Long Range Transmission Plan

The Midcontinent Independent System Operator (MISO), in shared responsibility with utilities and states, through the Reliability Imperative, is leading the Long Range Transmission Planning (LRTP).  The focus of the LRTP, per MISO’s website is “to improve the ability to move electricity across the MISO region from where it is generated to where it is needed – reliably and at the lowest possible cost.”

The LRTP efforts have been broken into four tranches; the first of four tranches studied was unanimously approved by the MISO Board of Directors in July 2022.  The estimated cost of LRTP Tranche 1 Portfolio is $10.3 billion with a focus on transmission solutions that provide reliable and economic energy delivery for a reliable energy future.

ATC has actively participated in and provided resources and input into the LRTP process and is continuing to do so as studies for additional tranches continue.

LRTP Tranche 1 Portfolio*

There are 18 projects as part of LTRP Tranche 1 Portfolio; of these 18 projects, ATC has an ownership share in 3. These projects include:

MISO Project #Project NameMISO Project DescriptionIn-Service DateTotal Cost Estimate
4Wilmarth - North Rochester - TremvalInstall single circuit 345kV transmission line from the existing Wilmarth substation, to the existing North Rochester substation, to the existing Tremval substation.June 2028$689,140,000
5Tremval - Eau Claire - Jump RiverInstall single circuit 345kV transmission line from the existing Tremval substation, to the existing Eau Claire substation, to the existing Jump River substation.June 2028$504,500,000
6Tremval - Rocky Run - ColumbiaInstall single circuit 345kV transmission line from the existing Tremval substation, to the existing Rocky Run substation, to the existing Columbia substation.June 2029$1,049,500,000

The most current information on the Long Range Transmission Plan can be found on MISO’s Long Range Transmission Planning Page.

* Image source: https://cdn.misoenergy.org/20220527%20PAC%20Item%2002a%20MTEP21%20LRTP%20Report%20and%20Feedback%20Review%20Presentation624799.pdf