Ameren energizes 96-mile transmission line in northeast Missouri

An Ameren subsidiary has energized a 96-mile northeast Missouri transmission line that was built to connect with other lines in Illinois and Indiana in order to move more renewable power westward across the Midcontinent Independent System Operator's footprint into Missouri.

Ameren Transmission Co. of Illinois (ATXI), a wholly owned subsidiary of Ameren Corp., said Monday it had completed and energized its 345-kV, $267 million Mark Twain Transmission project, which runs west from Palmyra to Kirksville, Missouri, then north to the Iowa border.

Work on the project, which included the Zachary substation in Adair County, Missouri, began on May 23, 2018.

"The speed and efficiency with which this line was developed and constructed can be attributed to the ongoing collaboration and strong communication efforts we had with landowners, community representatives and Northeast Missouri Electric Power Cooperative," said Shawn Schukar, chairman and president of ATXI.

Schukar said the project would help wind projects under development in Missouri that will provide lower cost energy to the grid, allowing the benefits of the project to far exceed the project costs.

Ameren Missouri, an Ameren power supply subsidiary, has entered into an agreement to acquire, after construction, a 400-MW wind farm in northeast Missouri, the largest to be built in the state.

The facility is being built by an affiliate of Terra-Gen in Adair and Schuyler counties in northeast Missouri and construction is expected to be completed by the third quarter of 2020.

MISO'S MULTI-VALUE PROJECTS

The Mark Twain Transmission Project was approved in 2011 by MISO. The project is part of a coordinated, multi-state group of transmission projects - known as Multi-Value Projects - being developed by transmission owners across the grid operator's footprint to improve and strengthen the regional energy grid.

In January 2018, the Missouri Public Service Commission granted ATXI a certificate of convenience and necessity for the project.

Other ATXI Multi-Value Projects include the Spoon River Project in Illinois, which was completed in February 2018, and the Illinois Rivers Project, with an anticipated in-service date of December 2020.

The Spoon River project is a 44-mile, 345-kV transmission line between Galesburg and Peoria, Illinois.

That $130 million project helps support the State of Illinois' Renewable Energy Portfolio Standard, which targets sourcing 25% of Illinois' energy generation from renewable facilities by 2025-2026.

ATXI is also building the 375-mile, $1.4 billion Illinois Rivers - a 345-kV line that will run between Palmyra, Missouri and Sugar Creek, Indiana.

That line will cross the Mississippi River at Quincy, Illinois. According to ATXI spokeswoman Lori Light, there remains just 30 miles of land clearing and line installation to be completed at the Sugar Creek end of the line.

-- Jeffrey Ryser, jeffrey.ryser@spglobal.com

-- Edited by Keiron Greenhalgh, newsdesk@spglobal.com