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Can burning trees replace burning coal?

  1. Apr 1, 2007 #1

    ShawnD

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    This is in no way a suggestion; I'm just curious. Please read on.


    A friend of mine has a house that is heated by burning wood. I won't give his entire story, but he did include that burning wood for heat is significantly cheaper than burning natural gas, which makes it way way cheaper than electric heating (electric is the most expensive). This would imply that there is either a huge surplus of trees in North America, or there is a shortage of coal (not bloody likely).
    Anyway, could burning trees actually be used to generate heat and power on a large scale? I don't mean power the entire country the way coal does, but what about small towns or areas that are somewhat isolated from other sources of energy?

    Thoughts?
     
  2. jcsd
  3. Apr 1, 2007 #2
    We have a stove in our house that can heat using either coal or wood. If you want to save money on heat you can save a bunch by just heading down to a coal mine, buying a truckload of it bulk and burning it in the stove, same with the trees. One winter we pretty much just burned coal in it and was much cheaper. The coal puts out a much nicer heat than the wood but it does have a distinctive smell and you don't get the nice crackling sound :(

    I don't think using trees to heat entire small towns or other isolated areas would be a terribly good idea. A lot of towns wouldnt have a big enough supply nearby and it would be a terrible idea to cut down what little they have, so then you are stuck with hauling a whole crap load of trees in from somewhere else. You would have to pay for the logs, then pay for someone to bring it in, then make sure you have enough to last you a long time because it would definitely be bad if you became reliant on it and then ran out. That being said, you are right on a small scale some people can make it work so who knows.
     
  4. Apr 1, 2007 #3

    Integral

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    We have a lot of people heating with wood in some areas of Oregon. The trouble is the smoke, we also have some bad pollution problems due to wood smoke. If wood is used it must be burned clean, you cannot let it smolder, as many stoves do.
     
  5. Apr 1, 2007 #4

    ShawnD

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    I guess this and scorpa's answer pretty much sum it up. scorpa, does coal burn cleaner than wood?
     
  6. Apr 2, 2007 #5

    Chi Meson

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    I can't imagine that an open fireplace can possibly heat more cheaply than other standard choices. In many cases, a fire in a fireplace can suck out m ore heat than it gives. A good woodstove makes all the difference in both efficiency and clean-burning of wood.
     
  7. Apr 2, 2007 #6
    Not really sure, all I know is it does burn a longer and puts out a much warmer heat. When we have the coal stove going even when it is 40 below outside it gets quite hot upstairs.
     
  8. Apr 2, 2007 #7

    Chi Meson

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    Processed coal (called coke) is much cleaner than wood, and it has more energy per unit of weight. Not as available as trees though. I'd hate to see New England returned to the state it was in 100 years ago. Essentially, there were no trees left. With the exception of upper Maine.

    I don't think we can replace coal with wood, except as point-source (in your own home) heating.

    Can I plug my wood stove manufacturer? I've got an Aladin "Quadrafire" stove; it burns as efficiently as a catalitic model, but without the problematic catalitic converter. Glass window gives a nice fireplace appeal, and you can actually watch the upper burn zone where the exhaust gasses are re-burned with heated air. Another advantage is that you can burn junk wood, pitchy wood, scrub wood, whatever you got. When the thing is burning hot, you can toss in a wet, rotting log and that will burn too.

    I went off topic, didn't I? Sorry.
     
  9. Apr 4, 2007 #8

    turbo

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    My wife and I have a very efficient hot-burning wood stove and a small well-insulated log house. It's very easy to overcharge the stove and drive the temperature up to 80F or so, so I'm going to spend extra time with the wood splitter this spring to split the wood into smaller pieces for better control of temperature and burn-time. Using wood as our only source of heat this winter, I think we have burned maybe 3 cords or a little more. We have a 10 acre woodlot that will never run out of wood, though I have been harvesting mostly dead or diseased trees and buying most of our firewood from our niece's husband. He's a nice guy, very honest, and they have little kids to take care of. Plus, running my chain saw all day is less attractive to me than it was 30 years ago. I feel that the environmental impact of our wood-burning is negligible, since we are cleanly burning carbon that is currently part of the biosphere, not carbon that has been sequestered for millions of years.

    Wood is not going to be the answer for everybody due to problems of availability, storage/drying space requirements, and most of all, ignorance. Lots of people are numb enough to burn green wood, resulting in smoldering fires and chimneys plugged with creosote - then we see their pictures in the paper standing outside the ruins of their house. The trick to burning well-seasoned wood is to get at least a year ahead in your wood supply and stay ahead, but again, this requires storage space where the wood can stay under cover (perhaps stacked on pallets, covered with tarps). I have probably 3 cords ready for next winter, and will supplement that with dead, standing trees from my woodlot while this year's load of wood is drying. I will add that if you're going to burn oak, it is mandatory that it be at least a year old. There are valve-like flappers between the cells in an oak tree that close when a cell is damaged and losing pressure. They make it VERY hard to dry oak. When I see a load of oak firewood rolling down the road late in the season, I have to hope that the buyers know what they're doing.

    ShawnD, the surplus of wood in the US is regional. Here in Maine, our main competition for firewood is the paper industry. If a paper mill is paying $120/cord for tree-length hardwood (even poplar), it's going to be tough for a firewood supplier to justify cutting the wood to length, splitting, and delivering it for anything less than $150-175 per cord.
     
  10. Apr 4, 2007 #9
    Here's a lateral thought...

    Premise: It was said that coal burns cleaner than wood.

    Problem: Coal brings "new" carbon into the atmosphere.

    Solution: Burn coal, bury wood.

    :biggrin:
     
  11. Apr 4, 2007 #10

    ShawnD

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    I love it!


    Lots of good information here. Thanks guys :smile:
     
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