Outdoor wood boiler wood requirements

[Groo]

An outdoor wood boiler is not a very efficient way to heat (gasification will be better, but still some inherent inefficiencies), and neither is hot water in the floor of a basement.
A wild guess would be you are about 20% there for a year. To pile up 3 years worth would take quite a shed to store it all in.

 

[Rustyiron]

and neither is hot water in the floor of a basement.
To pile up 3 years worth would take quite a shed to store it all in.

I don't get the "neither is hot water in the floor of the basement" part?
Firewood cut, split & stacked (off the ground on wood pallets) will last many years uncovered, outside. A piece of old roof metal on top will make it last forever....just about

 

[teejk]

Thanks all!

Some more info:

The house is actually well insulated. Far better than I thought it would be. Out heating bill was no more that $160 (natural gas) this winter.

The basement walls are also insulated.

I know a lot of people save/sell apple wood for smokers. We downed about 50 apple trees (the land was formerly an organic orchard) to make room for the house. I have all that wood to cut up. I will likely sell 2 full cords of apple wood, but need some for the house still. For what it's worth, I still have at least 25 apple trees, and we are actively pruning and de-vining about 15 of them.

We had the boiler last winter, but it was not yet hooked up. Brand new house, still prioritizing expenses. We are hooking it up this summer to be ready for winter.

Special thanks to Billy Bee because your climate/situation is very similar.

My hope is, indeed, to get wood ready up to 3 years in advance. I regularly look at FB Marketplace and craigslist for "you come take it" deals. In the meantime, I have a massive brush pile to cut up AND a few in-the-way trees I want down.

I buy small bags of apple chips for smoking and I think it comes out to about $100,000/cord. Figure out a way to market that wood (farmers market maybe?) and replace it with something else.

 

[Jstpssng]

I buy small bags of apple chips for smoking and I think it comes out to about $100,000/cord. Figure out a way to market that wood (farmers market maybe?) and replace it with something else.

You're paying for chipping, kiln drying, packaging, distribution,etc. As with any raw material, very little of that money is for the actual wood.

 

[BLSXJ]

is there any way you can get the volume of gas you used last winter? I assume that's $160 per month, heating 6 months per year ( I used to live in Windsor). a quick google found the cost was about $3/ thousand cubic feet and your bill was roughly only 65% spent on gas... $160x65%=$104 divided by $3 = ~35 Mcf of gas per month X 6 months = 210 Mcf gas used last winter.

lets assume your gas furnace is 95% efficient, therefore 200 Mcf of gas was used to heat your home. 1Mcf of gas contains 1.037 million BTU.... so you used roughly 200 million BTU's last winter.

if your new boiler is 100% efficient, you'll need 7.25 cords of apple wood... if its closer to 80% you'll burn close to 9. FULL CORDS 4x4x8

WARNING THIS POST WAS DONE BEFORE CAFFEINE.

 

[Groo]

I don't get the "neither is hot water in the floor of the basement" part?
Firewood cut, split & stacked (off the ground on wood pallets) will last many years uncovered, outside. A piece of old roof metal on top will make it last forever....just about

you need a higher heat rise than you would by heating the air. You are also putting that heat in contact with the ground, (presumably with a bit of insulation, but likely less than the walls) so much of the heat goes into the ground. Any floor covering you may use puts even more heat into the ground. Baseboard heat with with a subfloor and carpeting would be more efficient. so would forced air.

 

[sailfast]

Properly constructed radiant under floor is more efficient than forced air.

 

[Rustyiron]

Properly constructed radiant under floor is more efficient than forced air.

That's my experience, air is a poor way to try to move btu's around. Then h/w baseboard heat needing 180* water temp range whereas radiant uses 110-115* water.

 

[Larry Caldwell]

Hi all,

I just built my house last year and am hooking up the outdoor wood boiler to get it going. I was wondering how much wood I can expect to need for a full winter. Some details:

• Region: Lower Penninsula, Michigan. Anticipate heating requirements from November to March.
• Boiler: Portage and Main EGR250 wood gasification boiler.
• Heat method: Radiant floor in-slab in basement (with insulation under the slab). Pex tubing with 10 inch spacing. Multiple zones.
• Area: 2700 square feet (house is a ranch, yes I have a glorious 2700 square foot basement).
• Wood: Predominantly oak and apple. All aged 1+ years after splitting

I currently have 5 rows of 16" x 10' x 4' wood cut and split. (266 cubic feet, or 2.08 full cords). I'm estimating I'll need 5 full cords per year. Am I close? Is anyone else in a similar climate with a gasification burner? How much do you burn?

Thanks,
Don

Interesting system. A 250k, 160 gallon boiler would boost water temp almost exactly 100 degrees an hour. Are you relying solely on the boiler, or do you plan hot water storage between the house and boiler? Coils in a storage tank would give you almost limitless domestic hot water. Hour long showers. Fill the bathtub. Fill the hot tub.

A 3 gpm pump on the boiler would take care of the output, but the problem with wood boilers is that the output is uneven. You are not always going to want to go outside to stoke the thing, or even be home to do it. A friend in northern Idaho built a hydronic system that relied on thermal mass of concrete for heat storage, but the concrete in the basement was a foot thick. He also had a 300 gallon (about two of your boilers full) hot water storage tank with coils for hot water. Don't forget to keep your chemicals balanced. The PEX may survive neglect, but the flame tubes won't.

I would also recommend a propane log lighter option, if it is available. You really don't want to be out there trying to get the thing lit in a 30 mph wind at 30 below. As for wood, start with 10 cords and see how much you have left in the spring.

 

[Groo]

Properly constructed radiant under floor is more efficient than forced air.

how? radient heat also has to heat the air, but the heat exchange is putting some heat into the earth instead of direct into the air.