American Transmission Co. projects

Project website for a Wisconsin-based company that owns and operates the high-voltage electric transmission system that powers communities in portions of the Upper Midwest.

ATC completed and placed into service in March 2010 a 35-mile, 345-kilovolt transmission line primarily on an existing transmission corridor between the Paddock Substation in the town of Beloit and the Rockdale Substation in the town of Christiana.

Interstate connection benefits consumers

This project benefits electric consumers differently from other electric transmission projects that ATC has proposed in recent years, which largely have been in response to weaknesses on the system and related reliability issues. The primary purpose of this high-voltage transmission line to the south is to give local distribution utilities improved access to participate in the wholesale electricity market – to purchase lower-cost electricity when prices are low and sell into the market when prices are high. The economic benefit of increased access can be passed on to end-use consumers. This is the first access project approved within the MISO footprint. While this project is largely driven by economics, it also benefits electric consumers with a stronger, more stable electric system.

Wisconsin has only limited transmission line connections to other states compared to its neighboring states. This transmission congestion limits the ability of electric utilities to fully participate in the interstate electricity market.

ATC submitted a construction application to the PSC in the spring of 2007 outlining its proposal and seeking regulatory approval. The route the PSC approved was ATC’s designated preferred (recommended) route along an existing utility corridor where a 345-kilovolt line is located. A second route alternative along another utility corridor approximately two miles east of the approved route was rejected by the PSC.

Project at a Glance
Communities affected:Beloit, Janesville, Fulton, Milton, Albion and Christiana
Line length:Approximately 35 miles along existing right-of-way
Voltage:345,000 volts
Cost:Approximately $133 million
End points:Paddock Substation in the town of Beloit and Rockdale Substation in the town of Christiana
PSC Docket ID:137-CE-149 Visit the PSC website
Public open houses:March 2007
Submit application to Public Service Commission:May 2007
Receive PSC decision:May 2008
Begin construction:September 2008
In-service date:March 2010