Joined: Sep 14, 2004 Posts: 6468 Location: Rural Virginia
Posted: Wed Apr 11, 2007 8:13 pm Post subject: Re: Wood as an auxiliary energy source
Commanding_Heights wrote:
Heineken wrote:
No one has mentioned the labor (and time) involved in heating one's place entirely with wood.
As someone who heats entirely with wood, I can tell you that this is a huge oversight.
Also, Gideon is right: There is an inverse relationship between how fast wood grows and how much heat energy it supplies. That is because the slower wood grows, the denser it is, and vice versa. "Fast-growing" methods (like coppicing) aren't a magic bullet.
Wood can play an energy role in a future world, but it will be a radically different world with far fewer people.
Do you have any links/docs that dismiss coppicing as a "magic bullet"? I'm truly not trying to be a smart ass, I'd really like to read some opposing view points. My understanding is that even though the density of the wood might not be as much and the btu's not as high, the enormous growth rate more that compensates for that. I even tried a coppice experiment with a 1/4 acre wooded lot I own that has mainly poplar. (I know, I know not the best wood for heat but it is a fast grower) I was able to cut more than enough coppiced wood with some to boot in a 3 year time span.
I've also heard of people chopping the coppiced wood into bits and getting a larger return (over the long term) from wood stoves due to increased mass and less space for oxygen. Kinda like coals putting off heat for days. I know the heat wouldn't be as hot but it does make sense that maybe the wood would burn/smolder longer.
But like I said this is just something I've read/heard here and there and have no proof.
When you refer to labor involved are you referring to cutting, hauling, stacking or loading the stove. I'm guessing all of the above.
Not to beat a dead horse but coppiced woods are once again much easier to deal with in this sense because you're not dealing with trees weighing tons that require chain saws, and lots of feul for hauling. They also take a lot less time to dry.
I'm not trying to bash coppicing. For some situations I can see how it would make sense, such as, perhaps, for people with a lot of open land and relatively few trees. No, I don't have any links, just my own experience with wood and wood-burning.
Cutting coppiced wood still requires a chainsaw unless you have a very short winter (like maybe two days long).
I don't agree that methods (or species) that promote fast growth compensate for the low-density wood that results. Low-density wood tends not to form coals, which is crucial to making a hot, long-burning, clean fire. What you tend to end up with with low-density wood is a lot of smoky fluff and a fire that needs constant tending and refueling. Not to mention less heat. I'd think that chopping coppiced wood (or any wood) into tiny bits and trying to burn the result would make the problem even worse unless the stove is equipped to handle that (like a pellet stove).
Yes, the labor involves all of those things plus splitting (a biggie), cleaning out the ashes and disposing of them (I put them in my garden), chainsaw maintenance, and periodically cleaning the stovepipe (I do it just annually, but some authorities recommend more frequent cleanings). I also have to dismantle my catalytic combuster and clean it, along with the area where the pipe enters the stove, which collects creosote particles. (I hate the catalytic combuster, but I'm stuck with it for now since I have a 1980s-era Englander.)
Oh, and don't forget collecting (or making) kindling. Very important.
And then all the work in keeping the fire running just right. Many adjustments during the day, and many trips to the woodshed over the course of a week.
So between the labor items you listed and the ones I added, labor is a huge component of wood heating. I don't mind the work, and I'm used to it. But it's there, a big fat reality of this way of life.
I use mostly white oak, taken from thinning cuts to improve my stand. It's a wonderful wood. I'd burn hickory (which is even better), but I don't have much hickory and I'm trying to encourage its reestablishment on my land.
Joined: Apr 28, 2005 Posts: 3647 Location: West shore Lake Eire, MI, USA
Posted: Thu Apr 12, 2007 4:40 am Post subject: Re: Wood as an auxiliary energy source
Speaking of Cottonwood and Pine we had a special name for those when I was growing up, Gopher Wood. Why? Because as soon as you got the fire stoked you had to Go-For-Wood because it would be ashes by the time you returned.
This thread drums up some strange memories _________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
Posted: Thu Apr 12, 2007 6:01 am Post subject: Re: Wood as an auxiliary energy source
Growing, cutting and seasoning your own wood certainly requires a large lot and lots of labor. I think we can develop systems that are more convenient for the user, and more adapted to city life.
Wood burning district heating is a possibility. In Sweden (and Finland I believe) it is very common for cities and neighborhoods to have district heating plants that heat water for tap water and radiators. In fact, district heating systems were used already in the happy cheap oil days, and were rather easily converted to burning renewable fuels. Most of them do these days.
A more modern development is cogeneration of electricity and heat, using biomass. You get electricity and heat. Such plants must be large, though, and are not yet common.
