Unique features make our system reliable and efficient

It takes more than 100 substations, 4,800 miles of transmission lines including a unique HVDC transmission line, and strategically located technicians to meet the daily needs of our 28 member cooperatives.

Our HVDC line is unique

Although nearly all transmission lines transport alternating current (AC) electricity (the same type of current that goes into your home) Great River Energy’s transmission system includes a 400-kV high-voltage direct-current (HVDC) transmission line, which transports electricity from Great River Energy’s largest generation facility, Coal Creek Station in Underwood, N.D., to Minn. Great River Energy’s HVDC line was developed when designers determined it would be more efficient and reliable to transmit energy across North Dakota over an HVDC transmission line versus over an AC transmission line, and then convert it to AC for transmission within Minnesota.

The HVDC line:

  • Is 436 miles long
  • Contains more than 1,600 lattice steel towers
  • Operates at 400 kilovolts
  • Was energized in 1978
  • Outstanding reliability record
  • Ends at the Dickinson Converter Station in Buffalo, Minn.
  • Upgrade to advanced technologies was completed in 2019

View our HVDC fact sheet

The Dickinson Converter Station is part of the HVDC system

This is where Great River Energy’s HVDC line ends and the power that has been carried across North Dakota is converted back to AC power for transmission within Minnesota.

Power lines and substations are the work horses of the system

Great River Energy currently owns and maintains approximately 4,600 miles of transmission line, including the very high-voltage HVDC line mentioned above. Monitoring this vast system of power lines is one of the most important jobs we have. We also own, or partially own, more than 100 transmission substations, which we continuously update and enhance, often as part of power line projects.

Control centers are the brains of the system

Operators in the Great River Energy control center in Elk River, Minn., remotely control the transmission system using a highly reliable communications network. The control center performs critical functions needed to ensure smooth daily operations and facilitate responses during storms and heavy load situations. Our operators are in continuous contact with operators at power plants, converter stations and other utilities throughout the region. Through coordinated efforts, our operators make sure energy reaches all members and that the transmission system works as effectively as possible.

Strategically located staff and materials

Technicians, equipment and maintenance materials are strategically located at service centers throughout the Great River Energy service territory to help ensure reliable, responsive service to our members. Strategic locations allow technicians to respond swiftly to outages, and continually monitor and enhance the system.

MISO membership

Great River Energy is a member of MISO, an independent, nonprofit organization that supports the constant availability of electricity in 15 U.S. states and Manitoba, Canada. MISO oversees more than 71,000 miles of interconnected power lines and ensures the reliable transmission of more than 175,000 megawatts of energy in the Midwest, including Great River Energy’s 28 member-owner cooperatives. MISO also administers one of the world’s largest energy markets, which Great River Energy can access to provide the most economical and reliable energy to our members.

Visit MISO

Standards of conduct for transmission providers

The Federal Energy Regulatory Commission establishes standards of conduct for transmission providers.

View Great River Energy’s required information

Connecting to our system: what developers need to know

If you are a large or small power producer and would like to connect to Great River Energy’s transmission system, you are required to follow our interconnection guidelines.

View our interconnection guidelines