ATC 10 Year Assessment – 2026

2026

10-Year
Assessment

Regional planning

ATC continues to participate in various planning efforts that address regional, inter-regional and Eastern Interconnection-wide needs that may affect our transmission system. ATC also continues to monitor the impact of changing energy policy, Federal Energy Regulatory Commission (FERC) and evolving regulatory rules. To help anticipate future demands on the electric grid, ATC conducts internal analyses and participates in regional studies. 

Regional Transmission Assessments

ATC is a member of two regional reliability organizations, the Midwest Reliability Organization (MRO) and the ReliabilityFirst Corporation (RF). ATC participates in regional transmission assessments conducted by the RF Transmission Performance Subcommittee (TPS). ATC also participates in the MISO’s Coordinated Seasonal Assessments (CSAs). 

MISO Planning Process

The MISO North region is divided into three sub-regions for planning purposes: West, Central, and East. The ATC footprint falls within the MISO West sub-region. ATC participates in a variety of MISO planning processes, including the MISO Transmission Expansion Plan (MTEP). The MTEP process evaluates transmission expansion for long-term, short-term, and targeted needs. 

Long-term studies are primarily value-based economic studies with a 10- to 20-year horizon. Transmission projects are proposed based on a projected future economic conditions. 

Short-term planning examines a 5- to 10-year horizon and is primarily driven by Transmission Owners’ reliability needs and compliance with NERC reliability standards. To date, projects that address short-term reliability needs have been proposed to MISO by individual Transmission Owners. Need drivers and alternatives are then evaluated through the MTEP process and studies. 

Targeted studies investigate specific issues in both the long- and short-term. Short-term, targeted, and long-term economic studies generally follow an approximately 18-month planning cycle. 

MISO Transmission Expansion Plan (MTEP) reliability and economic studies

ATC planning staff actively participates in the MTEP reliability and economic studies. These activities include: 

  • Ensuring ATC’s project information is accurate, comprehensive and complete when added to the MISO project database, 
  • Participating in the development and review of annual MTEP power flow and PROMOD models, 
  • Linking needs identified through MISO analyses to specific ATC projects, 
  • Reviewing and commenting on MTEP study results to support timely inclusion of ATC projects in MTEP Appendix A, 
  • Participating in the cross-border Regional Transmission Organization (RTO) studies, such as the Targeted Market Efficiency Project (TMEP), and other similar efforts, 
  • Ensuring appropriate cost allocation is identified for ATC projects eligible for regional cost sharing, 
  • Answering questions related to ATC projects at the West Subregional Planning Meetings (SPMs) and other stakeholder forums, and 
  • Providing suggestions and feedback to help improve the MTEP process

ATC projects are entered into the MTEP database to provide stakeholders with a more comprehensive and complete understanding of ATC’s capital plan. Projects are entered into the database based on expected initial capital cost. Projects included in ATC’s portion of the MTEP project list can also be found in ATC’s 10-Year Assessment. 

MISO Expedited Project Review (EPR) Process 

The Expedited Project Review Process is facilitated by MISO to study projects outside the regular MTEP cycle when an urgent system need could be jeopardized without an expedited system impact study. Projects submitted to the EPR process are presented at the EPR Technical Study Task Force (EPR-TSTF) meetings during the current MTEP cycle to receive stakeholder feedback and review. Projects are considered authorized to move forward to Appendix A after the Stakeholder Comment Period. For more information regarding MISO’s EPR Process, please refer to the MISO Business Practice Manual on Transmission Planning Section 4.1.4. 

Other MISO planning activities

Our planning staff participates in various technical and policy discussions that help inform MTEP activities. We also are involved in joint planning studies with neighboring RTOs, including PJM Interconnection (PJM) and Southwest Power Pool (SPP). MISO and PJM coordinate and conduct joint market efficiency project studies. These analyses are reviewed by an inter‑regional planning stakeholder advisory committee, which typically examines economic projects that could benefit both RTOs and qualify for cross‑border cost sharing. 

MISO Market Constraints

Two of the five narrowly constrained areas (NCAs) identified in the MISO region are associated with ATC. ATC tracks the NCAs to help identify projects that alleviate congestion within the MISO market.