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Was just wondering what some of you guys thought about a new wood burning furnace i bought. I replaced a 50% efficiant fuel oil stove with a high effic propane furnace and an add on wood burner. The woodburner has blowers and what not that circulate the air through the house, like a regular furnace. My question is if it might not be better for me to just use propane. Here is what im wodering.
I’ve insulated the attics from r-0 to r-50. I will blow the walls this summer when we do the siding, and replace windows in 5-8 years (triple track storms right now) Now i think that a clean burning wood stove might be on par with a 50% effic fuel oil furnace in a house with no insulation, but i wonder about the amount of crap a wood stove puts out. The woodstove manual says it burns cleanest when its burning hot, but the stove came with a thermostatically controlled damper that kills the air to the fire box (well cuts back) so i would think that at that point it wouldn’t be burning very well. Does anybody have an idea about how woodstoves compare with other kinds of heat for enviro concerns? I have lots of wood for free as i am a carpenter with a pension to pick up logs. I guess one should factor in the energy required to cut, split stack and stoke a woodstove, compared to the energy to drill, refine, and deliever propane. Is it all just a small drop in the bucket compared to the coal burning power plant in town? Well they do have good scrubbers now. I’ve asked at mother earth news before, but i wanted your guys opinions. Thanks in advance.
Kelvin
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Kelvin, man that's like misspelling my name. I have used wood as main/auxillary heat for maybe 25 yrs. Even filter some coal in there. Cast iron, pot belly, Fisher, but 10 yrs ago installed a finnish masonry heater in our new house. Out of em all, the masonry heater is by far the most efficient and the least work. Wood consumption for the same amount of heat is minimal and the pollutants produced so much less that I would recommend it as an alternate heat source more friendly to the environment. Quick hot fire using small stuff, size of your wrist that I glean outta the woods from what falls. Clean flue due to the temp of the burn, the same with the smoke. No catalytic converter needed. Considering that you need not be a environmental pcycho but every little bit helps, you do what you can do to benefit yourself and those around you.
Think globally, act locally.
*My stove makes 3 grams of particulate an hour when all things are working optimally. I think wood burning is fine if you have a catalytic converter and burn a hot fire with dry wood. All of the carbon in the wood that is released with the burning is no more then would be released to the enviroment when the wood rots and ferments (supposedly).Frank
*Kevin -Masonry heaters, first of all, are high mass/intermittent firing heat storage devices.Burn time is usually about an hour each time - perhaps twice a day.Although their particulate and carbon monoxide emissions are just a fraction of what conventional wood stoves put out, comparing these outputs to conventional stoves is like comparing apples and oranges since masonry heater emissions are per "incident" rather then at a rate, so to speak, as it is with conventional stoves that continues to burn for long periods, sometimes all day long, to produce heat, and needs to be fed.Also, it is not uncommon to incorporate outside fresh air supply as part of the stove's construction, which according to some definition of masonry stoves would be structure that is at least 800 kg, or 1764 lbs. In addition to being environmentally friendly, this would be a good thing for the occupants of the house.Scrap that woodstove and use it to make parts for your masonry heater structure.There was an excellent "how to" article in FH several years ago, and recently there was an article on a type of heater that is sort of a variation that has the flue gasses passing under the floor.
*When you burn fossil fuels, you're releasing into the atmosphere carbon (in the form of CO2) that's been geologically bound up for millions of years. This additional CO2 load is said to be a cause of global warming. When you burn wood, you're releasing into the atmosphere carbon (CO2 again) that's been bound up in a tree for probably less than a human lifespan. Much smaller effect on global warming, particularly when you consider what would happen to that tree if it died and fell to the ground on its own. It would rot, and the microbes that digest its cellulose would release exactly as much CO2 into the atmosphere as you would do by burning the wood. Perhaps this rotting would take 10 years, but in the big picture, I think the environmental effects of burning wood and allowing it to rot are similar. Of course, this is global thinking, and your closest neighbor might have a different take on the situation.Andy
*"And that's the big picture, folks."Whoops, Kelvin, not Kevin.Sorry.Anyway, particulate emissions would be of concern if they were spewing out of a chimney in concentrated doses from a fireplace or even a very efficient stove.A masonry heater would be a more responsible option in a populated area.I'm not sure if Colonial Williamsburg area still becomes hazy during heating season from all the wood burning.I think that was the case about a dozen years ago.
