During the Polar Vortex 2019, otherwise known in North Dakota as a “cold snap”, it’s a great time to talk about three concepts: reliability, dispatchability and resilience. Reliability is related to the ability of a power source to be producing power when it’s needed. Dispatchability is the ability to move electricity to where it is needed, and resilience is the ability to respond to extreme situations favorably.
On January 29 – one of the coldest days this winter — only two major fuel sources were reliable, dispatchable and resilient: coal and nuclear. In the Plains region, supplied through MISO, coal was providing 49 percent of the electricity and operating at 73 percent of its installed capacity.
Lignite-based electricity was reliable, dispatchable and resilient. Even more so in North Dakota, where our power plants are right next to the coal mines, meaning there are no transportation bottlenecks. North Dakota’s power plants continuously provide thousands of megawatts of power to the grid. The region’s nuclear facilities likewise were providing 13 percent of the electric needs and using 85 percent of their capacity on January 29. Although all coal facilities are resilient, lignite and nuclear share the attribute of fuel security—neither relies upon pipelines or rail for their fuel supplies.
Now, when we look at natural gas, although gas plants were providing 25 percent of MISO’s electric needs, residential gas was suffering from a “dispatchability” problem. Thousands of Minnesota residents had been asked to turn down their thermostats and switch to more reliable and dispatchable electric space heaters to stay warm (and that electricity came from coal, gas, nuclear, wind, etc.) Factories in the Midwest were closed down because they couldn’t get natural gas to their facilities. So although in most circumstances gas is reliable, dispatchable and resilient, in late January it was behind coal when it came to resilience, and the ability to cope with such an extreme event.
Wind was providing 7 percent of the electricity in MISO on the bitterly cold day, and was operating at 34 percent of its capacity. Wind is never really a dispatchable resource, but the 7 percent that was feeding into the grid did help keep people warm, particularly as folks were relying upon electric space heaters due to gas constraints. Compounding the issue with wind is that it’s less dispatchable when temperatures fall into the teens (and more) below zero—meaning the wind might be blowing but the energy can’t be captured and dispatched to where it’s needed. As for resilience, a single wind farm is not resilient, since it’s completely at the mercy of local conditions. MISO has somewhat compensated for this by spreading wind farms over a wide geographic region, meaning whatever wind is being produced at any given time is fairly resilient, but since that is wholly dependent upon the weather, it’s hard to say it’s as resilient as coal or nuclear.
Jason Bohrer
President and CEO
Lignite Energy Council