Power outagesPower Outages across the Plains: 4 Questions Answered about Weather-Driven Blackouts

By Michael E. Webber

Published 17 February 2021

Amid record cold temperatures and skyrocketing energy demand, utilities across the central U.S. have ordered rolling blackouts to ration electricity, leaving millions of people without power. Weather-related power outages are increasing across the U.S. as climate change produces more extreme storms and temperature swings. States that design their buildings and infrastructure for hot weather may need to plan for more big chills, and cold-weather states can expect more heat waves. As conditions in Texas show, there’s no time to waste in getting more weather-ready.

1. The Plains States Have a Lot of Wild Weather. Why Is This Cold Wave Such a Problem for Utilities?
The central U.S. has freezes, heat waves, windstorms, droughts and floods. All of these events stress the electric grid, pipeline networks, roads, rail and waterways. Right now in my state of Texas, ERCOT, a nonprofit corporation that manages the power grid for most of the state, is imposing rolling blackouts because demand for electric heating is very high. So is the Southwest Power Pool, which serves customers in 14 states from North Dakota to Oklahoma.

About 60% of homes in Texas have electric heat, and most of the rest use natural gas or propane. Normally our peak electric demand is on summer afternoons for air conditioning. But in this sustained cold, electric demand is spiking to keep homes comfortable and pipes from freezing. This storm is more extreme than the most severe winter conditions that ERCOT typically plans for.

At this time of year, power plants that run on coal or natural gas often shut down for planned maintenance ahead of the summer cooling season. That means we have less capacity available than usual right now.

To meet the difference between high demand and low capacity, utilities are cycling power on and off to different neighborhoods or regions of Texas in a methodical way to keep things in balance. If they didn’t do this, there would be a risk of a much wider-scale blackout, which would be catastrophic and life-threatening.

2. How Do Utilities Plan for This Kind of Extreme Weather?
Utilities everywhere follow the weather very closely. Temperature changes affect the need for heating and cooling, which drives demand for electricity and natural gas. Meteorological conditions affect the availability of wind and solar power.

Thermal power plants – which burn coal, natural gas or biomass – also need a lot of water for cooling to run efficiently, as do nuclear power plants. If climate change warms rivers or reduces their water levels, it could force those power plants to turn off or reduce their output.

Weather forecasting has improved as satellites become more abundant and computer models become more sophisticated. Utilities can take steps in advance of a major storm, such as asking customers to preheat their homes. For ratepayers who will do this, the utility may adjust their thermostats to reduce power flow when demand is high.