Programmable Thermostats

A thermostat can do a fine job of keeping your house at a constant temperature, but having your home warmer than it needs to be when you are asleep or away is wasteful. If you are still using an analog thermostat it’s time to “get with the program”! Installing and using a programmable thermostat costs little (or nothing!) and can reduce your home heating bill up to 15%, perhaps saving you around $300 every year.  Recent models are easier to use, and many people feel that less heating or cooling at night can be both more comfortable and healthier.

There are a couple of basic types:

  • Tier l thermostats: A programmable automatic-setback thermostat adjusts the temperature based on time of day. Set it to turn the temperature down at night and when you leave for work. You can save 3% heating energy with every 1 degree! That’s 10% savings for every 8 hour period of 10 degree setback. You can also adjust the temperature way down while you are away for more than a day by using the Hold temperature function.
  • Tier II & III thermostats: The latest smart WIFI thermostats are remarkably easy to use and offer maximum energy savings. They can learn from your behavior to create automatic setbacks and bring the house back to temperature when you need it. A motion sensor knows if you come home early, and a wireless network interface allows remote control from a computer or smartphone, as well as access to local weather data. These thermostats are often available at steep discounts and can get installed for free if you schedule an energy audit.

Recommended Actions:

  1. If you already have a programmable thermostat, make sure it is programmed properly. It should set the temperature down (in winter) by 8 to 10 degrees for 8 hours at night, and also during the day when no one is home. Make a cheat sheet for changing the programming if you need to for other family members to use.
  2. If you don’t have one, find out about the rebates available, choose a model of thermostat that is right for you, buy it and get it installed. Typical savings from the different types of programmable thermostats:
Type Energy Savings $ savings/year CO2 Savings per year Advantage
Tier l 10%-15% $150-$200 1.5 tons Big return on small investment
Tier ll&lll over 15% $200-$300 2.0 tons Maximum ease of use

Financial Considerations

Relatively speaking, getting programmable thermostats purchased and installed is really inexpensive, and the savings can be high enough to cover the cost in the first year.

Incentives

There are current discounts and incentives available on a variety of thermostats:

  • Mass Save: incentives change often, so check-out the utility’s current offers. If you schedule a free energy audit, you get a rebate for wireless-enabled thermostats and free installation. The incentives apply to certain models and up to 2 per household.

Environmental Benefits

Since heating and cooling are a large fraction of one’s home energy use, reducing emissions by up to 15% is huge, typically 1.5 tons of CO2 per year.

FAQs

Q: Is this something we can do if we are renting?   A:  Yes, and it will pay back quickly if you pay for heat and/or electricity.  If not, let your landlord know they could save on utility bills.  The lowest priced units are around $20.

Q: Will a programmable thermostat work with all types of heating systems?  A:  Most.  One exception is heat pumps, which may become less efficient if the temperature is set back.  In this case it is generally better to set one temperature, and only turn the heat down if you’ll be away for a day or more.

Q: How difficult is it to install a programmable thermostat?   A:  Tier-1 thermostats are simple to replace; wi-fi-enabled thermostats require a third wire which may be missing if you are replacing an older thermostat.  You may be eligible for free installation, avoiding any such difficulties (see below).

Resources/Links

  1. Energy Federation Inc. Guide to Selecting a Thermostat
  2. MassSave thermostat incentives