*Depends where you are. If you are in town or a moderately to densly populated area don't even think about wood. If you are in Northern Alberta or the Yukon or maybe parts of Montana go for it.Not only is the wood pollution in populated areas irritating to the neighbors but the total concentration is too much for our mother planet to clean up.
*Hi, Fred -Don't you think a properly built and functioning masonry heater will be a benign presence even in a densly populated area ?
*Here is a joke that has a "firewood" theme I received the other day..... Subject: F B I The phone rings at FBI headquarters. "Hello?" "Hello, is this the FBI?" "Yes. What do you want?" "I'm calling to report my neighbor Walter Thibodeaux! He is hiding marijuana inside his firewood." "Thank you very much for the call, sir." The next day, the FBI agents descend on Thibodeaux's house. They search the shed where the firewood is kept. Using axes, they bust open every piece of wood, but find no marijuana. They swear at Thibodeaux and leave. The phone rings at Thibodeaux's house. "Hey, Walter! Did the FBI come?" "Yeah!" "Did they chop your firewood?" "Yep."
*That's great Alan, I'm calling and turning myself in. Thanks
*Easiest way to do the least harm to the planet is to not procreate!If it's too late...No biggy...Everything is cycling forever in the big picture..or not.near the stream,aj
*I agree with Andy on the CO2 and with Alan and Fred on particulates.Creosote is a fairly nasty mix of chemicals including carcinogenic polyaromatic hydrocarbons (PAH's). Fortunately the stuff is not very volatile and mostly deposits inside your chimney. Or better yet, is burned in a catalytically equipped stove. Burning natural gas or propane wouldn't produce the nasty heavy weight stuff. Burning oil would produce some.And what about cutting the wood? That 2-stroke chainsaw and wood splitter are emitting a lot of unburned hydrocarbons. And right in your face, not 20 feet up in the air and diluted before it gets to your neighbor. The newer chainsaws are better, but nothing like a Honda Civic. I also don't know of anyone who got 20 stitches from turning up the thermostat to the gas furnace. But my Mom's leg, co-worker George's face, etc. . .
*I may be oversold on the masonry heater but it could accept lesser quality wood (that would not be considered for a conventional stove due to creosote) and scraps withtout producing the pollutants.Even creosote would be combusted due to the high temperature produced in the seconday burn chambers.I picture feeding it two wooden pallets per day....that I can grab for free around town. Not a practical example, I must admit.I requested a report from a university professor who came up with a proposal for methods of measuring combustion exhaust from masonry stoves.What I should do is search for reports on actual measurements.
*Burning pallets, 2 thoughts:1. Your ash will be 90% nails (experience), so empty ash bin 10 times more often;2. Some pallets may have vinyl coated (or even galvanized) nails which will offend purist environmentalists, you may want to be selective on pallets burned;3. Have read of, but not seen first hand, damage to cast iron due to ash flux reaction of nails and cast iron. Someone else may be able to comment on that.
*Hi, Art -Yes, I wondered about the nails and staples and thanks for pointing out the concern with coated nails (and staples).That's very interesting about damage to cast iron but this may not a problem in a masonry structure with perhaps a metal gate and some other control devices - I've seen stainless hardware incorporated. Servicing a masonry heater would not be something anybody would want to deal with after it is "built".As for the amount of ash and nail contents, was this in a masonry heater ?Due the infrequent firing of only a fixed load per day, this may not be a headache in a masonry heater.I can see a pile of nails accumulating fairly quickly in a conventional wood stove or a fireplace.The university in our town has a forest products research center that tests pallets and their designs so we do come across a wide range of them.
