Which one?
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MountainStoveGuy
Minister of Fire
ironic conversation, lets assume there both EPA appliances. I would go with a stove, more surface area for heating then a fireplace.
Corie
Minister of Fire
Todd
Minister of Fire
Need more info. But I would say a stove placed in the center of your home would be the most efficient.
I think the stove has it hands down for efficiency if we're talking wood burning. But there may be a good compromise in a nice stove that lets one burn with the doors open (with a screen in front).
Todd
Minister of Fire
If you really want to open a can of worms ask which type of stove is more efficient, catalytic, non cat, or new everburn technology?
MountainStoveGuy
Minister of Fire
Ohh lets open it, i dont think she is coming back. what is more efficient, everburn, non cat or cat. I would say non cat is more efficient if you average all the people who burn all the types of stoves. Non cats never forget to get engaged.
Corie
Minister of Fire
well those are two different things MSG.
Efficiency is how good something is at converting the heat energy put it into heat energy put out. It has nothing to do with being engaged or not.
I'm going to disagree and say that a properly designed stove, with a new or relatively new cat combustor is more likely to operate at a higher efficiency than a non-cat stove putting all user error and other external factors aside.
Efficiency is how good something is at converting the heat energy put it into heat energy put out. It has nothing to do with being engaged or not.
I'm going to disagree and say that a properly designed stove, with a new or relatively new cat combustor is more likely to operate at a higher efficiency than a non-cat stove putting all user error and other external factors aside.
MountainStoveGuy
Minister of Fire
higer efficiency because they can be turned down more? or because the grams per hours are less. i think non cats emit less grams per hour on average then cats. and i relate grams per hour as a good measure of burn efficiency. thats not throwing in material efficiency or anything, just strait burn efficiency. Now cats can burn slower makeing more efficient use of your wood. So what efficiency are we talking about here?
Corie
Minister of Fire
Emissions are related to efficiency, but they are not the same thing. My thermodynamic based definition of efficiency is the percentage of stored heat energy in the wood that the stove converts to heat transferred to your house.
Burning slower doesn't necessarily mean more efficient and neither does grams per hour because lots of factors outside of efficiency, such as firebox size, method of operation, type of wood, etc effect burn times. The efficiency of a woodstove, in my mind (I don't know if this is how they do it in industry), is the amount of potential heat stored in the load of wood divided by the heat transfered to the room.
In numerical terms:
Suppose each pound of wood you load has 6,000 Btu's of energy stored in it. If you had a stove that operated at 100% efficiency, all 6000 Btu's would be released into the room. Obviously that isn't the case; but you get the idea.
Say a stove, like a Quadrafire 3100 operates at a claimed 78% efficiency on a medium to low burn. That means, if you throw 10 lbs of wood in the stove and let it burn to ash, you would expect 46800 Btu to be transferred to your room.
Of course that's a pretty big simplification of the whole situation that occurs, but you see what I mean.
At least that's how I take it, and I assume that's the way they do as well.
Burning slower doesn't necessarily mean more efficient and neither does grams per hour because lots of factors outside of efficiency, such as firebox size, method of operation, type of wood, etc effect burn times. The efficiency of a woodstove, in my mind (I don't know if this is how they do it in industry), is the amount of potential heat stored in the load of wood divided by the heat transfered to the room.
In numerical terms:
Suppose each pound of wood you load has 6,000 Btu's of energy stored in it. If you had a stove that operated at 100% efficiency, all 6000 Btu's would be released into the room. Obviously that isn't the case; but you get the idea.
Say a stove, like a Quadrafire 3100 operates at a claimed 78% efficiency on a medium to low burn. That means, if you throw 10 lbs of wood in the stove and let it burn to ash, you would expect 46800 Btu to be transferred to your room.
Of course that's a pretty big simplification of the whole situation that occurs, but you see what I mean.
At least that's how I take it, and I assume that's the way they do as well.
Shane
Minister of Fire
I think the grams per hour has more to do with stoves overall design. VC Defiant Catalytic .80 grams per hour. VC Encore 1.6 grams per hour. Quad 3100 step top 1.26 grams per hour. Really it seems to be on a per model basis and all are fairly competitive. In general I believe stoves should be their overall efficiency and in that case catalytic wins in tested efficiencies. Of course tested efficiency is only part of the puzzle, MSG reminds us of a good point in that the non-cat stoves in real world situations are probably more efficient due to less user error. And at the end of the day that's what counts right? Also what about replacement part efficiency? Whether your like Elk and can make a combustor last eons with good maintenance habits or your like alot of my customers and burn up cats every other year the fact is they still eventually need replaced. That has to be considered into the economic efficiency of the stove. There are a million different ways to slice this pie.
MountainStoveGuy
Minister of Fire
Agreed shane, which is why i was so happy to open this can of worms. you can look at this equation any way you like. We need some excitment.
