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Should Green Homes Burn Wood?

Extracting fossil fuels like coal, natural gas, and oil — by mountaintop removal, fracking, and deep-sea drilling — all entail environmental risks

Posted on Jun 4 2010 by Martin Holladay, GBA Advisor

Environmentalists often argue over the wisdom of heating homes with wood. Strong arguments can be marshaled on both sides of this debate, so I’ll do my best to represent both positions before summing up.

Burning wood makes environmental sense

According to wood-fuel advocates, burning wood is carbon-neutral. While burning wood releases carbon into the atmosphere, the carbon would have been released anyway if the tree had died of old age and rotted on the forest floor.

Here’s how a forest’s carbon cycle works: as trees grow, they sequester atmospheric carbon by converting CO2 in the air to leaves, twigs, and wood. The CO2 isn’t permanently sequestered, however, since virtually all wood (with a few exceptions, like Tutankhamen’s throne) eventually burns or rots. The amount of carbon released by burning is the same as the amount released by rotting.

As long as firewood is sustainably harvested — that is, as long as a logger limits annual cutting to the annual growth of the forest — burning firewood is carbon-neutral.

Wood-stove advocates also point out:

  • It’s better to buy firewood from a local logger than to buy oil or gas from overseas. Spending money locally strengthens the local economy.
  • Since firewood is usually harvested nearby, those who burn wood are less likely than those who burn oil or gas to experience unexpected disruptions in their fuel supply.
  • Wood stove technology is simple and robust. Wood stoves can keep a house warm when electrical service is disrupted — for example, during an ice storm.
  • Wood ashes are a useful soil amendment; they help raise the pH of acid soil and supply potassium, a necessary plant nutrient.
  • The environmental effects of firewood harvesting are more benign than the environmental effects of coal mining or oil and gas drilling.

Burning wood is an environmental disaster

Environmentalists opposed to wood burning often live in congested areas affected by air pollution or in areas where forests are threatened. Seeing trees as precious, they don’t look kindly on logging trucks.

Foes of wood burning point out:

  • In many parts of the world, annual firewood cutting exceeds annual forest growth — so wood burning is not carbon-neutral.
  • Commercial firewood harvesting requires fossil fuel for chainsaws and trucks, undermining the argument for carbon neutrality.
  • If everyone in the U.S. burned wood, the nation’s forests would be decimated.
  • Wood smoke includes many noxious pollutants that contribute to lung disease and cause premature deaths.

Particulates are probably the most dangerous components of wood smoke. Particulates small enough to enter deep into the lungs are known as PM10 particulates (meaning they have a diameter of 10 microns or less); these are the particulates that are most likely to contribute to lung disease. Those most vulnerable to smoke-related health problems are people with asthma, young children, pregnant women, and the elderly. According to one source, each year in the U.S., particulates from all sources (including vehicle exhaust) are responsible for 30,000 premature deaths from lung disease, heart attacks, and stroke.

In addition to particulates, wood smoke includes small but significant amounts of arthracen, benzene, biphynel, carbon monoxide, chrysene, dioxin, fluoranthene, formaldehydeChemical found in many building products; most binders used for manufactured wood products are formaldehyde compounds. Reclassified by the United Nations International Agency for Research on Cancer (IARC) in 2004 as a “known human carcinogen.", naphthalene, nitrogen oxide, phenanthrene, polycyclic aromatic hydrocarbons, pyrelene, pyrene, and sulfur dioxide. Each of these chemicals can negatively affect human health.

Weighing pluses and minuses

Burning wood is almost carbon-neutral. In light of the looming problem of global climate change, carbon neutrality is nothing to sneeze at.

If you harvest firewood with a bow saw and a wheelbarrow, as I did in my early years, wood is as close to carbon-neutral as any fuel. In most cases, though, firewood is harvested with a chainsaw and a truck. According to those who have studied the issue, each BTUBritish thermal unit, the amount of heat required to raise one pound of water (about a pint) one degree Fahrenheit in temperature—about the heat content of one wooden kitchen match. One Btu is equivalent to 0.293 watt-hours or 1,055 joules. of fossil fuel used to harvest firewood yields 25 BTUs of wood fuel — a respectable ratio. In the future, perhaps, loggers will use chainsaws that burn alcohol distilled from sugar cane and drive trucks fueled with biodiesel.

