Most Efficent Home Heating Strategy?

[asterion]

Being out on my own and having complete control over the furnace, I need to start heating the place up cause it's starting to get cold in here. Now, I'm trying to save as much gas (natural gas) as possible and I don't mind putting on a sweater or jacket while I'm inside the house. So, which strategy is best and most efficent:
1. Set the thermostat to something like 65 degrees or so and let the furnace work fairly continuously
2. Turn it all off whenever I'm gone and then let it come up to 65 or so whenever I'm home
3. Turn it all off pretty much all the time and bring it up to 70 or so whenever I feel cold, then turn it back off and hope all the heat doesn't radiate out too quickly
4. Buy a space heater and hope that the money spent in extra electricity is less than the amount of gas used. Move the heater to wherever I am.

[R. P. McMurphy]

Being out on my own and having complete control over the furnace, I need to start heating the place up cause it's starting to get cold in here. Now, I'm trying to save as much gas (natural gas) as possible and I don't mind putting on a sweater or jacket while I'm inside the house. So, which strategy is best and most efficent:
1. Set the thermostat to something like 65 degrees or so and let the furnace work fairly continuously
2. Turn it all off whenever I'm gone and then let it come up to 65 or so whenever I'm home
3. Turn it all off pretty much all the time and bring it up to 70 or so whenever I feel cold, then turn it back off and hope all the heat doesn't radiate out too quickly
4. Buy a space heater and hope that the money spent in extra electricity is less than the amount of gas used. Move the heater to wherever I am.

Get a programmable thermostat. Otherwise, keep it cool until you need the warmth. You will save energy by letting the place cool down but it can take a long time for the furnace to bring the temp back up. Turning it down to 50 may save gas but waiting 3 hours for the temp to come back up may not be acceptable.

[AskNott]

I agree with the prog thermostat. There's a point (8 degrees? 10?) below your comfort setting, below which your setback doesn't save money. Usually, folks have a small setback for sleep, and a bigger one for when nobody's home. If you stay up late one night for New Year or something, don't forget to override.

Running the furnace's fan all the time will even out cold spots; some folks disagree with this method.

[asterion]

Can't get a programmable thermostat, as it's a rental house and now is not the time to bring up such matters with my landlord. Nice thing is that it's a small house with the furnace underneath and the hot air coming from registers in the floor, so it shouldn't take much to heat it up.

[R. P. McMurphy]

Can't get a programmable thermostat, as it's a rental house and now is not the time to bring up such matters with my landlord. Nice thing is that it's a small house with the furnace underneath and the hot air coming from registers in the floor, so it shouldn't take much to heat it up.

Switching out a thermostat is a simple procedure. Save the old one and switch it back when you move out. Really, it only takes a few minutes. Even if you leave it and stay through the winter you will probably save the cost of the thermostat.

[scotandrsn]

My mother once rented a house whose entire 3-4 story south side was a glass-enclosed greenhouse. Sun heated up the greenhouse, a ventilation system carried the hot air to a slab underneath the house, which radiated the heat to any part that wasn't getting heat from the greenhouse directly. Toasty warm all winter! Every floor had a balcony looking out over the greenery. The gray water from the shower helped water the plants.

Of course, I could see that a landlord who won't even go for a programmable thermostat might be a tough sell on this one... but it DOES work!

[jacksprat]

Switching out a thermostat is a simple procedure. Save the old one and switch it back when you move out. Really, it only takes a few minutes. Even if you leave it and stay through the winter you will probably save the cost of the thermostat.

Precisely what I've done in my rental apartment. Lower level of a 2-story house; no storm windows; old thermostat. Switched it out. Will give the landlord a chance to purchase it from me when I leave or just take it with me. No big deal -- necessary to take control of your own living space even when renting, within reason.

Plastic insulating film over windows which aren't opened during winter. $40 oil-filled 1500W electric space heater.

