Minnesota Power, a division of ALLETE, has unveiled its plans to upgrade the high-voltage, direct-current (HVDC) transmission system that transports renewable wind energy from the Bison Wind Energy Center in North Dakota to customers in Minnesota.
To accomplish this, Minnesota Power intends to submit a Certificate of Need and Route Permit on June 1 to the Minnesota Public Utilities Commission. The purpose is to replace outdated critical infrastructure and modernize the terminal stations along the 465-mile HVDC transmission line spanning from Center, North Dakota, to Hermantown, Minnesota.
“Investing in transmission and replacing aging infrastructure with modern technology are critical to strengthening the reliability and resiliency of the grid in the Upper Midwest—especially as we experience more frequent extreme weather events and our energy supply continues to evolve,” said Julie Pierce, vice president Minnesota Power Strategy and Planning. “Maintaining and enhancing the reliable delivery of essential energy is a critical component of Minnesota Power’s EnergyForward strategy as we prepare to meet the state of Minnesota’s accelerated standard of delivering carbon-free energy by 2040.”
In Minnesota, the HVDC Modernization Project involves the replacement of aging converter facilities at the Arrowhead Substation in Hermantown with new structures and advanced electrical infrastructure near the existing terminal. Additionally, the project includes the construction of three short transmission lines, each less than a mile long, on the site to connect the new converter station to the existing electric system. Similar upgrades are planned for the converter facilities at the Square Butte East Substation in Center, North Dakota.
HVDC modernization project benefits include:
- Improves transmission system reliability.
- Minnesota Power seeks funding to minimize rate impacts, securing $15 million in state funding. Preferred supplier agreement with Siemens Energy ensures timely project delivery.
- Permits from North Dakota Public Service Commission will be sought for HVDC facility modifications.
- Enhances system resiliency with bi-directional line capability for flexible energy flow.
- Expands operating capacity for future energy transfers in the Upper Midwest.
- Replaces aging critical infrastructure.
- Pending regulatory approvals, construction could start in 2024 with completion expected between 2028 and 2030.
- Estimated project cost: $800 million to $900 million.
- Actively engages with landowners, stakeholders, and the public for feedback during the regulatory review process.