What's the best temperature to set AC during a heat wave?

Eduardo Cuevas and Steve Howe
Updated ·3 min read
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As much of the U.S. copes with stifling heat this weekend, air conditioners have been humming, aiding comfort and survival.

But what's the best temperature setting during a heat wave? And what can you do to help keep your living space cool during the summer heat?

The Department of Energy recommends setting the temperature to what you find comfortable and provides humidity control, though highlights the fact that the smaller the difference between indoor and outdoor temperatures, the lower the overall cooling bill will be.

Other factors to consider include any health conditions of people in the household, how much you are willing to pay for your electric bill and what other cooling methods, such as a fan, you’re using.

The Environmental Protection Agency’s Energy Star program, which promotes energy efficiency, recommends setting air conditioners to 78 degrees for peak comfort and energy efficiency when you wake up.

But not a lot of people follow that recommendation.

Air conditioners will work hard during this week's Excessive Heat Watch spinning electric meters faster for higher bills. Power companies recommend increasing your thermostat to save.
Air conditioners will work hard during this week's Excessive Heat Watch spinning electric meters faster for higher bills. Power companies recommend increasing your thermostat to save.

A 2021 Consumer Reports survey found people with central air conditioning set it to a median temperature of 72 degrees, considerably cooler than the energy-saving recommendation. None of the survey respondents selected a temperature warmer than 76 degrees.

In general, Energy Star recommends setting the temperature 4 degrees warmer when sleeping and 7 degrees warmer when away from home.

A programmable thermostat can help regulate these temperatures, Energy Star says. And installing it further from areas that receive cool or heat, like an AC unit or window that takes in sunlight, can help.

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It can save you money to turn the temperature up while you're gone, but turning off the system would cost more money. If you'll be gone for a week or more, it would be worth it to turn it off.

For daily travel into the office or even a weekend away, it won't do much to help with bills.

Utility costs continue to be a concern for New Yorkers, especially as the summer hits.
Utility costs continue to be a concern for New Yorkers, especially as the summer hits.

There are other ways to keep your house cooler. Windows can cause significant unwanted heat that’s trapped inside, according to the Federal Emergency Management Agency. Here are a few steps to aid cooling:

  • Adding window curtains;

  • Limiting heat-producing appliances,

  • Checking weather stripping on doors and windows;

  • Installing ceiling fans to help circulate air, though don’t use this as a sole cooling device. FEMA warns this can give a false sense of comfort with air flow that doesn’t reduce body temperature or prevent heat-related illness.

EPA data suggests energy demand from air conditioning is on the rise. The number of warmer days has increased as the climate has warmed at the same time the number of cooler days has decreased.

Contributing: Jordan Green, Memphis Commercial Appeal; Greg Giesen, Delaware News Journal; and Manahil Ahmad, The Bergen Record.

This article originally appeared on USA TODAY: What's the best temperature setting for AC during the heat wave?