The CCHT twin house facility in Ottawa, CanadaTwo weeks ago in this blog I tried to answer the question, Do compact fluorescent lights (CFLs) save energy overall? Even though CFLs contribute a lot less heat to a house in the winter, compared to incandescents, CFLs still save energy overall, even in places like Anchorage, Alaska. Thanks to the folks at the Canada Centre for Housing Technology (CCHT) who did the research to answer that question.

The Department of Energy, the Environmental Protection Agency, and others recommend that we set our thermostats at 68°F in the winter and 78°F in the summer. Some people are comfortable at home with these temperatures and some or not. So how can we save energy and still be comfortable?

Besides recommending that people replace their incandescent bulbs with CFLs, we at Home Energy also encourage people to turn their thermostats down when they are away from home during the winter, and to set them up when they are away from home in the summer. Both actions are supposed to save energy. But do they? It’s not really that clear. For example, if you set your thermostat at 60°F before you leave for work in the morning, and then set it at 68°F in the afternoon when you get back, does your furnace use more energy raising the temperature of your house from 60°F to 68°F, than it saves by having the temperature at 60°F all day?

Once again the Canadians have come up with an answer. Marianne Armstrong and her colleagues at CCHT used the twin house research facility to show that thermostat set backs in the winter and thermostat set forwards in the summer really do save energy.

In the research house where they set the thermostat back to 64°F at night and during work hours, from 72°F, it saved more than 10% on heating costs compared to the house that was set at 77°F all day and night. A 61°F setback saved more than 13%.

In the summer, a set forward to 77°F at night and during work hours from 72°F saved 11% on cooling costs. Now for the big winner: Setting the thermostat up to 75°F all day and all night saved 23% of cooling costs compared to the house set at 72°F. That’s a savings of about 8% for every degree adjustment.

If you lower your thermostat a few degrees when you are away from home this winter, or when you are asleep, you’ll save energy and money. If you set your thermostat up a few degrees when you are away from home or asleep this Indian Summer, you’ll save energy and money. And you won’t be uncomfortable.

No, this is not Big Brother. Credit: Jim GunshinanThe answer to the question, Who controls your thermostat?, which I raised in an earlier post, is now clearly answered. You control your thermostat!

The California Energy Commission (CEC) was to require, as part of the 2008 Title 24 building standards, that all new homes be outfitted with programmable communicating thermostats (PCT). The PCTs would allow a utility to remotely control your thermostat during power emergencies, especially during hot summer days when air conditioning use causes electricity demand to peak. By cutting peak electricity demand in this way, California could potentially avoid rolling blackouts and even eliminate the need for building expensive new “peaker” power plants, or firing up old, dirty plants just to meet an afternoon’s demand for electricity. But after a chorus of criticism from individuals and groups around the state, CEC has dropped the rule from the standards.

From the CEC Web site:

“There has been considerable discussion concerning programmable communicating thermostats (PCT) and their proposed inclusion in the regulations for the 2008 building standards. On January 15, 2008, the Energy Commission’s Efficiency Committee (Commissioner Rosenfeld and Chairman Pfannenstiel) directed that PCTs be removed from the proposed 2008 energy efficiency building standards.”

News of Home Energy’s and my support in particular for PCTs made it’s way into some online discussion boards and we felt the backlash. I’ve never been called a fascist before! I mistakenly believed that under the new rule, a utility would not be able to fiddle with your thermostat without your permission, even in an emergency. But if I looked carefully at the proposed standard, I would have read, “The PCT shall not allow customer changes to thermostat settings during emergency events.” I was wrong.

So, Big Brother will not be controlling your thermostat anytime soon. That’s a good thing, and, in fact, the CEC now agrees:

“Technology can be a powerful tool in managing our energy use. However, it is of utmost importance that consumers make their own energy decisions.”

Jim Gunshinan is Managing Editor of Home Energy Magazine. He holds an M.S. in Bioengineering from Pennsylvania State University, State College, Pennsylvania, and a Master of Divinity (MDiv) degree from University of Notre Dame.

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