[Shirley Ujest]

Prog. themostats are the way to go.


Don't even think about Turning off and then warming it up when you get back. It is fuellish.

[Una Persson]

Don't even think about Turning off and then warming it up when you get back. It is fuellish.
Given that it's been proven multiple times on this Board over the years that turning off the heat and then turning it back on when you're home does in fact save energy, what are you basing this assertion on?

[raindog]

Given that it's been proven multiple times on this Board over the years that turning off the heat and then turning it back on when you're home does in fact save energy, what are you basing this assertion on?
Before we get to having Shirley Ujest pony up a cite, how about yours?

I'd be interested to see how this has been "proven", let alone many times.

[Leaffan]

Before we get to having Shirley Ujest pony up a cite, how about yours?

I'd be interested to see how this has been "proven", let alone many times.

3 Degrees (http://www.ec.gc.ca/eco/wycd/home1_e.html)

or

A few degrees (http://www.energy.gov.on.ca/index.cfm?fuseaction=conservation.tips_heating)

This translates to about 5 degrees Fahrenheit in the room temperature portion of the scale.

Incidentally I installed a wood stove in my basement at the tail end of last winter and am amazed that my furnace has only a cumulative run time of one hour on it thus far this heating season (Ottawa). And I've only burned maybe 15 pieces of wood.

[Una Persson]

Before we get to having Shirley Ujest pony up a cite, how about yours?

I'd be interested to see how this has been "proven", let alone many times.
First off, they made the claim, so they get to "pony up" first. That's sort of the way it works in GQ.

Second, where's your cites? Are you claiming that thermodynamics doesn't work for houses and furnaces now? The heat lost between the house and the environment outside is a function of the temperature differential between the inside control volume and the outside atmosphere. The greater that heat difference, the greater the heat lost. If the house is maintained at a lower temperature through the day, then there is less heat lost. This is sort of the whole concept of programmable thermostats in the first place. Why do you think programmable thermostats save money, anyhow? They lower the temperature during the day, and raise it before you get home. That's only somewhat different from manually setting it lower yourself before you leave and raising it after you get home. And it works the same way with air conditioning too, except there is the added variable of controlling humidity, in which case it's not so much of an energy situation as a comfort and mold control situation.

Third, did you try using the Search engine here first? I know it misses a lot of links, I had to try many different permutations to find some threads, but still, there's at least some that are easy to find.

http://boards.straightdope.com/sdmb/showthread.php?threadid=52856

http://boards.straightdope.com/sdmb/showthread.php?t=139807&highlight=thermostat+efficient

And here's some sample calcs by me, using a rough example, showing you how you figure it out yourself:

http://boards.straightdope.com/sdmb/showthread.php?t=155549&highlight=thermostat

Fourth, there's always the Net. There's too many to really list, and you can dig through the DoE site for a while, but aside from some like Leaffan provided, this was my first Google hit:

http://www.consumerenergycenter.org/homeandwork/homes/inside/heatandcool/thermostats.html

So what are your cites? What is your basis for believing that lowering the thermostat does not save energy? I'd be happy to look over them, and your calculations. I expect your next post in this thread will have some sample calculations or links to such to share with us.

[Una Persson]

Before we get to having Shirley Ujest pony up a cite, how about yours?

I'd be interested to see how this has been "proven", let alone many times.
FTR, you're basically saying the same thing I am in your post over here, just for an air conditioning situation:

http://boards.straightdope.com/sdmb/showpost.php?p=6652802&postcount=6

You seem to understand at a minimum the basics (and possibly much more) and agree with what I'm saying. So what's up? Do you just want me to "prove" it to you with thermo why it works like I do to my students? If we had time we could break it on right down to the 0th, 1st, and 2nd law, and set up all our assumptions and go through the differential equations, but I'm not going to when it's already been done in simple algebra form, and I think you're saying the same thing I was (in the other thread) but from the aircon side anyhow...so where's the beef?