Staying Cool in Extreme Heat When the Power Fails

6 min read

July 7, 2023 -- Electrical grid failures, or blackouts, have significantly increased in frequency in recent years, placing millions of Americans at risk for health-related illness and death. This is especially true during the summer months, when extreme weather events (including heat waves, hurricanes, tornadoes, and wildfires) intersect to maximize demand for electricity. Over the past decade, failures have more than doubled nationwide, increasing a whopping 151% between 2015-2016 and 2020-2021, according to the U.S. Energy Information Administration. 

With record heat and smoke spreading across the country, this summer is already on tap to be one of the hottest, not to mention the most challenging for already fragile electrical grids. So what should people do when the power goes out, the air conditioning and fans go kaput, and the heat is relentless, aside from the usual tips such as staying hydrated or placing ice in front of a fan so that it blows cool air?

Mike Tipton, PhD, professor of human and applied physiology at the University of Portsmouth Extreme Environments Laboratory in Hampshire, U.K., has spent decades consulting with the military, industry, and elite athletes on strategies to maintain their “cool” in extreme environmental situations. But perhaps one of his most important lessons came from the least expected place: 1970s housewives.

“Many years ago – probably 50 or so – housewives used to say that when they got hot gardening or doing something outside, they would come in and run their hands under the cold tap,” Tipton explained. 

“So when we were looking for something for the Navy firefighters who have to go into very hot compartments wearing a lot of protective clothing, you start with how the body works. And we found that sticking their hands into cold water was as effective as anything else we could do for them.”

Before Things Get Out of Hand ...

Peripheral blood flow – how and where blood is transported through the body – is largely determined by deep body temperature. When it gets hot outside the body, the brain instructs blood vessels to divert blood flow to skin to aid in sweat and evaporation to ensure that the core or deep body temperature remains optimal. 

“The hands are very good heat exchangers because they have a high surface area to mass ratio,” said Tipton. “Hand immersion is a really good way of cooling the body.”

Hand immersion -- placing one’s hands in cold water for as little as 20 minutes -- is a great method of self-regulating body temperature and one that is easy to do so long as there is an accessible water supply. 

Short of sticking your hands in cold water, you could also hold a cold drink. Fortunately, both strategies are self-regulating. “When it starts to feel cold, you’ve probably done enough cooling,” he said.

Getting One’s Feet Wet

Who would have thought that one of the most common idioms in the English language -- getting one’s feet wet (meaning to become familiar with something) was actually a useful tool during extreme heat?

Colleen Scott, a Washington, DC, native, said that foot baths have long been her ‘go-to’ during the city’s relentless summers.

“I’m a big fan of a mini-shower where you wash your feet,” said Scott. “There’s something about getting my feet and ankles cold and all the circulation down there that helps you actually reduce your body temperature.”

Tipton noted that although the hands are better, the feet can also help the body cool its core, but he cautioned that for all of these approaches, water temperature is important. Avoid ice baths and ice soaks and opt for cold instead. 

“It’s the same with a shower,” he said. “Taking a shower to cool off before you go to bed is a good idea. But the shower shouldn't be freezing cold; a tepid shower is much more effective at removing heat from the body.”

Bare It All

When the temps are unbearable, clothing can become, well, equally unbearable. In fact, clothing can actually impair the body’s attempts at evaporation and cooling. 

“Clothing acts as a barrier for loss of heat from exercise,” said Tipton, referring to soldiers as a prime example.

“When you [think] about the military, they’re wearing protective clothing and carrying additional load, which increases their metabolic rate and their heat production, as well as impeding it. In that situation, you can get to the circumstances of various heat illnesses very quickly, [some which are] a medical emergency.”

Sara Andrabi, MD, an assistant professor of emergency medicine at Baylor College of Medicine and assistant medical director at Ben Taub Hospital Emergency Center in Houston, has also seen her share of heat-related illnesses and offered a few general tips.

“You want some air circulation,” she said, “so I always tell people to remove tight clothing or any heavy clothing they have on, and then apply cool compresses to their skin.”

This advice goes for athletic wear, which, Andrabi noted, interferes with sweating and cooling the body. 

“Wear loose cotton clothing,” she said.

Or if the circumstances allow, take it all off and sit around in your birthday suit.

Chill Out

Many people don’t realize that even simple tasks, like cooking meals without proper ventilation, can increase the amount of energy that the body expends.

“There are certain situations you don’t think can overheat you, and they’re not the typical things people think about,” explained Andrabi. But “more passive activities can certainly predispose you to heat-related illness.”

When it is hot as Hades and the electricity is not flowing, rest becomes increasingly important. This is a key reason why many people who live in Mediterranean countries take a siesta midday, when the sun is at its highest and hottest.  

Tipton advised that it’s also important to try to create natural convection, or air movement. 

“If you want to maintain an indoor environment that’s comfortable, you’ve got to try to stop heat getting into the house,” he said. “Make sure that you have as much air movement as possible, particularly early in the morning when the air temperature is relatively low. Open certain windows, wedge open doors to create a draft.”

Once it gets too hot, however, all bets are off. 

Tipton also echoed Andrabi’s point about meal preparation, but in the context of having working electricity and no means of cooling. In these cases, people might opt for simple, uncooked light meals rather than lighting the stove, which can generate a lot of heat. 

Fans vs. Fanning

Did you know that handheld fans were originally used in Asia over 2,000 years ago to deflect heat and bugs?

Over time, they were adopted by Victorian fashionistas as fashion accessories. Today, you might catch a menopausal woman whipping out a fan during a hot flash. But fanner beware! Fanning might not achieve the ultimate goal to reduce your core body temperature. 

“The most powerful thing in terms of blowing air over your body is not the temperature of the air; it’s the fact that it is enhancing evaporation,” explained Tipton. “If you give someone a fan, they [likely] fan their faces – we’ve got a lot of receptors on our faces. But [while] they’ll feel an awful lot more comfortable, they aren’t actually doing much in terms of deep body temperature."