ALLETE and Grid United have formalised their partnership through development agreements for the North Plains Connector project in the US, a 400-mile (643km) HVDC transmission line between North Dakota and Montana.
The North Plains Connector project will carry 500kV and have a power transmission capacity of 3GW.
It will be the country’s first HVDC transmission connection between three regional US electric energy markets: the Midcontinent Independent System Operator, the Western Interconnection and the Southwest Power Pool.
Alternating current portions of the project will be connected to converter stations at the ends of the line where local grids have 345kV of capacity. The line will be open to all types of electric power generation and capable of transporting power in either direction.
The link will ease congestion, enhance system resiliency and reliability, facilitate the sharing of energy resources, mitigate the impact of extreme weather events and support increasing electricity demand.
It represents an investment of $3.2bn and will be a long-term energy infrastructure asset for North Dakota and Montana.
Allete and Grid United signed a memorandum of understanding in January 2023 to explore the project's development opportunities.
Allete plans to acquire a 35% ownership stake in the project and manage the line's operation.
Throughout 2023, Grid United has been actively engaging with landowners and regional stakeholders to refine the proposed route for the North Plains Connector.
The companies aim to work collaboratively on development activities. Land rights acquisition and regulatory filings will now begin and approvals are expected to be received in 2025, followed by construction. The targeted date of service is 2029.
Grid United CEO Michael Skelly stated: “We are excited to move the North Plains Connector forward with Allete, which brings considerable transmission expertise and experience to this important project.
“Connecting regional energy markets through new HVDC transmission lines is a critical need as more energy sources are brought online. This project will safeguard resilience and reliability across a wide area of the country by moving electricity from where it is generated to where it is needed.”