*My brother-in-law, who is a petroleum fuel researcher, says that there is approximately a 20 percent energy loss just in the "cracking" process of the crude oil at the refinery. In other words, it takes the energy of about a quart of fuel to get gallon of petroleum distillates. So it seems to me that wood is a more efficient energy source than fuel oil overall.
*Nick -I guess that's the price we have to pay for convenience....and that fuel/oil mix hungry chainsaw is real handy to have when needed.Maybe a huge price in many other ways.I'm wondering if they have to go through some sort of process to produce natural gas ?Most of us think the stuff just comes out of the ground and it's contained in tanks, ready to burn.
*Alan:I burn about 10 cords a year (1/2 split alder, 1/2 pallets - 50% oak, 50% fir or other) in a 6 foot triangular masonry "fireplace" (1 pallet at a time). This results in about 25ea 5 gal buckets of 90% nail, 10% ash per year. I use the ash/nail mixture as fertilizer for a small christmas tree lot, as the fir trees love iron in the soil. "Fireplace" has circulating water wall heat exchanger (and heat exchanger in chimney) going to both water and forced air distribution and have a forced air draft fan to cut down on smoke during startup or new fuel load.
*Hi, Art -Thanks for the reply.Yikes - that's a lot of nails and it's great that they can help amend the soil for the fir trees.RE- has circulating water wall heat exchanger (and heat exchanger in chimney).What type and size tubing did you use for this ?I've been looking into incorporating water tubing in the secondary burn chambers but not sure if stainless steel will handle the high temperature.And I do like the forced air draft fan idea.
*Alan: regarding SS water tubing in the firebox: It's not the temperature you need to worry about (it's got water on the inside, right?), but the very reactive, transient species in combustion gases. You get wierd, high-energy radicals that are intermediate products of combustion. The answer is SS works fine, at least the right grade. I've installed dozens of SS heat exchangers in cast-iron wood stoves, right in the main firebox. They were 1" nominal size, 3 to 6' bent into a U or doubled J and threaded 1" continuous thread on the ends. (Being in the firebox dictated pretty hefty pipe so it could hits from chunks of woods being tossed in. Further up the chimney, I'd use 1/2".) A nut and washer inside and out with some stove putty sealed them up. Thick black iron would work, but with a corossion rate that need to be factored in. Cast iron is fine, but how do you find small diameter c.i. anymore, since it's not the 1800's? -David
*The question I was asked is: "Don't you think a properly built and functioning masonry heater will be a benign presence even in a densly populated area ?"First of all I don't think anything that affects the environment either postively or negatively is benign. Certainly the flue gas and particulate emission from any wood stove is going to have a negative effect on the environment. The only question is how severe the effect is going to be.It is fairly well accepted that the earth has the ability to clean up after us to an extent. That is why I commented that a wood stove in a sparsely populated area would have a relatively small negative effect. I say relatively because lots of animals, including me, can smell a wood stove for a long way downwind. But, it would be within the maximum level that the earth could clean up.But, when there are a lot of pollution sources, even if they all are very, very low pollution they add up into a total amount of pollution that the earth cannot clean up. So, even if your stove is very, very clean when added together with the other polllution sources in that area the earth self-cleanup level is reached or exceeded. The result is the stuff you see around you in most any metro area.The only sensible answer for folks who live in densely populated areas is to use the least amount possible of the cleanest fuel available..
*Your points are well taken, Fred.I sure hope nobody will notice when I get to operate my own masonry heater.
*Alan, more on pipe. Confirm everything Dave said.Most of my piping is black iron, mix of 1/2" to 2" dia, about 60 feet total in firebox. I usually can come by used black iron pipe 10 cents/# or free, so went that way, but have replaced the pipe that gets heavy ash exposure about every 15 years on average. Finally did put SS in the area where pipe is usually in ash. 2" dia finned sch 40 pipe above fire has lasted 25 years, but 4X4 fins are about 40% corroded away. Also found that the forced draft fan was essential (at least in my case) for getting near complete combustion and avoiding visible smoke and addressing Fred's points, especially when adding fuel.
*Fred , your view sounds like, "hey every body else is so why not me". Maybe that was not your intention but that is what it sounds like. Alternatives to the main stay must be explored and refined to best suit the earth. Don't you think?