I am also surprised that noone so far has mentioned wood pellets. Many homeowners in Sweden that are not connected to a district heating system now replace their oil furnaces with wood pellet furnaces.
Wood pellets have some drawbacks compared to oil. You need three times as much by volume (bigger storage place or more frequent deliveries) and some weekly emptying of ashes. 15-20 minutes work per week is what I read about. You set it up with an automatic feeding system to the furnace - that is why it requires so little work. The advantage today is the price - a lot less expensive than heating oil.
Not everyone might be familiar with wood pellets: They are industrially made from scrap wood, ground up and very dry, and then compressed into standard sizes, shaped like cigarette butts but about twice as big. Wood pellets burn very cleanly, with little smoke and pollution.
Of course district heating with wood and wood pellet furnaces in individual homes require more transport than growing your own wood around your house. In a totally oil free world - can we imagine wood-fuelled steam ships on inland waterways? Sailing ships with wood on larger bodies of water? (In fact, wood transporting sailing ships was the last commercial use of sails to disappear in Scandinavia, a viable business well into the 20th century.) Can we imagine ponies pulling carts on rails from the ships to the heating plants? Slow speeds and rather light loads need quite simple rails to increase efficiency and can be drawn right through neighborhoods, since there are little risk of serious accidents and noise. (Wasn't rail transport started with ponies pulling coal, by the way?) Can we imagine homeowners transporting their weekly load of pellets by bicycle trailer a few kilometers from the pony transport? Teenagers having their pellet routes (like a newspaper route except scheduled differently) for pellet distribution to homeowners who rather pay for the transport of their pellets?
A very nice thing about wood, wood pellets and such, is that it is not poisonous - a spilled load is no environmental hazard, and you need no specialized containers to transport it safely.
Posted: Thu Apr 12, 2007 9:45 am Post subject: Re: Wood as an auxiliary energy source
Well, if you own a wood lot and just have to contribute your labor, traditional wood is probably the way to go. Especially if you like the job.
The major premise was a city situation.
Cost going up with demand? Well since wood pellets are made from renewable material, old Adam Smith economy would say that supply soon should start to increase, when the producers discover this is a good way to make money.
In what ways are wood pellets loud? I have never heard this before. (Almost ten years ago when we had to change our heating system, I wanted wood pellets. Hubby thought the techniqe and the feeding thing looked very primitive and unreliable, so we installed a ground heat pump. Constantly dependent on electricity, which I think is the major drawback with heat pumps. It has worked fine, though. So I have no personal experience of wood pellets, but I know they are used more and more here. As are heat pumps)
Posted: Fri Apr 13, 2007 2:24 am Post subject: Re: Wood as an auxiliary energy source
OK Gideon then I understand. You are relieved of the (sort of enjoyable) task of putting in fresh wood, but instead get mechanical noise. The reason this issue has not surfaced in Sweden probably is that the typical situation here is an oil furnace in the basement being replaced by a wood furnace in the same place. Basements like this are usually used for furnace, general storage, perhaps a laundry room, possible a garage. A bit more noise from the furnace is not a problem.
Joined: Aug 26, 2005 Posts: 428 Location: Windy City No Longer
Posted: Fri Apr 13, 2007 8:22 am Post subject: Re: Wood as an auxiliary energy source
Gideon raises an interesting point about location. Around here most people seem to have their wood burners outside. This could be because Michiganders just love going outside at the height of winter to toss logs/pellet bags around or for some other reason.
My understanding was that the insurance companies loathe wood burners and so most systems have been outdoor installs since the last energy crisis (late 70's). I've seen several outdoor pellet burner systems around here. The hopper for the pellets looks huge.
Placing one outside probably doesn't do too much to the overall energy efficiency since you'll need a pump indoors or out. Of course, this assumes your water line is relatively well insulated, unlike mine. _________________ TANSTAAFL
Posted: Fri Apr 13, 2007 2:39 pm Post subject: Re: Wood as an auxiliary energy source
Outdoor boilers are horrible polluters; typically just a big fire box surrounded by water. They burn very inefficiently and use lots of wood. We installed a Tarm wood-gasification boiler with 600 gal. storage tank so it's always burning hot. Upside: easy to tie into existing hot water baseboard. Downside: expensive but that's about it. The simplest system is a smaller well-insulated house with wood stove. Outlying rooms get colder.
Deforestation was a major issue in Europe and New England before coal came onto the scene. That was, what, 250 years ago? Given population increase and lifestyle expectations, wood won't help much for the masses. I expect to have to defend our woodlot with force.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
News
Discussions
Resources
Members
Forum FAQ
Search
Usergroups
Profile
Log in to check your private messages
Log in