It goes without saying that anyone involved with green building should cut their own wood or buy their firewood from loggers concerned with sustainability. However, I don’t believe we should use a global assessment of forest health to judge the morality of local wood burning. Just because forests are severely threatened in Haiti and Madagascar does not mean that Americans should refrain from harvesting firewood near their homes. In this sense, all forestry is local.

In many northern and southeastern states, the woods are full of unharvested fuel, including standing dead wood, fallen limbs, trees knocked down by ice storms, and stands of dense forest that would benefit from thinning.

The deleterious effects of wood smoke on human health are a serious concern. However, wood smoke is much less likely to cause health problems in sparsely populated rural areas than in densely populated areas.

Newer stoves pollute much less than older stoves. EPA regulations established on July 1, 1988, required stoves to meet stricter limits on particulate emissions. On July 1, 1990, newer Phase II regulations — which require stoves with catalytic converters to emit less than 4.1 grams of particulate matter per hour and stoves without catalytic converters to emit no more than 7.5 grams per hour — took effect.

All fuels have disadvantages. (Read more about fuel choices on GBA’s “Heating Options” page.) If you have an electric heat pumpHeating and cooling system in which specialized refrigerant fluid in a sealed system is alternately evaporated and condensed, changing its state from liquid to vapor by altering its pressure; this phase change allows heat to be transferred into or out of the house. See air-source heat pump and ground-source heat pump., remember that 50% of U.S. electricity is generated by coal-burning power plants. The recent oil spill in the Gulf of Mexico and recent coal-mine disasters (not to mention mountaintop removal) have reminded Americans of the risks associated with oil drilling and coal mining. While flue gases emitted by a gas furnace are far more benign than wood smoke, gas drilling and gas pipelines also have negative environmental effects.

Responsible wood burning

Because of the health problems associated with wood smoke, wood burning is inappropriate in densely populated town and cities. Wood burning is also inappropriate in areas where forests are threatened.

If you live in a rural area and choose to burn wood:

  • Cut your own firewood or buy your fuel from a responsible logger who harvests firewood sustainably.
  • Use a right-sized wood stove. A hot fire in a small stove produces cleaner smoke than a smoldering fire in a large stove.
  • Use an EPA-certified wood stove. Do not use an outdoor wood-fired boiler; these appliances are notoriously smoky and inefficient.
  • Don’t use your stove to burn trash.
  • Cut or buy your wood one year before your burn it, and store it under metal roofing or in a woodshed. Seasoned firewood burns cleaner than green firewood.
  • No matter what kind of fuel you burn, strive to improve your home’s thermal envelope. Plugging your home’s air leaks, improving your home’s insulation, and adding storm windows will save you money and reduce the amount of wood you need to burn. That’s good for your pocketbook and good for the planet.

Last week’s blog: “Housewrap in a Can: Liquid-Applied WRBs”


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  1. Martin Holladay

1.
Fri, 06/04/2010 - 12:05

Every Effort is Important
by Sam Bagwell

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To get the best impact on our energy crisis, every contribution is important. Only by using every possible tool in the arsenal, can we achieve even a marginal assault on energy use. Using fire wood where it makes sense is one such tool and as such, it should employed at every possible opportunity.


2.
Fri, 06/04/2010 - 13:17

Way to ask the hard questions!
by Li Ling Young

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Nice, nuanced summary of the issues, and a great follow-on to the post about potent green house gases in the manufacture of (some) insulation. There are no sacred cows here, nor can we afford such.


3.
Fri, 06/04/2010 - 15:04

wood pellets
by mike

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when we lived in Freiburg, wood pellets were generally considered the greenest option, since they were formed from timber waste and burn efficiently.


4.
Fri, 06/04/2010 - 22:05

freestanding buildings for individuals and nuclear families
by j chesnut

Helpful? -2

I reference this website frequently and appreciate its focus on residential projects. Often posts like this about providing heat through fuel combustion or other posts that discuss the issues of using building materials made from industrial chemicals to achieve greater levels of energy efficiency point to difficult environmental dilemmas that are at a scale beyond what an individual building project can impact in a significant way.
Larger societal questions are likely best outside the scope of this website for the sake of a clear productive focus on advancing our building and design practices. However I'd love to see in addition to the impacts of fuel types and building product alternatives more information about the impacts of living arrangements. While there are more and more interesting examples of energy efficient homes popping up all the time the majority of these buildings apparently serve very few individuals per building.


