Minnesota Power and Great River Energy are set to build a 345kV high-voltage transmission line to strengthen electric reliability in northern and central Minnesota.

Great River Energy is a not-for-profit wholesale electric power cooperative that provides electricity through its 27 member-owner cooperatives and customers.

Minnesota Power provides electric service in northeastern Minnesota, supporting 150,000 customers, 14 municipalities and a few large-scale industrial customers in the US.

The two companies filed an application with the Minnesota Public Utilities Commission (MPUC), seeking a certificate of need and route permit for the Northland Reliability project.

Northland is a 180-mile (290km), double-circuit transmission line that primarily replaces the existing transmission corridors, from northern Minnesota to central Minnesota.

The construction of the transmission line project, which is estimated to cost around $970m to $1.3bn, is expected to begin in 2027, with plans to commence operations in 2030.

The Northland Reliability project is expected to support reliable electric service in northern and central Minnesota, along with the greater Upper Midwest region.

Great River Energy vice president and chief transmission officer Priti Patel said: “The pace of change is upon us and we are laser-focused on getting this line built to ensure reliability for our members and customers in northern and central Minnesota.

“We have gone to great lengths to engage with community members and critical leaders over the last year, understanding that no voice is more important than that of a cooperative member who will be hosting this project on their property.”

The Northland Reliability project is the first among the 18 transmission projects approved by the grid operator, Midcontinent Independent System Operator (MISO) in July last year.

MISO approved the project as the first phase of its ‘Long-Range Transmission Plan’ to integrate new generation resources and enhance grid resilience.

The Northland Reliability project is divided into two segments, the first segment includes laying 140 miles (225km) of new 345kV double-circuit transmission lines.

The new lines will be laid along existing transmission corridors, from Minnesota Power’s Iron Range Substation to Great River Energy’s Benton County Substation.

The second segment includes the construction of two 345-kV circuits, replacing a 20-mile (32km) 230kV line along existing transmission corridors from the Benton County Substation to a new Big Oaks Substation.

The project will also replace a 20-mile (32km) 345kV line along existing transmission corridors from the Benton County Substation to the Sherco Substation in Sherburne County.

Furthermore, the project includes other works, including the expansion of the Iron Range Substation and the Benton County Substation and the construction of a new Cuyuna Series Compensation Station in Crow Wing County.

Minnesota Power vice president of transmission and distribution Dan Gunderson said: “Collaboration with other utilities is critical as we invest in the transmission needed to maintain a reliable and resilient grid in northeast Minnesota and the Upper Midwest.

“Transmission is an integral part of Minnesota Power’s EnergyForward strategy for serving customers and communities as we work toward achieving both our vision and Minnesota’s energy policy goal of a carbon-free future.

“This project will help retain our outstanding reliability, provide system support as resources transition to different operating profiles, increase capacity, strengthen resiliency, and enhance grid flexibility.”