacity. This line is newer, and part of a more robust transmission network. Interconnecting to this 115 kV system not only addresses the immediate reliability concerns but also positions the Otto distribution substation to support future load growth in the area. From both a technical and economic standpoint, the 115 kV interconnection represents the best value solution for enhancing service reliability to the Otto distribution substation

Schedule: The project is planned to be in service by Fall 2028.

General Impacts:

The project will require approximately 2.7 miles of new 115 kV transmission line to the Otto substation. The project is located in predominantly agricultural lands. Prior to construction, GRE will acquire the necessary right-of-way permits for construction of the project. GRE anticipates acquiring a 100-foot easement to facilitate construction and operation of the line. The preliminary design follows existing road rights-of-way to minimize impacts to nearby residents and environmental features. Prior to construction, GRE will complete a desktop review of environmental features that may be present in the right of way and will work with the appropriate permitting agencies, as required, to minimize impacts during construction. Construction is expected to be completed in 12 months. During this time, GRE and/or their contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated. The right-of-way will be restored following construction. As compared to available alternatives, the project minimizes the length of transmission line through sensitive areas.

J1575 Donaldson South Interconnection

MPUC Tracking Number: 2025-NW-N2

Utility: Otter Tail Power Company (OTP)

Project Description: Build new 3-breaker, 115 kV ring bus on the existing OTP-owned Donaldson – Warsaw 115 kV line, approximately two miles south of Donaldson, to accommodate the interconnection of J1575. J1575 is a 70 MW wind farm from MISO’s 2020 DPP cycle with an executed GIA.

Need Driver: This project is needed to accommodate the interconnection of a planned 70 MW wind farm.

Alternatives:

Transmission Alternatives

This project is required to accommodate the requested Point of Interconnection for a new wind farm. No alternatives were considered.

Non-Wires Alternatives

This project is required to accommodate the requested Point of Interconnection for a new wind farm. No non-wires alternatives were considered.

Analysis: The J1575 interconnection was studied in MISO’s 2020 DPP cycle.

Schedule: The project is planned to be in service by Q3 2028.

General Impacts: This project will be located on a greenfield site along the existing Donaldson – Warsaw 115 kV transmission line, which predominantly runs through agricultural land. Prior to construction, OTP will acquire the necessary land and permits for construction of the project. During construction, OTP and/or contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated.

J1575 Network Upgrades

MPUC Tracking Number: 2025-NW-N3

Utility: Otter Tail Power Company (OTP)

Project Description: MISO’s generator interconnection studies identified overloads on the Donaldson – Warsaw 115 kV line due to the J1575 interconnection, a 70 MW wind farm. This Network Upgrade project will replace one 115 kV breaker and two 115 kV disconnects at OTP’s Donaldson substation. Additionally, one structure on the Donaldson – Warsaw 115 kV line (future Donaldson – Donaldson South 115 kV line) will be replaced to increase sag limits.

Need Driver: This project is needed to enable sufficient generation outlet for a planned 70 MW wind farm.

Transmission Alternatives

This project is required to enable sufficient generation outlet for a new wind farm. No alternatives were considered.

Non-Wires Alternatives

This project is required to enable sufficient generation outlet for a new wind farm. No non- wires alternatives were considered.

Analysis: The J1575 interconnection and related Network Upgrades were studied in MISO’s 2020 DPP cycle.

Schedule: The project is planned to be in service by the end of 2028.

General Impacts: This project will be replacing equipment in the existing Donaldson 115 kV substation, as well as replacing one structure on the Donaldson – Warsaw 115 kV transmission line, which predominantly runs through agricultural land. Prior to construction, OTP will acquire any necessary permits for construction of the project. During construction, OTP and/or contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated. The right of way at the replaced structure will be restored at the end of the project.

Bemidji 115/12.5 kV Substation

MPUC Tracking Number: 2025-NW-N4

Utility: Otter Tail Power Company (OTP)

Project Description: This project involves retiring the 115/69/13.2 kV transformer and the
41.6 kV equipment at the Bemidji 115 kV substation. These retirements will accommodate the addition of a new 115/12.5 kV transformer and a new distribution bus to support existing distribution feeders and multiple new express feeders.

Need Driver: Load growth in Bemidji, MN, has strained the capacity of the distribution facilities in the city. This project adds additional transformer capacity and new express feeders to support backup capabilities and load growth for the city.

Alternatives:

Transmission Alternatives

This project accommodates load growth and improves switching capability on the local distribution system. No alternatives were considered.

Non-Wires Alternatives

This project accommodates load growth and improves switching capability on the local distribution system. No non-wires alternatives were considered.

Analysis: Distribution studies performed in 2024 identified deficiencies in the load serving and backup capabilities of the distribution system in the Bemidji area. These studies resulted in this project, which was found to be the most cost-effective option to support the reliable operation of the city’s distribution facilities.

Schedule: The project is planned to be in service by early 2026.

General Impacts: This project involves the retirement of certain equipment and addition of other equipment at the Bemidji 115 kV substation. The substation is located in a suburban area near US Highway 2 on the West side of Bemidji. No new land is required for the changes within the substation or for the new express feeders. During construction, OTP and/or contractors will be working in the area and will contribute positively to the local economy. No significant traffic impacts are anticipated.

Fargo – St. Cloud – Monticello 345kV Davit Arm Replacement

MPUC Tracking Number: 2025-NW-N5

Utility: Xcel Energy (XEL), Great River Energy (GRE), Otter Tail Power Company (OTP), Minnesota Power (MP), Missouri River Energy Services (MRES)

Project Description: This project replaces select steel davit arms on the Fargo-St. Cloud- Monticello 345 kV Transmission line. Some of the davit arms have defects and need to be replaced.

Need Driver: Condition replacement of steel davit arms on Fargo-St. Cloud-Monticello 345 kV Transmission line.

Alternatives:

Transmission Alternatives

This project replaces existing defective assets, so no other alternatives were evaluated.

Non-Wires Alternatives

This project replaces existing defective assets, so no non-wires options were evaluated.

Analysis: Physical analysis of the structures revealed davit arms that are defective. For safety and integrity of the davit arms, they must be replaced with non-defective arms.

Schedule: The project is planned to be in service by September of 2030.

General Impacts: No significant impacts are anticipated as this is an existing circuit with the majority of the structure will remain as is, with only replaced davit arms.

6.3.2  Completed Projects

The table below identifies projects that have been completed since our 2023 report.