The Northwest’s blistering heat wave underscores the fragility of our grids

The record-breaking heat wave baking the Northwest US offers the latest example of how ill-prepared we are to deal with the deadly challenges of climate change.

The triple-digit temperatures in many areas have created soaring energy demands and strained the grid as residents crank up fans and air conditioners—in many cases newly acquired units in places that have rarely required them in the past. At least thousands of homes lost power around Portland, Seattle, and elsewhere in the last few days, creating potentially dangerous situations amid temperatures that can easily trigger heatstroke or worse.

Observers are worried there could be more widespread outages as temperatures climb higher this week and the heat wave reaches other regions.

Climate change is driving increasingly frequent, extreme, and extended heat waves around the globe, climate scientists consistently find. In this case, a high-pressure ridge parked along the Canadian border created what’s known as a heat dome, trapping hot air over an area stretching down to Northern California and as far east as Idaho.

California grid operators announced they’d likely call for voluntary reductions in electricity use on Monday. Shortfalls in supply are projected as temperatures threaten to reach the mid-100s in the inland part of the state.

While the main concern is the surge in demand that occurs as residents dial up air conditioning, heat itself can undermine the grid in other ways as well, says Arne Olson, senior partner at consulting firm Energy and Environmental Economics. Among other problems, it can reduce the efficiency of power plants, overheat transformers, and cause power lines to sag, in which case they may brush against trees and cause outages.

California faces the additional challenge of having less hydroelectric power available than normal amid extreme drought conditions. In addition, the operators of the West’s interconnected grids may not be able to count on much excess supply from other areas because the heat wave is affecting such a large swath of the country, Olson adds.

In many ways, what we’re witnessing is an electricity system largely built for the climate of the past increasingly struggle with the climate of the present, says Jane Long, a former associate director at Lawrence Livermore National Laboratory.

Bolstering our electricity systems for increasingly frequent or severe forms of extreme weather—whether this summer’s heat waves or last winter’s storms—will necessitate major upgrades of US grids, including moving to modern transmission and distribution systems, “weatherizing” generation sources like wind turbines or natural-gas plants, and adding far more energy storage.

It will also require a diverse array of power plants that can provide a steady supply in any weather scenario or time of day, Long says. That will become trickier to maintain as regions come to rely on ever larger shares of wind and solar power, which continually fluctuate. Studies by Long and others have found that states will need to incorporate additional carbon-free sources that can provide on-demand output, such as geothermal, nuclear, hydrogen or natural gas plants with systems that can capture climate emissions.

We’ll also need increasingly efficient and climate-friendly forms of air conditioning.

Soaring temperatures and severe drought conditions also increase fire risks, which call for additional changes in the electricity system, including burying lines, installing modern ones that shut off when a break is detected, and building distributed electricity generation and storage systems.

Power outages aren’t merely an inconvenience during heat waves: they can quickly become deadly as heat exhaustion turns into heatstroke, says Stacey Champion, a community advocate who has tracked indoor heat deaths in Arizona and pushed the local utility to suspend power shutoffs during high-temperature periods. “It’s known as the silent killer,” Champion says.

Indeed, heat waves kill more Americans than hurricanes, tornadoes, and earthquakes combined. Children, the elderly, and pregnant women are particularly vulnerable.

Studies find that the deaths and illnesses from soaring temperatures will only rise as climate change accelerates.