Corie
Minister of Fire
Oh absolutely. I was talking about efficiency purely from the scientific point of view with no user error or other factors considered.
of course there are about 90 different other things that will have an effect on the efficiency of the stove. Just like a car is rated from the factory at 28 mpg doesn't mean every soul gets that fuel economy.
That said, I am like elk and with a cat stove I'm a wood efficient fool! But believe me, I know as well as anyone that there are more than two sides to this argument.
of course there are about 90 different other things that will have an effect on the efficiency of the stove. Just like a car is rated from the factory at 28 mpg doesn't mean every soul gets that fuel economy.
That said, I am like elk and with a cat stove I'm a wood efficient fool! But believe me, I know as well as anyone that there are more than two sides to this argument.
wg_bent
Minister of Fire
Hold on guys. I understand the desire to get techie here, but the poster asked a question akin to "Does a Honda mini-van get better gas milage than a Hummer." Both carry 8 passengers....
Any way so much for metaphores...
If the Fireplace is designed as a combustion air limiting appliance then they are close, but the stove will have the edge. These guys are wrestling over numbers like 72% efficiency vs 78 % efficiency. Which in the real world makes no difference. It the fireplace is an open hearth with the fire open to the room with nothing but a spark screen, then the woodstove wins hands down. A great comparison to look at is the efficiency of a Vermont Castings 500 working in doors closed mode vs doors open mode. Seems to me that would answer a lot of questions.
The other wrinkle here would be the type of fireplace. A Russian fireplace (which is a masonry heater) gets as high as 90% efficiency. (I believe that's heat transfer efficiency) So the type of fireplace your comparing is important. I put a Wood stove insert that is roughly mid size into a Majestic open fireplace, so I do have a direct comparison. The fireplace would get my livingroom warm. But the kitchen and hall and bedrooms would freeze, plus I'd go through a large wheelbarrel of wood in 2 hours. NOw with the Stove, the entire house is warm, and the wheelbarrel of wood lasts a day or more.
Any way so much for metaphores...
If the Fireplace is designed as a combustion air limiting appliance then they are close, but the stove will have the edge. These guys are wrestling over numbers like 72% efficiency vs 78 % efficiency. Which in the real world makes no difference. It the fireplace is an open hearth with the fire open to the room with nothing but a spark screen, then the woodstove wins hands down. A great comparison to look at is the efficiency of a Vermont Castings 500 working in doors closed mode vs doors open mode. Seems to me that would answer a lot of questions.
The other wrinkle here would be the type of fireplace. A Russian fireplace (which is a masonry heater) gets as high as 90% efficiency. (I believe that's heat transfer efficiency) So the type of fireplace your comparing is important. I put a Wood stove insert that is roughly mid size into a Majestic open fireplace, so I do have a direct comparison. The fireplace would get my livingroom warm. But the kitchen and hall and bedrooms would freeze, plus I'd go through a large wheelbarrel of wood in 2 hours. NOw with the Stove, the entire house is warm, and the wheelbarrel of wood lasts a day or more.
MountainStoveGuy
Minister of Fire
Yep, agreed warren, i think we intentionaly hijacked this thread because the poster never came back to see us. It was all speculation from the start.
wg_bent
Minister of Fire
MountainStoveGuy said:
Yeah, makes ya wonder if they're serious or not.
o.k. now back to the fun...hijack away.
Todd
Minister of Fire
I don't believe all those manufactures numbers of efficiency and grams per hr. Who knows for sure how they came up with them? EPA or independent cordwood testing? It's all too confusing. Someone needs to do a side by side real world test to find out the real winner. The results of my real world test at my house found the cat stove the winner. But then opinions are like you know what. Everyones has one.
Corie
Minister of Fire
Exactly.
THe only way accurate number could ever be replicated is to test all the stoves on the same day, same wood, same temp, same baro pressure, same everything.
OR
Write a program that compensates for the differences and makes an adjustment. Either way, there are STILL variables that are out of the tests control.
THe only way accurate number could ever be replicated is to test all the stoves on the same day, same wood, same temp, same baro pressure, same everything.
OR
Write a program that compensates for the differences and makes an adjustment. Either way, there are STILL variables that are out of the tests control.
Shane
Minister of Fire
The EPA numbers you can count on. The efficiency numbers are close too. Combustion Efficiency=energy produced during combustion/amount of energy available before combustion. Heat Transfer Efficiency=percentage of heat generated by combustion actually transferred to the room. Overall efficiency=useful energy output/fuel energy input. I don't see how they can really fudge those numbers. The burn times are a matter of interpretation.
Dylan said:
as usual right most of the time does not mean one wins arguement with the other half
wg_bent
Minister of Fire
Dylan said:
If a man is out in the forest and says something without his wife there to hear it...Is he still wrong?
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