5.
Sat, 06/05/2010 - 08:41

Upstate NY is in 100% agreement with this article Martin
by aj builder, Upstate NY Zone 6a

Helpful? 1

Great article. I wood like to also mention that the Europeans have developed amazing wood burning units like there top loading down firing wood gasification units. Long burn times without smoldering along with some of the units (chord wood or pellet) have automatic ash handlers.

And yes burning wood should be a choice for some not all. Albuquerque NM and Los Angelos and similar locales have smog entrapping surround moutain terrain... Not a place for wood burning. The Adirondacks with all of our trees and few residents... is perfect for burning wood to use for any and all purposes.

Great article Martin


6.
Sat, 06/05/2010 - 11:52

Response to J. Chesnut
by Martin Holladay, GBA Advisor

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J. Chesnut,
I'm glad you wrote, "I'd love to see (in addition to the impacts of fuel types and building product alternatives) more information about the impacts of living arrangements. While there are more and more interesting examples of energy efficient homes popping up all the time, the majority of these buildings apparently serve very few individuals per building."

An excellent point. While a brand-new $400,000 home may use very little energy, its construction may not make ecological sense. Perhaps if extended families shared living quarters -- even living quarters that weren't particularly efficient -- we'd end up with a lower ecological impact.


7.
Sat, 06/05/2010 - 18:06

burning dry wood vs damp
by Jim Olson

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Good article. One thing I'd add is that most wood has the same btu output by weight not by cord (oak has nearly the same as pine dry pound for dry pound) and water contributes to this weight. The efficiency of wood is based on its moisture content and the dryer the wood the more btu's you'll get out of it. And the hotter the fire the less pollutants


8.
Sun, 06/06/2010 - 11:34

Existing vs. New Construction
by Jan Juran

Helpful? -1

Hi Martin: many thanks for the very informative thoughts. From a practical viewpoint, it may be useful to think about this issue differently in existing vs. new construction. Wood burning in existing construction can be very helpful in cold climate areas such as New England where wood is sustainably available. Lodgepole pine trees on millions of acres in Colorado and Wyoming are dying and will oxidize on the forest floor unless otherwise used, victims of a pine beetle infestation exacerbated by warming global temperatures.
Do you know of any Best Practices guidelines for new construction? We may otherwise be giving back some of the benefits via: leaky chimney dampers; low R value masonry and metal chimneys which penetrate the building envelope (both heating and cooling penalties depending on the season); convective air currents arising from temperature differentials inside large chimneys; metal pipe air intakes which can be quite difficult to insulate, channeling cold into the envelope 24/7 during heating season; backdrafting through leaky woodstove doors; and so forth. Surely we can do better than existing typical practice with wood burning appliances in new construction? Raising net total (not just stove) residence efficiency could in effect significantly expand wood/biomass availability in North America. Better yet, we won't have to split and carry as much wood.


9.
Mon, 06/07/2010 - 05:17

Doing better
by Martin Holladay, GBA Advisor

Helpful? 1

Jan,
You have challenged the engineers at wood stove manufacturing companies and metal chimney manufacturers to do better; I hope they are listening.

Since my grandmother's day (my grandmother grew up with a wood-burning kitchen stove similar to the one that now sits in my kitchen), here's how things have improved:

1. We've gone from unlined brick or stone chimneys to masonry chimneys with linings of clay flue tile or stainless steel (or stainless-steel chimneys without any masonry).

2. We've gone from stoves with leaky doors and seams to airtight stoves.

3. We've gone from stoves that were never tested for particulate emissions to stoves with catalytic converters or better firebox designs to significantly reduce particulate emissions.

4. Some stove manufacturers have developed stove models with outdoor combustion air ducts.

So, technology is improving. I certainly hope the technology continues to evolve. There are now a few very efficient wood boilers that burn firewood at very high temperatures and store the heat in hot water tanks for homes with hydronic heat distribution systems. The downsides to these new wood burners:
-- they cost significantly more than simple wood stoves;
-- they use electricity and therefore don't work during power outages;
-- they require highly trained maintenance personnel to diagnose and fix problems.


10.
Mon, 06/07/2010 - 10:12

PM matter
by Ed Welch

Helpful? 1

Smoke identifies particulate matter, no matter how the EPA regulates wood stoves and fireplaces. And if your neighbor wants to save energy by burning wood, and that smoke drifts into your back yard where your children are playing, it is never a good idea.

Also, inversion layers can hold smoke close to the earth's surface, putting people at risk who live far from the source.

