Which of these heating plans for our house is more energy efficient?

I’ve heard that it is better to heat up your house all at once than to heat it up a bit and maintain it.

Please check out our heating strategies and tell me which one is more efficient.

Both plans are if we are at home. We have it off if we are not home during the Day.

Currently:

  1. We turn it down to 62 F at night, sometimes even 58. We don’t care too much.

  2. In the morning we turn it up to 67. 68 if it is super cold outside.

  3. After it’s at 67, we either leave it there for awhile or let it cool to 64 or so. Then, we’ll heat it up again. Sometimes in the evening, we leave it at 67 for 3 hours or so.

Proposed system:

  1. If we are going to be home, wake up and turn it up to 72 degrees.

  2. Let it heat all the way up to 72, then turn it back down to 65 or 66.

  3. When it gets down to 66(maybe 65), turn it back up to 72 again, let it heat up. Then cool again. Repeat as long as it is needed.

  4. Still turn it down to 62 at night, of course. Or colder.

Which one is better? The proposed one or the current one?

We have decent insulation. :slight_smile:

The first one is marginally less energy costly. You lose energy in direct proportion to the difference in temperature between hot and cold. So, by maintaining a lower “hot” inside temperature, you will tend to lose less energy.

BTW - what is your heat source?

That doesn’t make much sense nor does your second scheme, the first one is best.

The most energy efficient is whatever maintains a lower temperature for the longest period. This is because of two reasons:

  1. The heating appliance runs less to reach the temperature.
  2. Less heat is lost to the outside because of the lower temperature difference between inside and out. (As beowulff pointed out.)

I think you’re doing a great job of conserving energy with the first scheme, most people wouldn’t sacrifice as much.

I think this is a corrupted (and incorrect) version of the recommendation to lower your house’s temperature when you’re away during the day and turn it up when you return, rather than leave it at the same temperature while you’re out.

Natural gas furnace. Carrier brand, year 2004.

No, I don’t think so.

Basically, the difference in my plans is this:

Currently, we only heat it to 67, but then turn it off and let it cool down quite a bit. However, we have to turn it back on again sooner than my proposed plan because we keep it so low.

In the new plan, we turn it on and let it run for longer(until 72 I guess), but then we leave it off longer because it takes longer to cool down.

Our furnace does not “throttle” either, where it blows harder when it has more temperature increase to go.

These are really both the same reason. If you had a perfectly-insulated house, you could keep it at a constant temperature indefinitely without any heat source. All that your furnace does is replenish the heat that gets lost to the environment through imperfect insulation. And that heat loss is proportional to the difference in temperature between inside and outside.

You’re right of course.

We have a programmable thermostat (I recommend you get one of those - marvelous inventions) that is basically programmed to do what you’re doing - it’s set for cold at night and during the day, and heats up for a short time in the morning and for most of the evening, when we’re actually in the house. As far as we know, this plan saves a lot of energy - we’re not heating a house when we’re not awake and around in it.

As said earlier, with a higher temerature differance more heat loss will occure. For confort I would rather have the space I am in at a constant temperature. Just turn it up to 65 degrees and leave it there. Changing the temperature up and down can cause discomfort, and the large the swings the more noticiable.

We have a programable stat. at night it drops to 60 degrees. Just before getting up it goes to 67 degrees. A half hour before leaving it dropps to 62 degrees. Then at 5:00 Pm before we get home it goes to 67 degrees. when I get home from work I do a Mr Rodgers, jacket comes off sweater goes on. For full confort I would prefeer 72 degrees.

If you get a programable stat besure it is a 7 day stat with 4 settings per dady.

Half of heating and cooling is in the mind. At work in the winter I will get cold calls for spaces that are 73 degrees tenants are freezing. And in the summer I have gotten hat calls from the same tenants at 70 degrees they are about to faint because it is so hot.