Economic planning

ATC utilizes two methods to determine which projects have the potential for economic benefits:

  1. Stakeholder Input and Analyses
  2. Reliability Project Screening

These methods are described below.

Stakeholder Input and Analyses

In March 2008, Federal Energy Regulatory Commission (FERC) Order 890-A took effect. Order 890-A requires a coordinated, open, and transparent transmission planning process on both a local and regional level. To comply with these requirements, ATC submitted a compliance filing on Order 890-A that provides a timeline of actions to ensure that the economic planning process is both coordinated and open.  ATC has also submitted a compliance filing on Order 1000 that incorporates public policy requirement needs into its economic planning analysis.

Annually, ATC will use a process with consistent timelines that combines stakeholder input, historical data, future line flow forecasts, and updated information on the electric system to identify transmission upgrades for economic evaluation.

Each year:

  • During February, we hold an initial stakeholder meeting to review the market congestion summary and potential fixes and to discuss economic study scenarios, drivers, ranges, and assumptions.
  • By March 1, we work with stakeholders to request and prioritize new/other economic studies and recommend study assumptions.
  • By April 15 – we identify preliminary areas of economic study, study assumptions, and models and solicit further comments from stakeholders, including soliciting stakeholders for public policy requirements that drive transmission needs.
  • By May 15 – we finalize areas of economic study, study assumptions, and models to be used in analysis, including a determination as to why or why not public policy requirements were included in the assumptions.
  • By November 15 – we provide a summary of the results of the economic analyses to our stakeholders.

ATC conducts analyses of the projects identified for study over several months’ time and posts the key results, including the extent to which these savings offset project costs. When the expected benefits of a studied project are high enough to justify its costs, the process of developing it as a formal proposal is begun.

As a result of the 2020 ATC/stakeholder collaborative process, we are performing economic analyses on the following ATC facilities:

Economic Planning Study Areas
  • Darlington – North Monroe 138-kV Area
  • Concord – Crawfish River 138-kV Area

Studies are performed and results shared with stakeholders over the course of the year. In addition, customers and stakeholders who would like to request specific economic studies can do so if they are willing to pay for the studies and are willing to have the results posted publicly.

Reliability Project Screening

Economic analyses were performed on 16 projects from the 2019 10-Year Assessment project list to determine whether those projects were candidates for acceleration or deferral based on economic considerations. Please refer Table EP-1 for the list of projects screened. The list of 16 projects was based primarily on the availability of redispatch and capital costs of the projects; however, lower cost projects specifically identified by the ATC planning department were also included in the study. Generation interconnection and distribution interconnection projects were not eligible for inclusion in this list. Further, capacitor bank projects were not considered since the voltage benefits provided were not captured by the PROMOD software analysis. Finally, projects with in-service dates prior to 2023 were not considered since development of those projects was too far underway to make scheduling changes. As a result of this screening, none of the projects showed significant economic savings to ATC customers. This may change depending on assumptions or modeling of the system. Economic planning will continue to work with reliability planning, if any further analysis needs to be completed.

A similar analysis will be performed in the 2021 10-Year Assessment based upon the 2020 Assessment project list.

Table EP-1

Project #ProjectPlanning Zone
1Chaffee Creek SS - Lincoln Pump Station 69 kV (Y-18), Rebuild1
2Wautoma - Chaffee Creek 69 kV (Y-49), Rebuild1
3McKenna - Castle Rock 69 kV (Y-47)1
4Lincoln Pump Station - McKenna 69 kV (Y-145), Rebuild1
5Winona - Atlantic 69 kV (Winona69), Rebuild2
6West Middleton SS - Stagecoach SS 69 kV (6927), Partial Rebuild3
7Acadamy - Columbus 69 kV (Y-21), Rebuild3
8Portage SS - Columbia SS 138 kV (X-13/X-20), Rebuild existing double circuit3
9Darlington - Rock Branch 69 kV (Y-109), Rebuild3
10Gran Grae SS, Install a second 161/69 kV transformer3
11Hillman - Darlington 138 kV (X-14/X-101), Rebuild3
12South Fond du Lac - Spring Brook 69 kV (Y-133), Rebuild3
13Finger Road SW STA - Wesmark 69 kV (FIRY11), Rebuild4
14Wesmark - Rapids 69 kV (R-44), Rebuild4
15Oak St - Hwy V 69 kV (Z-26), Rebuild4
16Summit - Cooney 138 kV (6431), Rebuild5
List of 10-Year Assessment 2019 Economically Screened Projects

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