The U.S. is virtually addicted to air conditioning. We use more energy on it than all of Europe, which has twice the number of people, or China, which has over four times as many. In fact, we use more energy on air conditioning than the rest of the world combined.
See Breaking the A/C Habit for helpful info on ceiling fans & Naturally Cool to learn about passive cooling (both @ nrdc.org).
Living the air-conditioned life means we hardly experience summer anymore except when we go on vacation to other countries. Then, we encounter summertime customs like siesta and call them quaint.
In other developed nations, people continue to live in homes designed for passive cooling — with high ceilings, courtyards, working shutters and other traditional elements that protect them from the heat. In America, homes are more likely to be built for air conditioning and to lack natural cooling features. The same holds true for workplaces.
Also, we Americans have let go of the habits that make summer heat tolerable (siesta being one). It’s as if people starting thinking: Why suffer the inconvenience of closing the blinds or eating cold meals in summer if air conditioning can make it feel like spring?
I’ve known many folks (friends and family among them) who leave the air conditioning running all summer long, regardless of the weather. Offices and apartment buildings often do the same, as a matter of policy. That’s almost a definition of waste.
There are less costly and more sustainable ways to cope with summer heat. These include:
1) Keeping heat from entering the home by reflecting or blocking it with shades, shutters, louvers, awnings, trellises, window and roof coatings, insulation and/or trees.
2) Removing heat by using natural ventilation during the cooler time of day and closing the home up during the hot hours per #1.
3) Reducing heat-producing activities, such as using the oven, dryer and dishwasher’s heat cycle, and limiting them to the cool times of day.
4) Using circulating fans when #1-3 aren’t enough to keep you comfortable or, on extremely hot days, circulating fans combined with air conditioning. The fan magnifies the cooling effect of the A/C, enabling you to raise the temperature by 4 degrees or more and still feel just as cool. So you actually save energy by using both machines, provided you really do turn up the thermostat.
Keep in mind that humans naturally adapt to the customary weather in the place they live — as long as they stay out of the air conditioning long enough to do so. That’s why there is no national definition of a heat wave (what’s dangerously hot to residents of Omaha may not be so to Atlantans) — and why reducing your use of air conditioning will also help reduce your need for it.