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Studies and Reports > 2023 Biennial Report > Transmission Studies

Transmission Projects Report 2023
Chapter 3: Transmission Studies

Transmission Studies

3.1  Introduction

The Commission requires the utilities include in each Biennial Report a “list of studies that have been completed, are in progress, or are planned that are relevant to each of the inadequacies identified” in the Report.16 Since the 2011 Biennial Report, the utilities have broken this chapter up into several subsections, each addressing different types of studies. The same arrangement for reporting the studies is continued in this 2023 Report.

Section 3.2 describes studies completed to either address expansion of the transmission network to provide for generation expansion or address local inadequacy issues (noted with a Tracking Number). Section 3.3 describes ongoing regional studies that focus on expansion of the bulk electric system to address broad regional reliability issues and support expansion of renewable energy in the upper Midwest. Section 3.4 focuses on ongoing load serving studies done to address local inadequacy issues.

The MPUC rules state that the utilities must include in the Biennial Report a copy of “the most recent regional load and capability report of the Mid-Continent Area Power Pool.”17 As the utilities reported in the 2011 Report, however, MISO has taken over most of the planning that occurs in this part of the country. MAPP has not prepared a Load & Capability Report since May 2009. MAPP, in fact, discontinued its existence in October 2015.

Completed Studies

The following studies were completed since the last Biennial Report was submitted in October 2021. Previously completed studies can be found in previous Biennial Reports and are not repeated here. Where specific transmission projects have been identified, a Tracking Number is provided. The Tracking Number identifies the year the project was first considered for inclusion in a Biennial Report and the zone where the project is located.

Study Title

Year Completed

Utility Lead


Worthington Area Study



GRE, ITCM & MRES studied the transmission system in the Worthington area to serve a potential load addition as well as mitigating existing reliability and operational concerns.  See chapter 6, Southwest Zone, Worthington Area Projects.

Barnesville Area



GRE, MRES, and OTP are studying the transmission system in the Barnesville area to address local load serving concerns, and potential reliability benefits for the surrounding load pocket looking out towards the end of the planning horizon. The study is expected to be completed early 2022.

Pilot Knob Area Study



Evaluate long range options for the Pilot Knob area. There is a future need to rebuild the Pilot Knob substation due to age and condition. This study will determine the feasibility of converting the area to 115 kV.

Minnkota Power Cooperative 2022 GFA Load Increase Study



MPC requested an increase in their load limit under several Grandfathered Agreements in OTP’s area. This study was performed to identify potential system needs related to the load increase.




Evaluated the need for capacitor banks and long-term reliability upgrades on the 115/46 kV system serving Tower, Ely, Winton, and Babbitt.

Duluth 34 kV



Evaluated the configuration of the existing 34.5 kV network within Duluth, looking at expanding the network to help offload the 13.8 kV system and provide full capacity ties to the 13.8 kV feeders. This study impacted the 15th Ave West Transformer Addition Project (2021-NE-N6) and the Ridgeview Transformer Addition Project (2023-NE-N9).




Evaluated load-serving needs in the Verndale area to identify long-term transmission and distribution solutions, particularly as they may impact the scope of the Verndale Substation Modernization Project (2021-NE-N4).

Onigum Area Study



Study the Onigum area for a possible 115 kV conversion.

3.3    Regional Studies

While every study undertaken adds to the knowledge of the transmission engineers and helps to determine the transmission facilities required to address long-term reliability and to transport renewable energy from various parts of the state to the customers, some studies are intentionally designed to take a broader look at overall transmission needs. Regional studies analyze the limitation of the regional transmission system and develop transmission alternatives to support multiple generation interconnection requests, regional load growth, and the elimination of transmission constraints that adversely affect utilities’ ability to deliver energy to the market in a cost-effective manner. 

MISO started a Regional Transmission Overlay Study (RTOS) in 2016, but due to limited benefits identified in the study MISO has put the study effort on hold.

3.3.1  MISO Transmission Expansion Plans

MISO engages in annual regional transmission planning and documents the results of its planning activities in the MTEP reports. The MTEP process is explained in detail in chapter 6 since the latest MTEP reports are being relied on to provide information about the transmission inadequacies identified in this Report. Earlier MTEP Reports were summarized in past Biennial Reports. For convenience, the following brief description of the latest MTEP reports is presented here. The MISO Expansion Plans are available on the MISO webpage. Visit http://www.misoenergy.org and click on “Planning.”

MTEP20 Report
The MTEP20 report identified projects required to maintain reliability for the ten-year period through the year 2029 and provides a preliminary evaluation of projects that may be required for economic benefit up to twenty years in the future.

According to the MTEP20 Executive Summary, the MISO staff recommended approval of approximately $2.5 billion in new transmission infrastructure investment. Of the $2.5 billion, $1 billion is new Baseline Reliability Projects, $606 million is Generation Interconnection Projects, and the remainder falls into the Other category.

MTEP21 Report
The MTEP21 report identified projects required to maintain reliability for the ten-year period through the year 2030 and provides a preliminary evaluation of projects that may be required for economic benefit up to twenty years in the future.

According to the MTEP21 Executive Summary, the report included 335 new transmission projects, equaling $3 billion in investment to address near-term reliability needs and aging infrastructure. Of the $3 billion, $345 million were Generator Interconnection Projects, $187 million were new Baseline Reliability Projects, and approximately $2.5 billion fell into the Other category.

MTEP22 Report
The MTEP22 report identified projects required to maintain reliability and provides a preliminary evaluation of projects that may be required for economic benefit up to twenty years in the future.

According to the MTEP22 Executive Summary, the report proposed approval of 382 new transmission projects with $4.3 billion in investment to address current reliability needs and regional upgrades. Of the $4.3 billion, $8 million were Market Participant Funded projects, $547 million were Generator Interconnection Projects, $545 million were new Baseline Reliability projects, and approximately $3.17 billion fell into the Other category.

The MTEP23 DRAFT report identifies projects required to maintain reliability and provides a preliminary evaluation of projects that may be required for economic benefit up to twenty years in the future. MISO updated the MTEP portal on October 17, 2023, which can be found at MTEP23 Report (misoenergy.org).

3.4   Load-Serving Studies

Load-serving studies focus on addressing load serving needs in a particular area or community.  Since many of the inadequacies in Chapter 6 are driven by load serving needs, many of these studies relate to specific Tracking Numbers.

Study Title

Anticipated completion

Utility lead for Study


South Washington Load Serving Study



Develop a comprehensive plan to serve the growing load around the City of Woodbury in eastern Twin Cities Area. 

Great River Energy Large Load Studies



Great River Energy has had multiple requests across its member systems’ service areas for potential large load installations. These loads have ranged from 2.5 MW to 500 MW. These requests have non-disclosure agreements and therefore are not communicated until the requesting party makes a decision to allow communication to other parties. Smaller load requests on occasion can be supplied by the existing transmission system, however in most cases new transmission will be required to serve these loads. Upon approval by the requesting party, Great River Energy will work with neighboring transmission owners in assessing the system for impacts for certain desired locations. Great River Energy will work with the State, if needed, upon notification of approval of a selected location for the new load.

Fergus Falls Area Study



The Fergus Falls area study is needed to evaluate the transmission system for any reliability violations (voltage or thermal), assess the capability the transmission system to serve a large load, and determine the best value plan that addresses system violations (if any) and reliably serves new and existing load in the Fergus Falls area.  

16 Minn. R. 7848.1300(F).

17 Minn. R. 7848.1300(B).