Energy Smart Tip - Set Thermostat Back/Up 10-15° to Save 10% on Heating/Cooling
By turning back/up your thermostat 10-15° for eight hours overnight when your building is unoccupied, you can save 10% on your heating and cooling bills (about one percent is saved for every one degree setback/setup for eight hours or more).
Option 1: Turn Back Thermostat Manually Every Day
One option is to remember to turn your thermostat down before you leave every day and up when you arrive every morning. Energy Star provides tips for manual setback/setup.
A typical overnight setback temperature for the winter heating season is 62° (when heating a building to 70° during the day) and a typical setup temperature for the summer cooling season is 82° (when cooling a building to 78° during the day). Take into account your building needs when deciding what setback and setup temperature will be right for you. Setting a temperature too low may result in frozen pipes.
Option 2: Install and Enable a Programmable Thermostat
One way to get the building to save energy automatically is to install and program a programmable thermostat. These thermostats allow you to tell your building to be one temperature during your operating hours and another temperature during your off hours. It is possible to set a thermostat so that, when you arrive in the morning, the thermostat will have warmed or cooled your building to a comfortable temperature. Images of a programmable thermostat are available from the U.S. Department of Energy website.
If you already have a programmable thermostat but need assistance programming it, Energy Star provides tips for using your thermostat.
There are a few different types of programmable thermostats depending on the schedule you would like it to keep. Energy Star has a guide for choosing the thermostat that is right for you.
When purchasing a programmable thermostat, be sure to look for the Energy Star label.
Energy Star provides this PDF list of qualified programmable thermostats. The site also provides a store locator tool.
The site has posted a guide for installing the thermostat - yourself, or when you should call an HVAC contractor to help you. Install thermostats away from direct sunlight, drafts, doorways, skylights, and windows, and be sure to place it so it is conveniently located for programming.
Don't I make my furnace or air conditioner work harder? Doesn't it save energy to keep it running constantly? I am worried it will draw a lot of energy in the morning when I turn up/down the temperature again.
No. From the U.S. Department of Energy: "This misconception has been dispelled by years of research and numerous studies." The basic idea is that you save fuel based on the length of time your furnace gets a break. Your furnace uses about the same amount of fuel to reheat the building (from 60 to 70) as you save by letting the building drop to the lower temperature (from 70 to 60) - but once the building drops to the lower temperature (60) and stabilizes at the lower temperature, it is cash in your pocket. That is why it is important to setback temperatures for longer periods of time, such as overnight and on weekends.
With on peak/off peak or demand rates, try to set the temperature so you are not cooling all the way to "normal" temperature during on-peak times. This should help save you money.
What if I have baseboard heating, steam heating, radiant floor heating, or a heat pump?
Baseboard electric heating systems will require a special line-voltage thermostat. Only a few companies manufacture line-voltage programmable thermostats.
Steam and radiant floor heating systems are slow to respond and require a slightly different approach. Some special thermostats are available that track the performance of your heating system and figure out when to turn the system on or off to achieve comfortable temperatures. It is also possible to do this manually (leaving 2-3 hours lead time whenever you want to change the temperature), but may require some guesswork.
Programmable thermostats are not designed to work with heat pumps and probably will not be a good fit for these systems.
Resources:
U.S. Department of Energy - Thermostats and Control Systems (residential-focused, but applies to small businesses, too)
Energy Star Programmable Thermostats
For more energy efficiency tips, check out Quick Tips for Energy Efficiency.