Grid operator MISO selects Ameren, NextEra unit to build transmission projects in Midwest

Ameren

19/05/2026 11:02

May 19 (Reuters) - Grid operator Midcontinent Independent System Operator (MISO) said on Tuesday it has selected a consortium led by subsidiaries of utility companies Ameren and NextEra to build and operate two transmission projects in the U.S. Midwest.

Ameren Transmission Company of Illinois and NextEra's GridLiance Heartland will lead the consortium, which also includes Dairyland Power Cooperative and Illinois Municipal Electric Agency.

MISO said it plans to build two state lines that will deliver safe, reliable and cost-competitive energy to Midwest communities.

The Sub T – Iowa/Illinois State Line (STIW) project includes two new transmission lines spanning 149 miles, and is expected to cost $940 million.

One of the lines will run from the Woodford County Substation west to the Iowa/Illinois state line, and the other will continue west from the state line to the Sub T Substation in Iowa.

The Woodford County – Illinois/Indiana State Line (WIIL) project also includes two new transmission lines spanning 88 miles and a new substation, with an estimated cost of $718 million, MISO said.

Ameren, GridLiance, Dairyland and IMEA will have ownership stakes in both projects of 43%, 43%, 11% and 3%, respectively.

Both projects have expected in-service dates of 2034, following the regulatory review process and thorough stakeholder and community engagement.

 (Reporting by Vallari Srivastava in Bengaluru; Editing by Vijay Kishore)

 ((Srivastava.Vallari@thomsonreuters.com;))