Heating with Wood Pellets Case study and Fuel Comparison Savings!!!

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wood chips will burn in a pellet stove, but the rate of combustion is going to be much faster than with pellets, just because of the density. Its probably worth the experiment to see how it all goes, but I'd expect less than stellar results.
 
Moisture content can be a problem. Chips have lots of "wedge like" shapes that the auger will have a problem with. Yes, you can run a small amount though a stove and may get lucky as to not jam the auger. Burn rates differ between the chips and pellets and requires a uniform mix. Is it worth it to burn 1 lb of chips to every 20lbs to 40lbs of pellets and deal with the auger jams? For some maybe. Do you pour in a little of junk gas in your vehicle tank at every fill-up to get an extra 1mpg? Most people don't because it isn't worth it if the bad gas causes a problem.
If one feels up to the task and understands the risk of putting wood chips in a stove and that they are the sole responsible party for any bad things that may happen then have at it. A lot of engineering and testing went into making wood pellets and the price is reasonable so from that point of view using chips is only worth trying as an experiment in a controlled environment.
 
A little math on the wood chips.
1 gallon wood chips tightly packed = 231 cubic inches = .13368 cubic feet
Assuming white oak is 47lbs per cubic_foot
white oak is 8500 btu per pound IF it was dried properly

How many btus are in that 1 gallon of chips? .13368 * 47 *8000 = 50,000 BTUs.......out of the 6 lb container of chips
Ah man, I can't remember where I put my beer.
 
I went down to the shop and measured how much a gallon of my wood shavings from my planer weighed. A moderately packed gallon, as they would be presented to the stove, weighs 0.80 lbs. That's about 6400 btu's per gallon. Hardly worth the effort, me thinks. My agreement with arnash was about the lack of any substantiating proof to the negative comments that were made. Got to back up those comments with data! That's why I did all my testing and experimenting with trying to improve the heat transfer efficiency of the stove's tubes. I could have just said 'It sure feels hotter'.........
 
I'm still looking for an explanation of how wood chips will jam an auger. augers are really simple technology. A screw goes around in circles, how does that get jammed by something the size of chips? As if pellets don't come in all sizes due to breakage. As for the amount of heat chips would produce, no doubt it's not a lot but someone who cuts their own wood for a wood stove will have a huge amount of chips and what better use is there for them than to produce heat, and doing it in a pellet stove sure seems like the best way to do that.

I'd sure like to improve the heat transfer efficiency of my stove’s tubes since absent the heavy steel sewer pipes I'm using for part of my vent system, the heat from the vent is just about is as great as the heat from the room blower. That is very inefficient since half the heat is lost to the outdoors. I'd like to discover something better than my 2 small fans blowing on the "tin" lengths of vent pipe to retain more of the heat indoors. Maybe a more powerful room blower would keep more heat from escaping, or washing the heat transfer tubes daily. They should have designed pellet stoves with more of those tubes but maybe 'way back in the early days pellets were dirt cheap. I'll bet they were, before the EPA and Endangered Species Act killed a whole lot of logging in this country, like they did in my county.
 
turbotech said:
A little math on the wood chips.
1 gallon wood chips tightly packed = 231 cubic inches = .13368 cubic feet
Assuming white oak is 47lbs per cubic_foot
white oak is 8500 btu per pound IF it was dried properly

How many btus are in that 1 gallon of chips? .13368 * 47 *8000 = 50,000 BTUs.......out of the 6 lb container of chips
Ah man, I can't remember where I put my beer.

if white oak is 47 lbs/ cubic foot...wouldn't it sink in water?

I do not think wood chips would really jam up in the auger...maybe some really big ones will just wedge themselves into the flights and prevent the other chips from moving freely, but I dont think it would really "hurt" anything.
 
Delta-T said:
turbotech said:
A little math on the wood chips.
1 gallon wood chips tightly packed = 231 cubic inches = .13368 cubic feet
Assuming white oak is 47lbs per cubic_foot
white oak is 8500 btu per pound IF it was dried properly

How many btus are in that 1 gallon of chips? .13368 * 47 *8000 = 50,000 BTUs.......out of the 6 lb container of chips
Ah man, I can't remember where I put my beer.

if white oak is 47 lbs/ cubic foot...wouldn't it sink in water?

I do not think wood chips would really jam up in the auger...maybe some really big ones will just wedge themselves into the flights and prevent the other chips from moving freely, but I dont think it would really "hurt" anything.

Nope, water is more dense.
Yes, maybe jam or maybe not. If it does jam, would it hurt anything?

The thing is a pellet has specs to meet to burn in a stove. We are talking "wood chips" here of unknown size and shape. In other words, no spec to follow. For someone to say it will and will not work really has no meaning because we haven't really defined what a wood chip is. Everyone is right by using there own wood chip definition. Chain saw chips, sawmill chips, 50hp tree chipper chips? It matters. Is it really worth it to burn a few gallons of chain saw chips? Is it worth it to burn mixed in local sawmill pine chips that burn way faster than pellets when mixed in? Jam the auger with tree chipper chips? I guess that is why all of this material is processed into a pellet and not sold as bagged chips.
 
Actually, I did define the type of chips I was wondering about, chainsaw chips, uniform size and shape. I mixed a gallon of such chips into 2-3 gallons of pellets and it's having no effect on the auger. I'll go ahead and burn all the chips I have by mixing them in with the pellets. No problemo. I wonder what would happen if someone mowed their autumn leaves with a mulching mower and mixed them in with their pellets. Of course one would probably not be inspired to do that unless the price/availability of pellets was badly compromised. Hope things don't get that bad, but it would be interesting to know what would happen with such a test.
 

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