*Well Ron Rosa I don't know where you got that interpretation from my posts. I've reread them and I don't see it. Also, your last sentence is somewhat cryptic. So, explain and expand please.
*Oh my God....Lets all group hug the friggin Earth...Near the stream in hug mode,aj
*He he...just April Foolin with Mother Nature and yaa all yesterday...near the sparklling clean stream,aj
*AJ:What was the old ad jingle? "It's not nice to fool Mother Nature?"
*Ron Rosa = Rant Run?I don't mind the ranting. Heaven knows we've had enough of that in the past: But running? Come on guy, don't leave me and everybody else hanging.
*I grew up on a farm and we had a wood burner in the basement that more than heated the house. There were plenty of dead trees on the farm to cut down for firewood. No one ever got hurt with the chainsaw (we paid attention and used the saw with respect and with safety in mind). As for the smell or pollution in a city, I really enjoy when one of my neighbors fires up their fireplace. I think the smell of wood burning is more pleasant than car exhaust, etc.
*I know people who've been very happy with their masonry wood stoves. I love the idea personnally, and if I heated with wood, I'd do the same. It'a as clean, and easy, as you can get with wood.If I was building new, and looking for a "green" house...Geothermal heat pump man. You don't have to burn ANYTHING to heat your house (well maybe a little to get the electricity to run the pumps, some diesl to excavate for the piping, some smelting for the copper,....)
*It is wise to include all costs when comparing types:Oil/Gas - energy loss during refinement (maybe just transportation for gas...)Wood - energy gain during cutting (you), or loss (chain saw, splitter, that totally clapped out '69 Ford truck the wood delivery guy drives that smokes worse than any fireplace).Wood - How many homes could be heated in a year if each one uses 1 to 6 cords per year, and there are about a billion homes already in the US... I guess all of them, for a few years. Then after the trees are gone we could go back to oil or something.As in so many things, moderation. Wood alternative heating is a great idea as long as its not the main stream (those hybrid vehicles take so much more to build because they've got two drivetrains and tons of batteries on board - looks good as long as you only provide 0.5% of the population with one but don't add up if everyone was to have one!).Still, individual thinking is what made this place so great, isn't it? Its the group think that bothers me (California, "Let's make everyone use this one thing! Because it is a law we know it will work out!").
*I would think a bit about the effect nowadays of cutting down dead trees on the ecosystem, such as it is, when assessing the environmental impact of burning wood. A dead tree is not 'waste', waiting to go into your fireplace. You only need to look at all the life that is generated by leaving the tree to decay naturally to understand this. Woodlots are disappearing and fireplaces are growing exponentially. If you think that life is good, think about the impact of harvesting that dead tree relative to other energy sources and emphasizing conservation.
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Was just wondering what some of you guys thought about a new wood burning furnace i bought. I replaced a 50% efficiant fuel oil stove with a high effic propane furnace and an add on wood burner. The woodburner has blowers and what not that circulate the air through the house, like a regular furnace. My question is if it might not be better for me to just use propane. Here is what im wodering.
I've insulated the attics from r-0 to r-50. I will blow the walls this summer when we do the siding, and replace windows in 5-8 years (triple track storms right now) Now i think that a clean burning wood stove might be on par with a 50% effic fuel oil furnace in a house with no insulation, but i wonder about the amount of crap a wood stove puts out. The woodstove manual says it burns cleanest when its burning hot, but the stove came with a thermostatically controlled damper that kills the air to the fire box (well cuts back) so i would think that at that point it wouldn't be burning very well. Does anybody have an idea about how woodstoves compare with other kinds of heat for enviro concerns? I have lots of wood for free as i am a carpenter with a pension to pick up logs. I guess one should factor in the energy required to cut, split stack and stoke a woodstove, compared to the energy to drill, refine, and deliever propane. Is it all just a small drop in the bucket compared to the coal burning power plant in town? Well they do have good scrubbers now. I've asked at mother earth news before, but i wanted your guys opinions. Thanks in advance.
Kelvin