Refer to Table PR-22 Summary of Changes.

After completing the 2007 Update process late in the summer of 2007, ATC became aware of the potential for extremely low hydro output in the eastern portion of the upper peninsula of Michigan, particularly during times of winter peak loads. During the fall of 2007, ATC has been working with customers in this area to develop emergency plans to prevent overloads and extremely low voltages in this area if critical equipment were to fail to operate as needed. Some emergency projects ATC is developing, which we were not able to include in the 2007 Update project lists, include second transformers at the Straits and Hiawatha substations and advancing installation of capacitor banks at the Nine Mile Substation. ATC is continuing to work with our customers to explore longer term solutions that continue to provide reliable transmission service in this area.

Cancelled projects

Uprate M38 138/69-kV transformer

This project was cancelled due to the last study results. However, a more recent review of area load suggests a potential need may reappear in the near future.

Install 1-5.4 MVAR capacitor bank at Sawyer

This project was replaced with a distribution capacitor bank solution.

Deferred projects

Install 1-4.08 MVAR capacitor bank at L’Anse 69 kV

This 2008 proposed project has been deferred to 2009 as a result of revised construction schedules.

Relocate Cedar Substation (North Lake)

This 2008 proposed project has been deferred to 2009 as a result of revised construction schedules to support development of other critical projects.

Rebuild/convert Conover-Plains 69-kV line to 138 kV

Construct 138-kV bus and install a 138/69-kV, 60 MVA  transformer at Iron Grove Substation

Construct 138-kV bus and install a 138/69-kV, 60 MVA transformer at Aspen Substation

Relocate Iron River Substation (Iron Grove)

These 2009 proposed projects have been deferred to 2010 due to regulatory approval delays.

Install second 345/138-kV transformer at Plains Substation

This 2008 proposed project has been deferred to 2009 due to updated power flow modeling.

Rebuild/convert Blaney Park-Munising 69-kV line to 138 kV

Portions of the Blaney Park-Munising 69-kV line will need to be rebuilt due to poor physical condition. Reliability of service to customers served by this line is also a concern because this relatively long line is currently operated radially from Munising (open at Blaney Park). The condition and rating of the line prevents us from closing both ends at the same time. If this line is converted to 138 kV, it also could provide the continuation of another 138-kV outlet from the Presque Isle Power Plant in the Marquette area, enhancing the reliability of the substation.  This provisional project has been deferred from 2012 to at least 2013 to allow time to establish an appropriate long-term plan for the area that considers whether the line should be rebuilt at 138 kV or at 69 kV.

Other project changes

Install 1-4.08 MVAR capacitor bank at Roberts 69-kV Substation (2008)

ATC continues to assess reactive power requirements in an effort to optimize the size and location of the capacitor banks. Recently completed studies indicate that 1-4.08 MVAR capacitor bank will provide sufficient voltage support to the area, instead of the larger 5.4-MVAR size previously proposed.

Install 2-4.08 MVAR capacitor banks at Munising 69-kV Substation (2008)

ATC continues to assess reactive power requirements in an effort to optimize the size and location of the capacitor banks. Recently completed studies indicate that 2-4.08 MVAR capacitor banks will provide sufficient voltage support to the area, instead of the larger 2-5.4 MVAR banks previously proposed.

Uprate Chandler-Cornell 69-kV line clearance from 130 to 167 degrees F (2009)

This project’s status has been changed from provisional to proposed. The in-service date has been changed from 2010 to 2009 as a result of revised construction schedules.

Construct new Mackinac 138/69-kV Substation

Rebuild Hiawatha-Pine River 69-kV line ESE_6908

These two projects were previously proposed as a more comprehensive Eastern Upper Peninsula (U.P.) review, but have recently been changed to provisional status with yet to be determined in-service dates. Our ongoing review will assess if all or some of those projects should still be constructed in the future, constructed in a phased manner, or perhaps a different set of projects proposed. The results of this review and ATC’s future transmission plans in the Eastern U.P. will be communicated when the review is more fully developed.

New projects

Since the 2007 Update analysis was completed, two emergency projects have been proposed in the eastern Upper Peninsula. The following two additional projects have been recently added to our plans:

• Install second 138/69-kV transformer at Straits Substation
• Install second 138/69-kV transformer at Hiawatha Substation

As a result of the recent proposal of these projects, they do not yet appear in the tables or figures outlined in this Update. These two projects will be in-service by the end of 2007.

Construct ring bus at the Pine River 69-kV Substation and replace 1-5.4 MVAR capacitor bank with 2-4.08 MVAR banks (2008)

Install 2-16.32 MVAR capacitor banks at Perkins 138-kV Substation (2009)

Install 1-16.33 MVAR capacitor bank at Hiawatha 138-kV Substation (2009)

Install 2-4.08 MVAR capacitor banks at 9 Mile 69-kV Substation (2010)

Install 1-16.33 MVAR capacitor bank at Indian Lake 138-kV Substation (2010)

These proposed projects will boost the voltage in the Eastern Upper Peninsula under normal and single contingency conditions to acceptable levels until additional reinforcements can be implemented in the area.

Uprate Empire-Forsyth 138-kV line to 302 MVA (2008)

This planned project will boost the voltages in the Marquette County area under single contingency conditions to acceptable levels.

For a comprehensive list and graphical depiction of the projects in Zone 2 please refer to Table PR-14 and Figure PR-2.