Should You Keep Your Thermostat At One Temperature?

Since heating and cooling are the largest energy consumers in most homes, small adjustments can lead to big savings. According to the U.S. Department of Energy (DOE), by lowering your thermostat by seven to 10 degrees for eight hours a day, you can save up to 10% a year on energy bills. Adjusting your thermostat takes less than a minute to do. And you can make it even easier with a programmable or smart thermostat that does the work for you. Keep reading to learn more about setting your thermostat for savings.

How Thermostat Settings Impact Energy Use

Heating or cooling your home requires more energy when the temperature inside and outside is very different. When temperatures outside are below freezing, your heating system needs more energy to maintain a comfortable indoor temperature. The same goes for summer when your air conditioner is trying to keep up while it’s 90 degrees or more outside. 

According to Newton’s Law of Cooling, you can save energy and money by adjusting the thermostat rather than leaving it at one temperature.

Newton’s Law of Cooling and Home Temperature

Newton’s Law of Cooling states that the rate at which something cools down or heats up depends on the difference between its temperature and that of its surroundings. The greater the difference in temperature, the faster the temperature will change. 

This means your heating system has to work harder to keep the warm air inside when it’s cold outside, which uses more energy to maintain. The same goes for cooling. To counteract this effect, you can conserve energy by adjusting your thermostat closer to the outdoor temperature.

Here are a few examples of how a difference in temperature impacts heat loss and energy usage. 

Constant Temperature vs. Temperature Adjustments

While some may argue that leaving the thermostat at one constant temperature is best, the biggest benefit of keeping it at the same temperature is convenience. It’s not the best way to save energy unless you have a heat pump, which is already energy efficient. 

Keeping your home at a constant temperature leads to unnecessary energy use, especially when you’re not there or overnight when you’re sleeping. The heating or cooling system continues to work even when it’s not needed, which increases your total home energy usage.

Adjusting the temperature when you’re away or sleeping can save energy and lower your bills. Your heating and cooling systems won’t have to work as hard when you lower the temperature in the winter and raise it in the summer. Programmable and smart thermostats automate these adjustments so you can improve energy efficiency without the hassle. 

What Temperature To Set Your Thermostat at When Home

You can still save energy while maintaining a comfortable indoor temperature. Keep your home around 68 degrees in the winter and up to 78 degrees in the summer for savings when you’re home.

Let’s say you set your thermostat to 70 degrees while it’s 30 degrees outside. Your home gradually loses warmth when your heating system is off. The rate of heat loss depends on your home’s insulation. The warmer the inside temperature compared to the outside, the faster heat escapes. 

In this case, your home loses heat faster when it starts at 70 degrees than it would if you had set it to 62 degrees. The rate of heat loss slows down as the inside temperature gets closer to the outside temperature, based on Newton’s Law of Cooling. This means that your system will have to run more often to maintain the 70-degree setting than it would to maintain the 62-degree temperature.

What To Set Your Thermostat at When Away 

Adjusting your thermostat while you’re away at work or on vacation can help you conserve energy and cut back your electric bills. The DOE recommends adjusting your thermostat by seven to 10 degrees when you’re not home for long periods. The longer you’re gone, the more you can adjust the temperature without impacting your comfort. 

Here are a few examples of how you could adjust your thermostat for different lengths of absence. 

• Short absence (4-8 hours): While you’re away during the day, consider setting your thermostat five to 10 degrees lower or higher (depending on whether it’s winter or summer). For example, if you usually keep your thermostat at 70 degrees, set it to 62 degrees during the winter and raise it to 78 degrees in the summer.
• Medium absence (12-48 hours): Adjust your thermostat closer to the outside temperature when you’re gone for a day or weekend, such as 60 degrees in winter or 80 degrees in summer. 
• Long absence (7 days or more): When you’re not home for a week or longer, make bigger temperature adjustments, such as 55 degrees in winter and 85 degrees in summer.

Maximizing Energy Savings with Your Thermostat

Regularly adjusting your thermostat settings when you’re home or away helps reduce your consumption and lower your energy costs. Installing a programmable or smart thermostat makes it even easier to save. You can schedule these devices to automatically adjust the temperature for you instead of manually changing it multiple times a day or having your system running when no one is home.

Smart thermostats have added benefits, such as learning your routine and making adjustments automatically. They also offer the convenience of remotely changing temperatures from your phone, which means you can make adjustments even if you have already arrived at your vacation destination.

Common Thermostat Myths Debunked

The Heating Recovery Myth

One of the arguments in the debate about thermostat temperatures is that it uses more energy to reheat your home back up to your preferred temperature rather than keeping it constant. However, this is a myth. How much energy your heating system uses depends on your home’s insulation and the heating system’s efficiency. 

Modern heating and air units efficiently warm or cool your home, using less energy than older systems. If you adjust your thermostat accordingly, you can also use less energy while you’re away. Homes with proper insulation and fewer air leaks lose heat slowly, so it doesn’t take as much energy to reheat or cool down to a comfortable temperature when you’re home.

Heat Pump Systems Should Stay Constant

The idea that you should keep a constant temperature with a heat pump system is true. The DOE recommends the “set it and forget it” approach if your home has an electric heat pump. These systems can lower the energy used to heat your home by 75%, so adjusting the temperature doesn’t save you as much as it would with a conventional heating system.  

Frequently Asked Questions About What Temperature To Set Your Thermostat To

What is the cheapest way to use a thermostat?

You can save up to 10% on yearly energy bills by adjusting your thermostat by seven to 10 degrees while away from home or sleeping. This means the average U.S. household could save up to $174 per year. 

How much energy does 1 degree on the thermostat save?

You can save 1% to 3% on energy costs by adjusting your thermostat one degree towards the outdoor temperature, saving the average U.S. home $17 to $52 per year. If you’re already adjusting one degree, going a little further leads to even more savings. 

Does a Smart Thermostat Really Help Save Money?

Yes, smart thermostats can help you save money on energy bills by automatically adjusting temperatures to your schedule, detecting when you’re away, and allowing remote control from your smartphone. Use the Energy Star rebate finder to find potential savings or tax credits on a smart thermostat.

Is it bad to constantly change the temperature on the thermostat?

Yes, constantly adjusting your thermostat wastes energy by starting and stopping the system to maintain your preferred temperature. It also causes unnecessary strain on your heating and air systems, leading to higher bills and more frequent breakdowns. To save money and energy, the DOE recommends adjusting your temperature when you’re away for extended periods rather than every few hours.