UNDERWOOD, N.D. (AP) — An electric company will improve a transmission line that moves power from central North Dakota to a town outside Minneapolis.
Great River Energy is planning to spend $130 million on the CU HVDC line, whose name stands for high-voltage direct current. The line moves 73 percent of the cooperative’s power supply, taking nearly 450 miles from Underwood, North Dakota, to Buffalo, Minnesota, the Bismarck Tribune reported.
The work is needed to continue producing power at Coal Creek Station, largest coal-fired power plant in North Dakota, said project manager Greg Schutte.
“It’s an investment in the station and an investment in Coal Creek Energy Park,” Schutte said.
The company is making the improvements to two stacks on either end of the line. Those stacks convert power before it is moved.
“We had inklings the stations were getting too old,” Schutte said, so the utility performed a assessment of the system. “We found out we had some issues.”
The power plant and transmission system will be shut down for 74 days starting in March and run at half power for all but three days of total shut down. Contractors will use that time to gut and rebuild the two stacks.
“We’re basically just keeping a shell,” Schutte said. “That’s a huge outage for us.”
The system will see a 7-megawatt efficiency gain because it will be cooled by water rather than air. The utility now has to power fans that push air through the system.
Schutte said there are only five transmission lines like the CU HVDC line, which he said is one of the oldest still in service. The line provides power to about 500,000 customers in Minnesota and Wisconsin, and runs almost all the time, according to Schutte.