Developers of the $2.5 billion North Plains Connector say the 385-mile new HVDC transmission line will represent the nation’s first connection between three regional US electric energy markets—the Midcontinent Independent System Operator, the Western Interconnection and the Southwest Power Pool.

The transmission line will be able to carry 3000MW of energy (from any generation source) between the middle of the country and three energy markets, easing congestion on the transmission system, increasing resiliency and reliability and enabling fast sharing of energy resources across a vast area with diverse weather patterns, said the companies.

Grid United started preliminary work on the project in the summer of 2021, looking at constraints such as biological, land use, existing infrastructure and archeological/cultural sites, according to documents it created for stakeholder meetings.

On January 30, Grid United announced that it would team up with ALLETE, an energy company headquartered in Duluth, Minnesota that owns electric utilities, Minnesota Power and Superior Water, Light and Power of Wisconsin, in addition to other portfolio companies.

ALLETE and Grid United have signed a memorandum of understanding to explore transmission opportunities, with plans to execute a North Plains Connector development agreement in the first half of the year. The project represents an approximately $2.5 billion investment in Montana and North Dakota and will be a long-term asset for those states.

Connecting the North Dakota and Montana grids will help mitigate the impact of extreme weather events and accommodate the growing demand for electricity. ALLETE expects to pursue at least 35% ownership and would oversee the line’s operation.

“Additional investment in transmission is critically important to achieve a clean-energy future and is a key part of our ‘Sustainability-in-Action’ growth strategy as our national footprint expands,” said ALLETE Chair, President and CEO Bethany Owen.

“This innovative project is an important step toward a resilient and reliable energy grid across a wide area of the country and ties into important transmission projects being developed in the Upper Midwest and the Western Interconnection.”

The North Plains Connector project is in the development phase, with Grid United engaging with landowners and stakeholders to determine the best route for the line.

The companies expect project permitting to start this year as they work toward an in-service date of 2029, pending regulatory approvals.