On July 25, 2022, the Midcontinent Independent System Operator (MISO) Board of Directors announced that they had approved a portfolio of long-range transmission projects for the Midwest subregion.[1] The $10.3 billion investment includes 18 transmission projects. According to MISO, this Tranche 1 portfolio is the first of four planned tranches in its Long-Range Transmission Planning (LRTP) process. The grid operator plans to follow this portfolio with another set of transmission projects for its northern and central areas, one for its southern region, and one to increase transmission capacity between its northern and southern areas. The projects are necessary to begin the integration of new generation resources outlined in MISO member and state plans as well as increase resiliency in the face of severe weather events.

Analyses indicate that the Tranche 1 benefits will exceed costs, with a benefit-to-cost ratio of at least 2.2 for all resource zones in the grid operator's Midwest subregion. Benefits include congestion and fuel savings, avoided capital costs of local resource investment, avoided transmission investment, resource adequacy savings, avoided risk of load shed, and decarbonization. MISO used existing transmission corridors to plan this Tranche 1, which reduces the impact on local areas and communities, lowers construction costs, and shortens implementation time.

[1] https://www.misoenergy.org/about/media-center/miso-board-approves-$10.3-in-transmission-projects/