Every summer the same recommendation goes viral: set your thermostat to 78 degrees. It shows up in utility emails, news articles, and social media posts citing ENERGY STAR and the Department of Energy.
Here's the honest picture: the 78 degree number is real, but where it actually comes from is more complicated than most of those posts let on. And for Utah County homeowners trying to manage energy bills during triple-digit summers, understanding the real guidance is more useful than repeating a number.
Where the 78 Degree Number Actually Comes From
Per a Palm Beach Post investigation cited by Yahoo News, the 78 degree recommendation has been repeated so widely that most people assume it comes directly from ENERGY STAR or the Department of Energy as an official standard. It doesn't — at least not in the way most posts frame it.
The EPA clarified directly: "ENERGY STAR does not assert that any particular temperature setting is good for households." The 78 degree figure came through an older ENERGY STAR report that used it as an example setting in a programmable thermostat schedule. It was an illustration, not a prescription. Air conditioning companies, utilities, and news outlets repeated it until it became accepted as official guidance.
Per the actual Department of Energy's guidance on programmable thermostats, the DOE's real recommendation is simpler: "Set your thermostat as high as comfortably possible in the summer. The smaller the difference between the indoor and outdoor temperatures, the lower your overall cooling bill will be."
That's it. There's no magic number. The principle is: every degree you raise the thermostat reduces how hard your AC works and how much you pay.
The Numbers That Actually Matter
Per American Standard Air's HVAC analysis and Trane's 2026 thermostat guide, here's what the data actually supports:
Every degree above 72°F saves you up to 3% on cooling costs. Moving from 72 to 78 degrees is potentially 18% savings on your cooling bill. In a Utah County summer where AC runs hard from June through September, that adds up fast.
7 to 10 degrees warmer when you're away can save up to 10% annually on combined heating and cooling costs, per the Department of Energy. If you leave the house at 8am and come home at 6pm, running your AC at 85 rather than 78 during those hours is significant savings over a full summer.
4 degrees warmer when you sleep is the ENERGY STAR programmable thermostat example — so 82 degrees overnight if your daytime setting is 78. Most people actually sleep fine at slightly warmer temperatures than they expect, especially with a ceiling fan running.
Don't set it above 80 to 85 when away. Per Trane's 2026 analysis, your system needs to run often enough to remove humidity. In Utah County's dry climate this is less of a concern than in humid markets, but it's worth knowing — a system that never runs during a hot day can allow humidity to build in enclosed spaces.
What This Means for Utah County Homes Specifically
Utah County summers are dry and hot — not humid. That changes the calculation slightly compared to coastal or southeastern markets.
The DOE's principle of keeping the difference between indoor and outdoor temperatures as small as comfortable is the right frame. On a 105-degree Eagle Mountain afternoon, keeping your home at 78 means your AC is fighting a 27-degree differential. At 82 degrees, it's fighting a 23-degree differential. That's a meaningful difference in how hard your system works and how much it costs.
For newer Eagle Mountain and Saratoga Springs construction: Many homes built in the last five years have better insulation, higher-efficiency windows, and tighter building envelopes than older resale homes. These homes hold temperature better and your AC doesn't have to work as hard to maintain a given setting. If you're in a newer build, you may find 78 degrees is easier to achieve and maintain than you'd expect.
For older resale homes: Air sealing, attic insulation depth, and window efficiency matter significantly. A poorly insulated home fighting a 105-degree Utah County afternoon is a different situation than a new build. Before adjusting your thermostat expectations, it's worth knowing what your home's insulation situation actually is.
The Smart Thermostat Advantage
The best implementation of any thermostat strategy is a programmable smart thermostat that does it automatically.
Per American Standard Air, homeowners can save approximately $180 per year with a properly programmed smart thermostat. The Nest, Ecobee, and Amazon Smart Thermostat all allow you to set schedules so your home cools down before you return, warms up while you're away, and adjusts overnight — automatically, without manual changes.
A smart thermostat costs $80 to $250 installed and is one of the highest-return smart home upgrades available. It saves money every month and it's one of the features buyers specifically look for when shopping for a home in Utah County.
Practical Tips for Utah County Homeowners This Summer
Use ceiling fans. A ceiling fan running counterclockwise in summer creates a wind chill effect that makes a room feel 4 degrees cooler without changing the actual temperature. You can raise your thermostat setting by 4 degrees and feel the same comfort with far less energy use.
Close blinds on south and west-facing windows during peak afternoon hours. Direct sun through windows is one of the biggest sources of heat gain in Utah County homes during summer afternoons. Closing blinds before 2pm on south and west exposures reduces how hard your AC has to work.
Don't set the thermostat lower than your target when you come home. Per the Department of Energy, setting the thermostat to 65 when you walk in to cool down faster doesn't work — your system cools at the same rate regardless of the set point. You'll just overshoot and then warm back up.
