Because of changing market conditions, Great River Energy's 1,141-MW Coal Creek baseload coal-fired plant in McLean County, N.D., no longer is needed to operate at full load around the clock, so it has returned to its "cycling" roots.
When the plant began cranking out electrons in 1979 about 50 miles north of Bismarck, GRE, a Maple Grove, Minn.-based generation and transmission cooperative, did not have enough demand to support all of its output.
"It took a number of years to operate at full load," Lyndon Anderson, a spokesman for the co-op, said in an interview. "During those times, we would cycle up and down. We did that successfully for a lot of years."
Then, demand increased and Coal Creek was needed for baseload generation, pressed into service on an around-the-clock basis.
Now, with the advent of wind energy in the upper Midwest and low utility load growth since the 2008 national recession, Coal Creek is experiencing a back-to-the-future scenario.
As Anderson noted, pollution-free electricity produced by wind farms in the region "is a must-buy" in the Midcontinent Independent System Operator Inc. market. MISO is a regional grid operator based in Carmel, Ind.
Older coal plants like Coal Creek often are relegated to complementary status in MISO's new dispatch pecking order.
According to Anderson, GRE has made some minor operational changes to Coal Creek, essentially "fine tuning" the plant so it regained the ability to efficiently cycle up or down on virtually a minute's notice.
"We foresee we'll have to do more cycling," dropping the plant's output to as low as 300 MW on occasion, he said. "We would get our signals from the MISO market for what to do. Wind [output] changes all the time. Wind has impacted the markets."
As the largest power plant in North Dakota, Coal Creek, which burns lignite coal from North American Coal Corp.'s adjacent Falkirk surface mine, still can run flat out when needed. Its capacity factor was above 95% on Dec. 27 with the region buried under a foot of snow and temperatures well below zero.
GRE has no plans to retire Coal Creek, which remains a key player in the co-op's 2,800-MW generation fleet comprised of coal, natural gas and biomass resources.
The co-op is preparing to shutter its coal-fired 189-MW Stanton Station Mercer County, N.D., in the coming months, as the power station is unable to compete economically with lower-cost gas and renewables, particularly wind, in a virtual zero-load growth environment.
Bob Matyi is a reporter for S&P Global Platts, which, like S&P Global Market Intelligence, is owned by S&P Global Inc.