Midwest grid operator Midcontinent Independent System Operator (MISO) just approved the largest investment in transmission in U.S. history, beating its own prior record that was approved in July 2022. The planned transmission package, approved on December 12 and serving customers in the MISO North states (Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, Montana, North Dakota, South Dakota, and Wisconsin), will deliver huge financial benefits—up to a whopping $101 billion—and improved reliability while allowing as much as 100 gigawatts (GW) of new clean energy and batteries to connect to the grid.
MISO’s transmission infrastructure package includes three portfolios. The Tranche 2.1 portfolio will expand the region’s grid so that it can reliably move power across states as demand increases, driven by economic growth. This robust grid will offer flexibility and resilience during extreme weather emergencies and support the shift to clean energy resources, as planned by many states in the MISO North subregion.
The second group of transmission lines along MISO’s border with Southwest Power Pool (SPP), the Joint Targeted Interconnection Queue (JTIQ) portfolio, has been approved to enable around 28.6 GW of new generation resources located near this border area to connect to the grid more quickly and at lower cost. The U.S. Department of Energy recognized the unique and groundbreaking approach of the JTIQ study and its resulting portfolio with a grant that will reduce costs to new connecting generators by about a third. The third group consists of local projects identified by each transmission owner in the MISO territory that are needed to serve new loads and maintain reliability at the local level.
Long-range transmission planning is a must to ensure the grid is ready for the future
Robust transmission system planning is critical to improving reliability and ensuring customers have access to low-cost generation. MISO has consistently excelled in transmission planning—engaging a broad group of stakeholders and conducting transparent, detailed analysis of the region’s evolving energy needs to maximize regional benefits. The most recent approval continues MISO’s leadership role, one that provided an example to the Federal Energy Regulatory Commission when it required that all transmission providers engage in comprehensive long-range transmission planning. Other regional transmission organizations are already following MISO’s lead, with SPP just approving the largest transmission plan in its history and ISO New England kicking off a long-term transmission planning process in close collaboration with state partners. To MISO’s east, PJM is working to develop a long-range transmission planning process which, if successful, could help it ensure reliability during stressed grid conditions and reduce consumer costs.
This historic effort and plan are made possible by MISO staff and stakeholders’ consistent and diligent engagement with states and partners, as well as extensive work by MISO staff to analyze needs and develop transmission solutions with expansive regional support.
What’s next?
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Community input on transmission line routing: Before any of the Tranche 2.1 lines are built, there will be ample opportunity for community input. The utility in charge of each project will hold open houses where people can see graphics showing possible routes, voice their concerns, and make suggestions. The utility then considers this feedback and ultimately must get the approval of the state utilities commission. The whole process can take multiple years but may be less if the route uses an existing right-of-way.
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What about MISO South? This portfolio doesn’t address the South, right? There’s an urgent need for long-range transmission lines to help deliver reliability and lower-cost power to customers in the southern states of MISO: Arkansas, Louisiana, Mississippi, and Texas. MISO hasn’t extended its transmission planning effort to those states yet, and bill payers are losing out. Monopoly utility Entergy profits from the status quo, as inadequate regional transmission protects Entergy’s fossil generation from competition by lower-cost resources.
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More work ahead on the grid of the future: MISO has already indicated that additional transmission investment will be needed soon to address increasing load growth driven by data centers and other economic development. MISO’s commitment to ongoing, proactive planning will ensure that the Midwest has the most updated grid possible, supporting reliability for customers and utility plans for clean, low-cost energy resources.
