ALLETE, Inc. and North Plains Connector LLC this week signed development agreements for the North Plains Connector project, a new, approximately 400-mile high-voltage direct-current (HVDC) transmission line from central North Dakota to Colstrip, Montana. The agreements outline each company?s roles and responsibilities as development of the North Plains Connector accelerates. ALLETE and Grid United had previously signed a memorandum of understanding in January 2023 to explore development opportunities for the North Plains Connector.

The North Plains Connector will be the nation?s first HVDC transmission connection between three regional U.S. electric energy markets?the Midcontinent Independent System Operator, the Western Interconnection and the Southwest Power Pool. Open to all sources of electric generation, the project will create 3,000 megawatts of transfer capacity across all 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. The project represents an approximately $3.2 billion investment in Montana and North Dakota and will be a long-term energy infrastructure 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 up to 35% ownership and would oversee the line?s operation.