My view is that it is a poor alternative source of energy....somebody is being adversely affected.


11.
Mon, 06/07/2010 - 10:23

Response to Ed
by Martin Holladay, GBA Advisor

Helpful? 1

Ed,
I agree that if you have a close neighbor, burning wood isn't a good idea.

Once you've designed and built a home with passive solar features, and the house is close to airtight and superinsulated, what fuels do you suggest?

I agree that "somebody is being adversely affected" whenever wood is burned. But the same is true whenever anyone uses grid-supplied electricity, or natural gas, or heating oil, or coal.


12.
Mon, 06/07/2010 - 10:55

A smoky issue
by Daniel Ernst

Helpful? 1

Martin - Excellent summary. Good fuel for the fire ;)

A couple of things to mention for those who do choose this option . . .

The beginning phase of a fire is the dirtiest. More particulates are generated during the first few minutes because the chemical reaction is throttled. A) The wood is cold. B) The firebox may be cold. C) Moisture content is highest, since the water is not yet steamed out of the wood.

One way to improve this situation is to use a "top down" technique, where you light your kindling on top of the larger pieces. This creates less smoke, a cleaner start. It is counterintuitive, but it works.

Also, users of cast iron stoves should be careful about closing the damper at night. As you stated, a hot fire burns more cleanly. Choking the air supply creates more smoke. Some people will go through great effort to have a few coals left in the morning - and in doing so they create problems (more smoke, dangerous creosote formation in the chimney). It is best to throttle the night fire AFTER the initial burn period, when the fuel is in the coal phase.

Finally, I wanted to mention another option: the masonry woodstove. They provide the cleanest option for burning wood. The downside is that they are also the most expensive. Masonry woodstoves don't have "dampers." You burn the fire as hot as possible in the shortest time period (>1500 F for 2-3 hours). The masonry absorbs and releases this heat over a 24 - 36 hour period, so you only have to tend the fire 1X or 2X per day. After the fire is out, the chimney can be sealed with a gasketed cap to prevent heat loss and air infiltration. And unlike the high efficiency boilers (that use water to store the heat), the masonry woodstove is completely passive - no electricity is required.
_______________________

If you follow our history, we (humans) started heating with wood. We "progressed" to coal and natural gas, then oil, and more recently nuclear power. Our fuel density has increased exponentially. Over time we moved from a carbohydrate economy to a hydrocarbon economy. If you look at the bigger picture, the lines between our technology and our fuel density are largely parallel. The same holds true with population density and fuel density / consumption.

Yet we don't know how to deal with our oil spills. And we still don't have a safe way to dispose of our highly concentrated nuclear waste.

Down here in the Fayetteville Shale formation there isn't a square mile that doesn't have several natural gas wells planned or drilled. They are fracking the wells with unknown and unregulated chemicals. Local water treatment plants cannot process the effluent from these wells. The gas reserves will be depleted in ~ 30 years. And we don't know the long term consequences.

One of my college professors stated it well. "We're long on knowledge, short on wisdom."

The beauty of firewood is its simplicity, its long history, the fact that it's organic and renewable. It is part of that carbohydrate economy that sustained us for thousands of years. It just cannot meet our current energy appetite.

Yet we have to ask whether we will one day move beyond combustion technology? Maybe we will do just the opposite and go back to a pure carbohydrate economy. Only time will tell . . .

In any case, we should get first things first. Home builders and remodelers should first question how they can take the money they would spend on a wood burning / natural gas / oil appliance and use it to improve the building envelope, eliminate the importance of said appliance. Then, if it is still needed, use the most efficient and most appropriate technology in their area.

Sounds like Passivhaus (or something very similar) to me!


13.
Mon, 06/07/2010 - 14:05

Very good post Daniel
by adkjac upstateny

Helpful? 1

Thank you


14.
Mon, 06/07/2010 - 22:24

I agree, Martin....
by Ed Welch

Helpful? 1

The only positive side to sight-unseen pollution from electricity generation or other sources may be that it keeps the peace in the neighborhood. When my neighbors crank the wood burning and the smoke drifts towards my house, I am not a happy camper!

Yes, Daniel, Passivhaus or something very similar seems to be the only answer. We need strong energy consumption benchmarks from organizations such as LEED and others....meet it or yank the certification! Passivhaus is the only green building program that demands ultra low energy consumption to get the certification.


