The torrid summers of the past few years have been among the hottest ever recorded on our planet. American households have responded to the heat by doubling our consumption of electricity for air-conditioning since the mid-1990s. Our A/C use has, in turn, boosted greenhouse gas emissions from power plants—helping to speed global climate change and to ensure that future heat waves will be even more frequent and intense … and that we’ll soon be cranking up the air-conditioning yet another notch.
But around the country, people are starting to recognize this vicious cycle and trying to put a stop to it.
I’ve met many people from across the country who enjoy the non-air-conditioned life, even in the heart of the Sunbelt. Here in Salina, Kansas, a place where triple-digit highs are common, my wife Priti and I have lived without air-conditioning for ten years.
Air-conditioning plays an important role in protecting the more vulnerable segments of our population during heat waves. But that doesn’t warrant its lavish deployment throughout society for much of the year. Whether you live in a house on a shady lot or in a third-floor urban apartment, it’s possible to stay comfortable by reviving and updating simple hot-weather strategies that have been cast aside during the age of air-conditioning. And it can be done without costly equipment or home renovations.
The key is to focus on people-cooling, not building-cooling. Your body is constantly converting chemical energy from food into heat; hot and/or humid weather makes it harder to unload that heat. But filling a home with chilled, still, dry air around the clock is only one of the many ways by which we can help our bodies maintain their thermal balance.
Keep air circulating. Air movement is highly effective in helping you evaporate perspiration and shed heat. On a merely warm day, a breeze through an open window is enough to do the job, but in truly hot weather, especially if it’s humid, turn on a fan. Ceiling fans are good, but the direct breeze from a portable or window fan can be more effective. In summer, we have a window fan blowing directly across our bed at night.
Don’t let the morning weather forecast scare you into reaching for the A/C switch. If all of the home’s occupants are away at work or school during the day, midday temperatures are not very relevant. If you are going to be home all day, the predicted high temperature or heat index may sound menacing; however, a naturally ventilated indoor space often remains at least ten degrees cooler than the outdoor maximum, and air movement knocks a few more degrees off the temperature your body is actually sensing. In a closed-up, air-conditioned home, a thermostat set in the mid-to-upper eighties would create a suffocating environment—but with open windows and moving air, living in such temperatures is no sweat.
Change your location with the time of day and sun position. If you’re fortunate enough to have a basement, take advantage of the geothermal cooling it provides. A fan enhances the effect. And if things get really tough, there’s no need to be an absolutist. For a few hours’ break, you can quickly and fairly efficiently cool down a one-room refuge with a window air-conditioner.
Reserve sedentary activities for the hottest part of the day. When physical work is called for, just accept that you may need to wring out your shirt afterward. Don’t do your running or other exercise at three in the afternoon under a broiling sun, but don’t do it in an air-conditioned health club either. Research shows that regular exertion in the heat builds the body’s tolerance, helping you function better in hot weather.
Don’t make extra heat. Remember that any energy-consuming household device releases waste heat. Plan meals that involve less cooking—cut back on boiling and baking especially. Keep the dishwasher and any unneeded lights turned off. Use solar technology—a clothesline—to dry the laundry. And take cold or lukewarm showers to avoid burdening your indoor atmosphere with a big load of humidity.
Get wet. High humidity may be the enemy, but water in liquid form is an essential ally. When it’s feasible, hit the lake or local swimming pool with your friends and neighbors. When it’s not (and if water supplies are sufficient), nothing cools like the old garden hose or lawn sprinkler.
Stay near plants. Head to the woods, where it always feels cooler. Plants can cool twice, by blocking sunlight and by absorbing heat as they transpire water. If you have a yard, you can further reduce the peak indoor temperature by creating more shade [pdf]. If possible, have trees, especially to the south and west. If that’s not possible, a dense stand of other kinds of tall plants—giant reed (Arundo donax) or sunflowers, for example—can be tall enough by July to shade the sun-baked sides of the house. We have grapevines covering a couple of windows.
Bring in the night air. If, when the sun starts going down, the outdoor temperature drops below that in the house, it’s a signal to pull in some of that outdoor air. Use a whole-house or attic fan if you have one; otherwise, set up one window fan blowing in and another out.
Meet your neighbors. Especially in the evening, spend time under a shade tree, patio umbrella, or screen porch, or head for the neighborhood park. Using natural cooling can help reverse the trend toward isolation from neighbors and nature that has characterized the age of air-conditioning.
The most important adjustment to be made is not in the thermostat but in our own view of what constitutes comfort. When people say they couldn’t survive without air conditioning, they tend to be thinking about the last time they dashed from a sun-baked parking lot into a chilled home or business. But focusing on those extremes ignores a wide range of perfectly livable, pleasant environments—that come at a much lower cost to you and the planet.