With its 2025 cycle of transmission projects not yet final and approved, MISO already is working through 43 expedited project requests ahead of its 2026 cycle to support almost 14 GW of new load.
Since June, MISO has fielded 43 expedited project requests for the 2026 MISO Transmission Expansion Plan (MTEP 26). Many of the project proposals deal with large load additions; together they represent 13.765 GW of new load.
At a Nov. 4 teleconference of the Expedited Project Review Technical Studies Task Force, Expansion Planning Manager Zheng Zhou said that over the past two years, large load interconnection projects have “increasingly utilized” MISO’s expedited review process for projects that cannot wait until end-of-the-year approval through the RTO’s annual MTEP process.
MISO fielded five project requests in June and approved two. Of the remaining three, two are under study and one was recommended for approval at the Nov. 4 meeting.
Of the 15 requests in August, MISO has approved five and recommended six more for approval Nov. 4, with four under study, including Entergy Louisiana’s Mount Olive-to-Cargas 500-kV line and substation work to support a new Meta data center in Richland Parish.
In October, MISO received 23 expedited requests and so far has recommended two for approval. Those two are smaller, age- and condition-based upgrades in Louisiana for 1803 Electric Cooperative, which joined MISO in June. MISO staff said 1803 is trying to get a jump on securing long-lead equipment for a “like-for-like replacement with no topological change.”
MISO has pivoted to a bimonthly processing approach to handle its growing number of transmission projects submitted by members for expedited treatment.
The grid operator now opens an acceptance window every other month for expedited project requests, with the next one in December. It has said the new cadence should be less cumbersome for staff than its previous ad-hoc approach. Until mid-2025, MISO evaluated requests as it received them. (See MISO Starting from Scratch on New Schedule for Reviewing Expedited Tx Projects.)
MISO studies smaller expedited projects in batches while larger, more complex projects receive individual assessments. It has a goal of a 30-day study turnaround for more straightforward projects. The RTO also schedules a single, monthly Technical Study Task Force meeting to discuss expedited projects instead of holding piecemeal, short task force meetings every time a request pops up.
MISO has experienced a runaway volume of expedited requests in recent years as load growth surges. The RTO said it used to process an average of six expedited requests annually before 2021. MTEP 25 contains 49 expedited transmission projects. The projects themselves are becoming larger and more complex.
MTEP 25’s more than $4 billion in expedited investment eclipses MTEP 24’s $896 million worth of expedited requests and MTEP 23’s $684 million. MISO said expedited projects are responsible for most of the 11.6 GW of large load additions that MTEP 25 will support.
Some stakeholders have asked MISO to consider adopting a load interconnection queue similar to its generator interconnection queue because of the snowballing expedited requests.
