78 Degrees Isn’t Always the Optimal Thermostat Setting During a Heat Wave

Why 78 degrees isn't the right thermostat setting for everyone during a heat wave

Across the U.S., it's a hot summer, and electricity prices are high. Various public officials and corporate websites suggest people set their thermostats to 78°F (25.6°C), or even 81°F (27.2°C), as a way to stay relatively cool without breaking the bank. But as someone who studies energy costs, I know from both personal and professional experience that it's not that simple.

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Credit: The Spruce / Tessa CooperKey PointsAfter a heat wave, HVAC experts perform maintenance tasks like cleaning condenser coils and changing air filters.Experts caution against letting outside air and cranking your thermostat down after a heat wave.Clean the outdoor condenser coil with a garden hose and set a consistent, moderate thermostat temperature.After emerging from a scorching heat wave, it can be difficult to figure out how to best ke…

78 degrees isn’t always the optimal thermostat setting during a heat wave

It may be useful to start at 78 F (25.6 C) to keep a lid on costs, but that temperature is neither a safety threshold nor a temperature every household will find comfortable and safe

Why 78 degrees isn’t the right thermostat setting for everyone during a heat wave

Elbert Yazzie adjusts his air conditioning unit in Tuba City, Ariz., in 2025. Frederic J. Brown/AFP via Getty ImagesAcross the U.S., it’s a hot summer, and electricity prices are high. Various public officials and corporate websites suggest people set their thermostats to 78 degrees Fahrenheit (25.6 degrees Celsius), or even 81 F (27.2 C), as a way to stay relatively cool without breaking the bank. But as someone who studies energy costs, I know…

Why 78 degrees isn’t the right thermostat setting for everyone during a heat wave

by Destenie Nock, Carnegie Mellon University, [This article first appeared in The Conversation, republished with permission] Across the U.S., it’s a hot summer, and electricity prices are high. Various public officials and corporate websites suggest people set their thermostats to 78 degrees Fahrenheit (25.6 degrees Celsius), or even 81 F (27.2 C), as a way to stay relatively cool without breaking the bank. But as someone who studies energy cost…