Turning Thermostats Down Keeps the Heat on During Polar Vortex 2019

The final week of January brought sub-zero temperatures to three-quarters of the continental US and much of Canada as a polar vortex bore down. Polar vortexes gained fame during 2014, when record-breaking low temperatures strained electricity grids across the US as residents tried to stay warm. During the 2019 polar vortex, natural gas and electricity demand were straining grid resources again. Residents of Michigan and Minnesota were called upon to turn down their thermostats and reduce use of electricity-intensive appliances.

Behavioral Demand Response

Demand response (DR) in the US has been in practice for decades. Utilities and other grid operators will call on residents to willingly reduce their electricity consumption during periods of high demand to increase grid reliability. In recent years, DR has made its way into natural gas as the fuel has become a leading source for generation. Amid widespread outages during the 2014 polar vortex, grid operators PJM Interconnection, New York Independent System Operator (NYISO), and Electric Reliability Council of Texas (ERCOT) used DR to help stabilize the grid. While the grid operators did not call a formal DR event during the 2019 vortex, Midwest utilities alerted their customers to the grid strain and asked them to chip in.

Behavioral DR relies on customers to voluntarily reduce their electricity and natural gas demand in response to notifications from utilities or to other incentives, such as price. Where some utilities have formal winter DR events, Detroit Edison (DTE), Consumers Energy, and Xcel Energy in Minnesota do not run formal winter DR programs. During the polar vortex, however, the companies were reliant on customers to cut down on electricity and natural gas consumption following formal requests from the utilities themselves and from Michigan’s Governor Whitmer.

Consumers Energy called on customers to reduce demand in part due to a natural gas shortage sparked by a fire that reportedly had nothing to do with the vortex. DTE and Xcel Energy, however, made the call strictly due to demand spikes caused by the freezing temperatures. In Michigan, customers were asked to dial their thermostats back to 65 degrees or lower. While DTE reports its infrastructure was operating sufficiently, the company noted that its system was connected to strained grids in other states and Canada. Xcel Energy faced more extreme conditions and consequently sought greater behavior change, asking residents in the Twin Cities to dial down to 55 degrees and customers in other parts of the state to reduce home temperatures to 60 degrees. Along with engaging residential behavior changes, Xcel Energy also worked with customers to pause industrial processes in some areas to provide grid relief.

The Dawn of Winter DR

Consumers Energy, DTE, and Xcel Energy operate year-round or summer DR programs aimed to reduce demand primarily when temperatures are high, but winter DR is not unheard of. The Independent System Operator of New England instituted a winter DR program even before the 2014 polar vortex, and some utilities in states like Florida use formal DR programs to manage their winter electricity peaks.

While research linking polar vortexes to climate change is nascent, many scientists believe that the coming years will bring more extreme temperatures to populated northern cities. As both electricity and natural gas DR programs provide more reliable load shifting and curtailment, utilities in the Northern US and Canada might increasingly pilot and scale winter DR programs to help keep the lights (and heat) on during colder months.