Save $$$ - Heat with Wood

[Deere Dude]

My fireplace is probably 75%? efficient which means while burning a lot of heat goes right out the chimney, but the fireplace is air tight so no room air, or not very much anyway, goes up the chimney. It has a duct drawing in outside air for combustion so very very little inside air is lost.

Don't know about 75%. A fire place chimney always has a vacuum . Without glass doors,or adjusting the damper. There's no way to stop the surrounding air within the home from being pulled up the chimney
Not much one can do to make an open fire place more efficient

A open fire place is a large vacuum.
A fire place insert is a much better heat source / value for your home than an open fire place.

I just checked the owners manual; 77%. It is an zero clearance insert with wood framing around it. But I am sure the 77% depends on type of wood, length of fire etc.
You are correct for an open door fireplace, but that is not mine. Even still, when burning, I would think most heat from the fire itself goes out the chimney

Mine has air tight doors so room air cannot escape, and we burn with the doors shut and they are also shut when not burning. Combustion air needs to come from outside through a 4" duct running to the base of the fireplace.

 

[LD1]

I agree that "most" woodburners are 50% or in that ballpark.

As someone earlier mentioned...its not just the heat loss up the chimney. All that air/smoke going up the chimney needs replaced. That draws a vacuum on your house and sucks in cold air from window seals, door seals, everytime a door is open, etc.

The most efficient setups do indeed draw combustion air from outside. You still loose heat up the chimney.....but you are using outside air for combustion, rather than air that you already put energy into to heat. Those get to 75% ballpark.

Can one save money heating with wood......yea, maybe.

But all this talk about cutting your own, free exercise, etc. You still have to assign a cash value to the wood. Whatever the going rate is in your area. Then compare that to your other options for heating. Once you assign a cash value to the firewood, you will see that the savings is little. You can still cut and get all the free exercise you want. Just sell the firewood. IE: Just because the wood was on your land and cost you nothing but time to cut....it still has value that must be factored.

Here is some math....

Average cord of firewood is 24M BTU. Average furnace is 50% efficient. And lets say you burn 6 cord a year. That equates to 72 million BTU's required to heat your house.

Propane furnaces are ~95% efficient. And a gallon contains 92k BTU. So to get the same BTU's, you would need 824 gallons of propane to replace that 6 cord of wood.

If you have electric resistance heat, there is 3.41 BTU's in a watt. So that 72 million BTU's needed would require 21,000 kwh of power.

If you have a good heat pump....those are about 3x's more efficient than resistance.....so about 7000 kwh of of power.

So how does this all compare......no idea. Firewood cost, propane cost, and electric cost are different everywhere.

Around here....firewood is $160/cord, electric is 0.12/kwh and propane is ~$1.30/gal

So to heat this house that requires 72 million BTU in my neck of the woods would cost
$960/year with wood
$1071/year for propane
$2520 / year for electric resistance heat
$840/year for a heat pump

Not trying to talk anyone into running out and installing a propane furnace or heat pump. Just trying to make you realize that heating with wood isnt as big of a savings as many make it out to be. Because even though you dont "pay" for wood.....it still has value. And that MUST be factored into the equation.

I put in a geothermal. This is after heating with wood for the first 2 winters after I bought the house. The value of wood would have to be under $100 per cord for it to save me money over my geothermal. But since I can sell as much wood as I can cut at $160/cord, I'd be LOOSING money if I burnt it in my house.

And cutting wood.....it becomes a whole lot more enjoyable when your out there doing it because you want to..... rather than because you "have" to

 

[square1]

Have to agree with LD1. I burned $400 worth of wood a year and saved ~$200 BEFORE the $120 solid fuel rider the insurance company tacked onto the home owners policy. Dollars ahead to sell the wood I process for exercise to someone else that wants to save money burning wood.

 

[dodge man]

I don’t agree with putting a dollar amount on “free” wood other than actual cost such as saw, splitter and fuel. You do need to put a value on your time. I can’t imagine having to cut wood for heat. I agree, that would take the fun out of it.

 

[Deere Dude]

Can one save money heating with wood......yea, maybe.

But all this talk about cutting your own, free exercise, etc. You still have to assign a cash value to the wood. Whatever the going rate is in your area. Then compare that to your other options for heating. Once you assign a cash value to the firewood, you will see that the savings is little. You can still cut and get all the free exercise you want. Just sell the firewood. IE: Just because the wood was on your land and cost you nothing but time to cut....it still has value that must be factored.


And cutting wood.....it becomes a whole lot more enjoyable when your out there doing it because you want to..... rather than because you "have" to

LD1, Don't try using logic on me, it ain't going to work.

