Dear Eartha, I’ve heard opposing views on the best way to use your thermostat for energy savings. Some say it’s better to turn it down when you’re away and others say it’s better to leave it at a constant temperature. Can you help settle this debate?

The snow is falling fast, and winter has officially made its presence known here in Summit County. That means we’re all thinking about how we can stay cozy inside. But we still want to save energy and money. Your instinct to turn to your thermostat is a good one. These devices put information and control at your fingertips to help you manage the comfort and energy use in your home. So let’s dig in and figure this out once and for all.

Thermostat setbacks

You might wonder why you would turn the temperature down from your normal comfort setting. This process is called a setback. Temperature setbacks are useful during times when you are away from home or asleep because they reduce energy used by your heating system when it isn’t needed. In fact, the U.S. Department of Energy reports that for every degree you lower your thermostat you can save 1% on heating costs annually (the setback needs to be for at least eight hours a day). Even better, decreasing indoor temps at night provides multiple benefits, including better sleep. The ideal range for deep, restful sleep is 60-65 degrees.

Now, exploring why setbacks work can quickly turn into a physics lesson, but here’s the basic gist: Heat always moves from hot to cold, like from inside your heated home to outside, where it’s cold and snowy. How fast it moves is directly related to the temperature difference between two points. So, when you set your thermostat to a lower temperature in the winter, you decrease the temperature difference between your house and the outdoors, and so your house loses heat to the surrounding environment more slowly. This is another reason why sealing up drafty places and insulating your home really well is so important.

Is a constant temperature better?

The counter argument is that keeping your thermostat set to a constant temperature is more efficient because heating systems might work harder to recover after a setback. Generally speaking, there is no working “harder” for heating equipment. These appliances are designed to output a certain amount of energy. That energy is constant whether you’re increasing the heat by 2 degrees or 10 degrees. What changes is the amount of time your equipment spends actively heating.

The bottom line is that the energy you save by turning your thermostat back eight hours a day is far greater than the energy it will take to reheat your space to your ideal temperature. 

Got in-floor radiant heat? There’s a lot more nuance to these heating systems based on the overall efficiency of your house, flooring type, etc. It’s true that radiant systems take longer to heat a space compared to forced-air or baseboard heaters. Setbacks can still work if you plan enough time for your home to reheat, but this might require more trial and error on your part to figure out what works best for you.

Smart thermostats

Not all thermostats are created equally. Some of the strategies I’ve mentioned can be done manually, but others are better left to automation. This is where programmable thermostats shine. Even better, smart thermostats have internet capabilities that allow them to be controlled remotely, learn and work with your heating system, and even account for local weather patterns.

If you don’t have a programmable thermostat, Xcel Energy offers discounted models to customers. Keep in mind that not all heating systems are compatible with programmable thermostats. If you have electric baseboard heaters, contact High Country Conservation Center for recommendations that will work for you.

Have we settled the debate? Setbacks will save you energy and money without sacrificing comfort, so long as you are strategic with the schedule of your heating system. Get started by experimenting with different set points and heating schedules to see what works best for you. You might even find yourself more rested and energized after a cooler night’s sleep.