The Midcontinent ISO has selected developers for two critical transmission projects that will strengthen reliability and support the region’s long-term energy needs, it said on May 15.
The joint-developer partnership of Ameren Transmission Company of Illinois, GridLiance Heartland, LLC, Dairyland Power Cooperative, and the Illinois Municipal Electric Agency has been chosen to develop both the Woodford County – IL/IN State Line 765 kV Competitive Transmission Project (WIIL) and the Sub T – IA/IL State Line – Woodford County 765 kV Competitive Transmission Project (STIW).
These are the fourth and fifth of seven competitive projects identified in the Long Range Transmission Planning (LRTP) Tranche 2.1 portfolio approved by MISO’s board of directors in December 2024.
“The selection of this partnership delivers the best overall value for our customers, reflecting MISO’s commitment to enhancing the reliability and efficiency of the grid to ensure it can meet future resource developments,” said Aubrey Johnson, MISO’s Vice President of System Planning.
"These selections follow MISO’s rigorous competitive process that evaluates proposals based on cost and design, project implementation, operations and maintenance, and transmission planning participation – all relevant factors in ensuring project success," MISO said.
Together, WIIL and STIW will add more than 250 miles of new 765 kV high-voltage transmission lines and one new 765 kV substation to the grid, enabling large quantities of power to be transmitted efficiently across the Midwest.
“This partnership’s proposals stood out for both projects with its robust design offerings, well developed implementation plans, and sound cost containment features,” said Johnson.
The partnership will execute Selected Developer Agreements with MISO for both projects within 60 days. Construction activities will begin following regulatory approvals and permitting processes.
LRTP is a component of MISO’s Response to the Reliability Imperative -- the shared responsibility of MISO and its stakeholders to address the complex challenges to electric reliability in the region.