I enjoy cutting and splitting wood for myself or my friends, but I would never cut and split it to sell it. That is somebody elses gig. I don't like to cut and split that much plus I don't need the money that bad.

If I used my regular heat pump to heat the whole house I would set the thermostat and 67 deg and leave it there except maybe for sleep and I would turn it down to 60 deg. The whole house would see a rise in temperature.

But with a fireplace I have no problem heating the living room to 75 deg and maybe up to 78 at times. Then I can enjoy and lounge around in a nice warm house, at least a couple rooms near the fireplace.

 

[jk96]

I don稚 agree with putting a dollar amount on 吐ree wood other than actual cost such as saw, splitter and fuel. You do need to put a value on your time. I can稚 imagine having to cut wood for heat. I agree, that would take the fun out of it.

LD1 explained it very well why there is a dollar amount on "free" wood.

I put in a geothermal. This is after heating with wood for the first 2 winters after I bought the house. The value of wood would have to be under $100 per cord for it to save me money over my geothermal. But since I can sell as much wood as I can cut at $160/cord, I'd be LOOSING money if I burnt it in my house.

That dollar amount is whatever amount you could sell the wood you are burning to someone else instead of using it yourself. That has to be factored into what you "saved" over electric or propane to get a true cost savings of burning wood.

I'm in the same boat as LD1. We have a very well insulated home with geothermal but we still burn wood because we enjoy it.

 

[3930dave]

I like geothermal, and mini-splits.

With a long cold heating season, my preference with wood is an outdoor boiler. Fire liability doesn't change, and you can heat hot water too.

Was impressed with this line when I saw it at a Home show a few Winters back. Local electrician retired and moved to far northern Ontario. He installed one of the P&Main boilers, and really likes it.

Portage & Main Boilers - Ultimizer Wood Series

For big operations, they also have large bin/auger systems (common in Europe) that will handle various types of biomass.

Rgds, D.

 

[LD1]

I don’t agree with putting a dollar amount on “free” wood other than actual cost such as saw, splitter and fuel. You do need to put a value on your time. I can’t imagine having to cut wood for heat. I agree, that would take the fun out of it.

You have to assign a dollar amount on the wood or you are just fooling yourself into thinking you are saving money when you really might be loosing money. Just depends on what firewood, and alternative fuel sources sell for in your area.

Don't believe in the logic of "well I keep it warmer and therefore more comfortable to lounge around with wood". A heat pump, Geo, propane, natural gas, electric, etc. All capable of doing the same thing.

Cost more you say?....well remember, wood has a dollar value to. So the more you burn, the more you spend.

Like I said, a cord goes for $160 here.

I enjoy cutting.

So I can either burn it in the house and deal with the mess, or I can sell it and buy a cleaner heat. Then I don't have to ever worry about a chimney fire, added ins cost, fire going out when gone all day, and never have to worry about running out of wood. Therefore I can cut whenever I want, and not because I must to stay warm. Whole lot more enjoyable and relaxing doing something just because you enjoy it, rather than because you have to.

 

[/pine]

A question for those that sell cord wood...do you pre-stack the wood to know when you have a cord?
Do you use a predetermined size container like a truck bed or trailer?

Did you first stack a full cord and then load the container?

I realize every split is not the same size but it can be averaged...anyone have a loose/rough idea of a count on the number of "average sized" splits in a cord?

 

[Oaktree]

Around here....firewood is $160/cord, electric is 0.12/kwh and propane is ~$1.30/gal

So to heat this house that requires 72 million BTU in my neck of the woods would cost
$960/year with wood
$1071/year for propane
$2520 / year for electric resistance heat
$840/year for a heat pump

I noticed you didn't include oil as a heat source. Dunno about where you live, but here it's pretty much the only other practical alternative. The pricing on both oil and propane fluctuate considerably...they've both been sort of low past few years, but that can (and usually does) change quickly.

I buy log-length grapple loads every 3 years or so and cut/split it myself. Unfortunately, most of the woods on my property consists of pine, spruce or poplar...none of which are worth the bother. I used to be able to get a permit for "free" dead-and-down wood in the national forest (I'd go where it had been logged recently and cut the tops, branches, etc.), but ever since they put in a couple biomass power plants in the area, all that gets chipped.

I can稚 imagine having to cut wood for heat. I agree, that would take the fun out of it.

Each to their own. I enjoy it, and will continue to do it as long as I'm physically able. Great excuse to get outside in the fresh and get some exercise.

One nice thing about wood heat no one's mentioned so far is somewhat intangible, but the house just feels warmer. A thermometer can read the same temperature when we run the oil furnace, but the house doesn't feel the same.
The woodstove hearth is a great place to dry boots, gloves, etc...nice & warm when you put them on. :thumbsup: I love it, wouldn't dream of heating any other way.