Cost efficiency - electric space heater versus whole home hot air propane heating?

[Arlen Holder]

I have a large home and no money (retired too soon, I guess). Only 4 people in the house - 3 bedrooms in use, all on different floors. Multiple furnaces involved. Hot air.

Propane. About 3 bucks a gallon (or so). Tiered pricing on electricity - about 45 cents for the last kilowatt in the month and about 15 cents for the first kilowatt (very hard to average as it depends on many factors not the least of which is time-of-day use).

The question is whether I should buy at Costco 3 space heaters. Or just use the hot air heat sparingly.

The thermostat setup is the old style, Honeywell, mercury. It doesn't lend itself to timed automation. I'm not asking about a timer anyway unless it's the obvious answer.

Just asking one basic question, where the answer can only be "in general". o In general, is it cheaper to manually turn on and off the heater, or, o Do space heaters have their place in this cost-conscious scenario?

[gfretwell]

A lot depends on where you live but the 45 cents screams California. (North or South?) Here in Florida my power is around 11 cents a KWH and we have toaster wire heat in the central system so it makes perfect sense to run a 1440w heater in the room we are in and leave the central system off. We just let it get cold at night and snuggle up under a blanket but cold is a relative thing. Pipes don't freeze here and the heating season is days, not months.

[Ed Pawlowski]

Electricity is expensive. I'd not do it. You can plug i n fuel cost numbers here to see the comparison.

Even at 15 cents the propane is cheaper at 25 or 30 cents you are taking a bath.

A programmable thermostat can help if you have a regular schedule. Heat comes on 15 minutes before you get up, but there is no reason not to do it yourself on your schedule for the day.

Close the register in rooms you don't use if you can and keep the door closed. Get three good blankets.

If it was one room, there may be savings, but three rooms will really suck down the money.

[trader_4]

An automated thermostat will also set it back at night, while without it there are likely days where people forget. But the nicest part is what you say, where it fires it back up before you get up. The better new ones have adaptive recovery, where you just set it for 70F at 7AM and it figures out how much earlier to get the system started based on the temp delta, how much it's been running, previous history, etc.

Probably right. The exception might be if you could limit it to one of the radiant type electric heaters that points at one person and just warms you, without trying to heat the whole room. He could spend $20 on a KillaWatt meter and experiment. The meter even lets you put in the cost of electric and it will tell you how much it's costing to run whatever you plug in by the hour, day, month, etc.

Also more attic insulation, if it's needed, has a good payback, as does, fixing any drafts around door trim, windows, etc.

[Mark Lloyd]

[snip]

I like having it colder at night, and using a blanket. At least in the winter when I'm not paying to be cold.

BTW, rates have gone up here. My last bill shows 12.7 cents per kWh (the real value, actual bill divided by usage).

[Frank]

Distribution of heat in my house is not uniform plus my wife likes it warmer than me. So she often uses a space heater in a room where she feels cold. I figure that would be cheaper than heating the whole house an extra couple of degrees.

[gfretwell]

Same here. We are getting free A/C right now instead of the mini split my wife runs at 66 in the bedroom at night.

[Arlen Holder]

You can't imagine how many of those "furry" blanket I bought at Costco when they went on sale! I must have bought at least a dozen!

I tell everyone that the blankets save their price in just one night, but I really do not know how much propane is saved by not running the furnace for

12 hours.

Do you?

How much does a typical propane furnace burn in gallons overnight?

[Arlen Holder]

Propane is more expensive elsewhere, I'm told. Much cheaper here.

Car insurance is more expensive elsewhere, I'm told. Much cheaper here.

Yet...

Gasoline in California is super expensive compared to other US states. As is electricity.

Why? I don't know why.

Silicon Valley.

In general, is the heating of a room better than the heating of a house? The comparison assumes a whole-house heater with ductwork that can be closed off of course to the non bedroom rooms.

I don't know if that ductwork closing off really makes any difference in costs. I don't know how to tell. The furnace seems to run the same amount of time per cycle as far as I can tell from memory (it's not yet winter) whether the pushers are closed or not (I don't think the pullers have closure tabs).

If electricity were dirt cheap like you have at 15 cents or below, that would make things easier but here it starts low like that but it ramps up really fast.

Every house gets the same quota if it's gas heated. It doesn't matter how many people or how big or small the house. The quota is exactly the same for every house they tell me. So you use up that quota of 15 cent electricity in the first week or two. Then it ramps up such that by the last week, you're at 45 cents or more.

Then there is the time of day stuff. So it's complex.

I just want to know, in general, what most people feel are the tradeoffs. The math is too hard because the data is not there for usage.

In general, is the space heating more efficient than whole house (assuming that you have to heat the space a lot in that case).

[Nikola Tesla]

Read your electric meter every hour and then you'd know exactly how much your using and when you are using it.

[gfretwell]

If you are only heating one room and only while you are there, maybe an IR heater, it is definitely cheaper than running the whole house system. Even trying to duct off unused rooms is still not anywhere close to just doing the rooms you are physically in. Furnaces are most efficient moving all the air they can. Choking it off hurts efficiency and could hasten burning out the heat exchanger unless you are also dialing back the burner.

One option you might look at is a mini split heat pump. As I recall it really doesn't get that cold there so a heat pump might make sense.

[gfretwell]

If they have upgraded your meter to a smart one, that hourly use is probably on the PoCo web site. I can get reports of my usage sliced and diced several ways even down to fractions of an hour.