Check your air filter. A clogged air filter makes your system work harder and use more energy to achieve the same result. In Utah County's dusty summers, filters clog faster than in other climates. Check yours monthly during peak summer months.
Schedule your HVAC maintenance before peak season. An HVAC system that hasn't been serviced runs less efficiently. In Utah County's extreme summer heat, a system running at reduced efficiency costs significantly more per month than one that's been tuned up.
What This Means for Home Value
Energy costs are a real factor in home buying decisions in Utah County. Buyers ask about utility bills. Homes with smart thermostats, good insulation, and efficient HVAC systems are easier to sell and command better prices than comparable homes without them.
A $250 smart thermostat is one of the best investments a Utah County homeowner can make — both for immediate monthly savings and for resale value. If you're thinking about selling in the next one to three years, it's worth doing now so you get the benefit of the savings while you're still in the home.
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Frequently Asked Questions
Is 78 degrees the official government recommendation for summer thermostat settings? Not exactly. The 78 degree number came from an older ENERGY STAR programmable thermostat example and has been repeated widely. ENERGY STAR has clarified it does not recommend any specific temperature. The Department of Energy's actual guidance is to keep your thermostat as high as comfortably possible — the closer your indoor temperature is to the outdoor temperature, the less your AC runs and the lower your bill.
How much money does raising the thermostat actually save? Up to 3% per degree above 72°F on cooling costs. Setting your thermostat 7 to 10 degrees warmer when you're away for 8 or more hours can save up to 10% annually on combined heating and cooling bills per the Department of Energy.
What temperature should I set my thermostat when I leave the house in Utah County? Around 80 to 85 degrees. Don't go higher than 85 — your system needs to run occasionally to maintain humidity control. In Utah County's dry climate this is less critical than in humid markets, but still worth keeping in mind.
Do ceiling fans actually help? Yes. A ceiling fan running counterclockwise in summer creates a wind chill effect that makes a room feel approximately 4 degrees cooler. You can raise your thermostat setting by 4 degrees and maintain the same comfort level, which meaningfully reduces cooling costs.
Does a smart thermostat actually save money? Yes. Per American Standard Air, homeowners save approximately $180 per year with a properly programmed smart thermostat. At a cost of $80 to $250, payback typically happens within one to two years. It's one of the highest-ROI smart home investments available for Utah County homeowners.
Does my thermostat setting affect home resale value? Indirectly yes. Buyers ask about utility costs. Homes with smart thermostats, efficient HVAC systems, and good insulation are easier to sell and tend to command better prices. A smart thermostat is a visible, tangible upgrade that costs little and communicates that the home has been well maintained.
Related reading:
- Smart Home Upgrades That Increase Home Value in Utah County 2026
- New Construction Home Inspection: The Most Common Findings in Utah County
- I Want to Sell My Saratoga Springs Home — But Where Do I Start?
- Eagle Mountain Real Estate Market Update: June 2026
- Wildfire Risk in Utah County: How Fires Start, Spread, and Get Contained
Sources: Yahoo News / Palm Beach Post — ENERGY STAR clarification: does not recommend 78 degrees or any specific temperature, 78 degree figure came from older report used as programmable thermostat example, utilities and media continue citing it, 2024; Department of Energy — Programmable thermostats: set as high as comfortably possible in summer, smaller difference between indoor and outdoor temperatures the lower the cooling bill, June 2026; American Standard Air — 78 degrees DOE recommendation, save up to 3% per degree above 72, $180 annual savings with smart thermostat, February 2026; Trane — Should you set thermostat to 78: DOE save 10% annually by raising 7-10 degrees for 8 hours, don't set above 80-85 away to maintain humidity control, reduced strain extends HVAC life, April 2026; BKV Energy — 78 degrees DOE recommendation when home, 80 or higher when away, 7-10 degrees warmer saves up to 10%, March 2026; CBS News / CNN — ENERGY STAR programmable thermostat example: 78 degrees wake up, 85 degrees day, 82 degrees sleep, $180 annual savings, OSHA recommends 68-76 for offices; AOL / USA Today — Best summer AC temperature: 78 degrees when awake per EPA Energy Star, 4 degrees warmer when sleeping, 7 degrees warmer when away, 72 degrees most popular actual setting per Consumer Reports 2021.
Written by Kat Ashby, Principal Broker and Realtor® at RootQuest Realty LLC in Saratoga Springs, Utah. Kat holds a Utah Division of Real Estate Principal Broker license (Credential #10382396-PB00) — a designation that requires demonstrated experience, additional coursework, and a separate licensing exam beyond the standard agent license. She has been actively selling in Utah County since 2020, with deep experience across Lehi, Eagle Mountain, Saratoga Springs, and the broader Wasatch Front, specializing in buyer and seller representation, new construction, and corporate relocation through Altair Global. She is fluent in English and Portuguese, earned her bachelor's degree in Psychology from Brigham Young University, and lives in the community she sells in.