The Midcontinent Independent System Operator (MISO) announced that a consortium headed by Ameren Transmission Company of Illinois and NextEra Energy's GridLiance Heartland was selected to construct and operate two interstate transmission projects in the Midwest.
The consortium also comprises Dairyland Power Cooperative and the Illinois Municipal Electric Agency (IMEA). Collectively, the partners will deliver two state-line transmission projects intended to carry power to communities across the region.
Project details
- Sub T - Iowa/Illinois State Line - This project will add two new transmission lines totaling 149 miles, with an estimated capital cost of $940 million. One of the lines will extend westward from the Woodford County Substation to the Iowa/Illinois state line. The second line will continue west from the state line to the Sub T Substation located in Iowa.
- Woodford County - Illinois/Indiana State Line - This project includes two new transmission lines spanning 88 miles and the construction of a new substation, with an estimated cost of $718 million.
Ownership and financing
Ownership stakes in both projects will be allocated as follows: Ameren 43%, GridLiance 43%, Dairyland Power Cooperative 11%, and IMEA 3%.
Timeline and approvals
Both projects are currently expected to enter service in 2034. That timing assumes completion of regulatory reviews and the planned rounds of stakeholder and community engagement.
Context and next steps
The awards signal a multi-partner approach to regional transmission build-out, with clearly defined ownership shares across the participants. The projects will proceed through regulatory processes and public engagement before construction and commissioning can be finalized.
Note: The schedule and cost estimates described above are those provided at the time of the selection and remain subject to regulatory review and stakeholder input.