ITC invested $510 million to build this 345 kV line, which now serves as the backbone of a system designed to meet the wind energy potential of Michigan’s Thumb region.
ITC Michigan, through its ITCTransmission subsidiary, completed the Thumb Loop high-voltage transmission project in May 2015. ITC invested $510 million to build the 345,000 volt (345 kV) line, which now serves as the backbone of a system designed to meet the identified maximum wind energy potential of Michigan’s Thumb region. It also is contributing to regional system reliability and facilitating wholesale market competition.
The Thumb Loop Project consists of approximately 140 miles of double-circuit 345,000 volt (345 kV) lines and four new substations that serve as the “backbone” of the system. Additional lines and facilities will be needed in the future as wind generators go into service and connect to the backbone system to fulfill the requirements of the state’s Renewable Portfolio Standard.
The system is designed to meet the identified minimum and maximum wind energy potential of the Thumb region (2,367 and 4,236 MW, respectively) and is capable of supporting a maximum capacity of about 5,000 MW.
The new system was constructed in stages. The first segment, the western side of the loop from the Bauer substation in Tuscola County to the Rapson substation Huron County, went into service in September 2013. Phase Two, in St. Clair County, from the Fitz substation to Greenwood, went into service in May 2014. Phase Three, comprising 56 miles of line in Huron and Sanilac counties and the Banner substation near Sandusky, went into service in May 2015.