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[Ridgekid]

In the last 24 hours the weather dipped to the lowest numbers this season.  So naturally I thought it meant time to put more than normal wood into the Green Dragon. Doesn't seem to be the case.

In the last 36 hours the Green Dragon went through 14 Burns on 12 pieces of wood. The last three pieces being added at 9AM this morning. My guess she is burning some of that stored energy (creosote) that she formed over the last few weeks. Firebox sure looks better this morning.

[Scott7m]

The extra btu's had to come from somewhere

[Ridgekid]

I agree. Or it's more efficient in colder weather? 

In the last 56 hours I went through 20 burns on 18 pieces of wood. It's getting close to adding some more wood. I can tell by the amount of smoke, or lack of smoke, she will need wood soon. Thermostat is set at 73* during the day and 71* at night.

At this rate, I'm burning less wood then my indoor unit did. Of course the indoor unit could not be controlled by the thermostat and we were usually roasting. Temperature control was shedding clothes, cracking windows.

With a indoor unit the infamous pot of water had to be put on the indoor unit to maintain some moisture in the house. Now we don't have a issue. Not one static shock from it being too dry.

In short, I wish I would of done this years ago.

[BoilerHouse]

It's still a bit early to draw any conclusions.  You should have a good handle on it by spring.  I have found your data quite interesting and have started to take some of my own.  The best thing about hard numbers is that it is easier to gauge any changes that one might make rather than relying on a subjective memory.  I can't speak for everyone of course but I can say my memory is excellent but unfortunately it's also short. 

[MTJAG]

Without a doubt, tracking heat demand and wood usage that RidgeKid provides is a huge help.  Quite frankly, I get surprised all the time with my 5036 and the amount of wood it uses when the temperature drops into the single digits.  You are rocking along with overnight temps in the 30's, then you have a cold front that drops the overnight temps into the single digits and the day time temps in the 30's and my OWB doubles consumption, or at least so it seems.  So, to track this provides some realiable data that can at least give us a reasonable benchmark of usage.  Of course we all have the variables of home construction, wood speicies, and wives to consider.

[Ridgekid]

Good points.  Don't forget your elevation is a factor too!  You running with or without restrictor plate?

[Scott7m]

The stove shouldn't know that it's colder unless it just never completely seals off.  Its not rocket science.  Wood has a btu per pound rating and the colder it is outside the more btu's your going to have to make.

Now you could see very slight differences based on a cleaner firebox  and such but I think your research could be taken a step farther.  How about weighing your wood each day and recording the number of pounds of wood your putting in your stove, and if you have a moisture meter use it and record that as well.  Recording it in terms of "pieces" is a very broad term because they vary greatly in shape/weight/moisture and that all changes.    So to get down to some harder data take a scale out and weigh your wood.  Ill do it too!  I'll start doing it when I quit burning this junk I am now, well be able go tell a lot more about the data when we get it down to a pound.

[Ridgekid]

Point well taken. I can weigh my wood the next couple days and check moisture, but only on the ends. I recently provided my moisture content report at another post recently.

I should point out my wood is 95% oak. Maybe I should of mentioned that before we got this far.

In any case- Game On!!

[Scott7m]

Ridge kid, I just read my post and I was like, "it sounds like I'm challenging him to a duel" haha not the case

I was trying to say if your going to do this amount of work in this stuff,weighing the wood would give us a lot more valuable info.  We know what btu per pound that wood is, well research to see what % moisture content affects that, I'm sure wilie has some numbers.  But it will take your research to the next level. 

Burning oak, oak in general should average about 25 million btu per cord.  White oak according to most is around 26.5 and your other oaks are around 23-25, so 25 million or there about. Hickory is the best you'd have access to and it's right around 30 million btu per cord. 

[Ridgekid]

Those are good numbers. Can you break that down to BTU per pound? 

Wish I had more time for this but two days is about I can do this weekend. Hopefully that can give us a idea of what's really going on.

[Scott7m]

I'd like to do it over the course of 2 months, Jan and feb.   

Yes wood is 8660 btu per pound at 0% moisture content.

So if you have 20% moisture content, So if you had 1.25 pounds of wood at 20% you have about 1/4 pound of water and 1 pound of wood. So, at 20% moisture content the available btu is around 6930 or so. 

[Scott7m]

Also keep in mind that wood is wood.   Oak, pine, walnut, hickory, elm, apple hickory, Osage orange, no matter what wood it is!  It's still wood!  The only thing that changes is the density of the wood, better firewood weighs more because it has more fiber. 

For example:  A cord of seasoned white oak is around 3700 pounds, a cord of Cedar is only around 2000 pound.  Each contains the same number of btu per pound, but the denser wood has more btu.

Live oak is supposedly the best firewood but only grows out west, it's 4880 pound per cord dry or almost 37 million btu per cord

Osage orange is the best in the eastern parts at 4700 pounds a cord or around 33 million btu per cord

[willieG]

http://hearth.com/econtent/index.php/articles/heating_value_wood

[mikenc]

http://hearth.com/econtent/index.php/articles/heating_value_wood

quite interesting always thought red oak better than white oak and both better than apple because of how it feels after dried. red oak always seemed heavier after it was dried. never weighed on scales nor compared moisture content. maybe it takes red oak longer to dry out which makes it feel heavier.

Ridgekid keep up the good work,your data will be helpful to OWB owners.

I think scott is right on, going by weight would give more realistic data of wood consumption.

[martyinmi]

Morning all,
   I had a friend give me about 1/3 cord of black locust in early February of last year. It had been seasoned for a little over 2 years. That species gives off a lot of heat! I've never burned anything that burned so long and hot. None of the locust species are on Willies list.
   I read somewhere that there a few exotic species whose BTU content is a little over 9000. If I remember there are a few that are right around the 8000 mark also.
   My uncle retired from Dow Chemical as a chemist. We were talking about BTU's and such a few years ago and he made this comment:"If I were dried down to 20%, I'd give off about the same amount of BTU's/pound as a gnarly old swamp oak. In fact, most any carbon based life form will".
  Not to gross anyone out or anything, but I've gasified a couple different animal species in my Empyre 100 last winter. Free heat- no smoke! That's how us northern rednecks roll sometimes.

   Marty