Pleasant Prairie-Zion Energy Center Transmission Line Placed in Service

American Transmission Co. last week energized a newly constructed 345-kV electric transmission line that establishes another important high-voltage interstate connection between Wisconsin and Illinois. The approximately 5-mi line runs from the Pleasant Prairie Substation in Pleasant Prairie, Wis., to the Zion Energy Center Substation in Zion, Ill. The new line will improve operation of the electric system in southeastern Wisconsin and northeastern Illinois.

“The new power line relieves congestion on the existing interstate transmission system, and will provide savings to electric utilities and their customers by creating a reliable pathway to move electricity from the most efficient generators to energy markets,” said ATC Major Projects Planning Manager Tom Dagenais.  

The Midcontinent Independent System Operator designated the project as one of 17 Multi-Value Projects across the Midwest that deliver significant economic benefits. This is the first of three ATC projects designated by MISO as Multi-Value Projects to be placed into service. MISO recognized the economic benefits of large capacity regional transmission lines when it introduced a portfolio of 17 projects whose costs would be shared among utilities and their customers across the entire MISO service territory. MISO estimates that the average utility customer in the region will see $23 in annual benefits from lowered delivered energy costs for about $11 a year in investment.

ATC received approval in April 2012 from the Illinois Commerce Commission and May 2012 from the Public Service Commission of Wisconsin to build the transmission line, and construction on the project began late last year.