Facing competition from renewables and cheap natural gas, coal-fired power plants are learning they must adjust to survive.
For decades, many coal plants burned coal as fast as their facilities could handle.
"The best way they operate is you turn them on, you run them up as high as you can, and you let them run for days," said Dale Niezwaag, vice president of government relations for Basin Electric Power Cooperative.
But this is changing, he told legislators Tuesday on the interim Energy Development and Transmission Committee. Lawmakers were beginning a study of wind energy and will also seek a separate, comprehensive study of all types of energy to be completed before the next legislative session convenes in 2019.
Niezwaag said Basin's coal plants are increasingly operating at a lesser capacity when the demand for their power is low, like when wind turbines are spinning on a windy day. They ramp back up when demand soars, like during a heat wave when everyone’s using air conditioning.
The problem, he said, is that Basin’s plants must maintain sufficient capacity to keep their emission controls working. And at low levels, they’re not profitable and face maintenance issues.
"When you start slowing them down, speeding them up, you start to get wear and tear on different component parts," he said.
Basin recently submitted comments on this to the U.S. Department of Energy, which is working on a study of the power grid. Niezwaag said the co-op would like power markets to pay more for coal-fired power as continue operating under this new kind of flexibility.