ATC scales back Bay Lake project by 230 miles

American Transmission Company (ATC) has scaled back the Bay Lake transmission project proposed last year as a collection of transmission lines and substations designed to enhance reliability in northeastern Wisconsin and the Upper Peninsula (U.P.) of Michigan.

The project was originally planned as 275 miles of 345-kV line intended to bolster the transmission system in the U.P. at a maximum cost of $895m, according to TransmissionHub data. Now, according to ATC, the revised project will extend 45 miles from Green Bay, Wis., into the U.P., at a cost estimated at $273m to $409m.

“Things are shifting and changing between transmission, generation, and electric load in the region of northeastern Wisconsin and the Upper Peninsula,” an ATC spokesperson told TransmissionHub Feb. 11. “We saw some real reliability needs there a year ago and they still exist.”

Essentially, northeastern Wisconsin and the U.P. are connected by one 345-kV line and a double-circuit 138-kV line. In May 2011, while the 345-kV line was out of service for maintenance, lightning struck the double-circuit 138-kV line, leaving the eastern two-thirds of the U.P. without power.

“If that lightning strike had hit a little bit closer to the Green Bay area, it had the potential to take a really wide swath of power out in northeastern Wisconsin, [resulting in] a much larger outage that would have taken a much longer time to restore power,” the spokesperson said.

In addition, ATC has a significant portion of load in the northern half of its service territory that runs constantly, making it difficult to take any components out of service for maintenance. 

“When you’re operating your system at the margins, you’re really putting reliability at risk,” the spokesperson said.

To remedy those issues, ATC originally proposed a 345-kV line from a new substation in the Green Bay, Wis., area to an expanded substation near Ishpeming, Mich., about 175 miles away; a 138-kV line from the new Green Bay area substation to the Morgan Substation near Oconto Falls, Wis., about 40 miles away; and two 138-kV lines between the Menominee County and the Escanaba, Mich., areas, about 60 miles apart.

However, at the end of 2012, the MISO board approved a 345-kV line from a new substation in the Green Bay area to the Morgan substation along with the proposed 138-kV line, as well as a single-circuit line from the Holmes substation in Menominee County.

Accordingly, ATC has deferred work on the 345-kV line from its Morgan substation to Marquette, the spokesperson said.

MISO planners declined to approve the bigger project because, as ATC noted, circumstances changed since the project was originally proposed.

Generation among the moving targets

One of the factors contributing to the change in project scope is the fate of the Presque Isle coal-fired power plant. At that time the project was proposed, We Energies raised the possibility of shutting the plant in Marquette, Mich., because the cost of installing pollution controls to comply with federal clean air rules would have made it uneconomic. However, in late 2012, We Energies and Wolverine Power Cooperative of Michigan announced a plan to install the necessary pollution controls. Wolverine would pay the $130m to $140m price tag in exchange for a minority interest in the plant.

The Presque Isle power plant consists of five coal-fueled units capable of generating approximately 344 MW. The units were built between 1974 and 1979, according to We Energies. With the plant’s continued operation, fewer power lines would be needed.

We Energies is a subsidiary of Wisconsin Energy Corporation (NYSE: WEC).