15.
Tue, 06/08/2010 - 08:25

Drifting smoke...
by Ed Welch

Helpful? -1

I think you could make the case that consistently breathing PM from wood burning fires would be much worse for those individuals than the longer term ill effects of global warming, etc......just as it would be worse for individuals to be in the path of coal burning smoke as opposed to suffering the long term consequences.

Smoke drifts a long way, much further that just the neighbor's house. On a cold clear winter day, look down hill as the smoke hugs the earth. I've had urban air quality experts tell me that city folks are as impacted by the lingering PM from rural areas hundreds of miles away as those affected by ground level ozone being caught in the hills. I'm not sure if that guy was just getting defensive because I was pointing the finger at urban areas for generating ozone, but I do know PM travels a long way and lingers for a long time.

It would interesting to have an air quality expert comment on this post about how far PM can drift under certain conditions. They can usually be contacted at the various Air Resources Boards around the country.


16.
Tue, 06/08/2010 - 08:52

Clean burning technology
by Randy

Helpful? 0

EPA has developed a standard and a qualification for new technology wood boilers. They are called Hydronic Heaters in this program. The new Hydronic Heaters that qualify for the Phase 2 program are extremely low emissions. These units produce heat with less particulate emission per BTU than indoor certified wood stoves. The technology used in most of the Hydronic Heaters on the EPA list of Phase 2 qualified units creates an extremely high temperature secondary burn that achieves efficiencies in the 80% and 90% range. The combustion efficiencies are even higher, 98% and 99% combustion efficiency. this means almost all the avialable carbon is consumed and turned into energy that can be transfered into usable heat for homes and other applications. This can be an important reducing fossil fuel usage and lowering the net carbon emissions. Many families can cut their carbon foot print by 25% to 50% by heating their home and domestic water using a new Phase 2 qualified Hydronic Heater and responsibly harvested wood fuel.
It is very important to use well seasoned wood for heating. Unseasoned wood contains about 50% water by weight. Seasoned wood contains 20% or less.


17.
Tue, 06/08/2010 - 09:43

RE: Drifting Smoke
by Daniel Ernst

Helpful? 0

Ed - I don't know if there is much difference between woodsmoke and other particulates in the atmosphere. What comes up must come down. It's just a question of when. Likely they stay up there longer than we expect.

Here are some articles that discuss Chinese coal power plants and their effect on the West Coast U.S. These sources state that coal power plant particulates cross the Pacific ocean in ~ one week:

http://www.huffingtonpost.com/huff-wires/20071104/coal-the-dark-side

http://www.nytimes.com/2006/06/11/business/worldbusiness/11chinacoal.htm...

And here is a California website that discusses some implications of wood smoke:

http://burningissues.org/car-www/index.html

"The principal activity of Burning Issues is the collection and dissemination of the latest science information regarding health effects, economic impacts, and individual actions to reduce and stop solid fuel combustion."

Oil and natural gas burn much more cleanly than coal and wood (orders of magnitude cleaner than solid fuels). This quality is countered by a host of other problems and unintended consequences. Do you think the people living in Gulf of Alaska or Gulf of Mexico are worried about wood smoke particulates, or the effects of oil drilling and distribution? What about the folks living near Gauley, WV?

http://www.americanrivers.org/our-work/protecting-rivers/endangered-rive...

I think Martin created a balanced perspective. In the end we all have to reduce our consumption and pick our poison.

Where do you live and what are your personal beliefs? Do you want point source pollution (power plants) OR non-point source pollution (woodburners)?

It reminds me of Gerry Spence (trial lawyer) writing about uranium mining. He struggled with the fact that his friends worked the mines that destroyed the prairies near Riverton, WY . . . and the idea that their work would be used to arm nuclear warheads. He asked an environmentalist friend her thoughts on the matter. She, too, struggled with an answer.

"People need jobs," she said. "We have to let them rape a little." (From Freedom to Slavery, 1993)


18.
Wed, 06/09/2010 - 14:16

Washington's criteria - stricter than EPA (list better too)
by Jeffrey Gephart

Helpful? 0

Where the EPA requires stoves with catalytic converters to emit less than 4.1 grams of particulate matter per hour and stoves without catalytic converters to emit no more than 7.5 grams per hour, Washington state sets their requirements for stoves with catalytic converters to emit less than 2.5 grams of particulate matter per hour and stoves without catalytic converters to emit no more than 4.5 grams per hour. Washington state also regulate factory-built fireplaces and masonry heaters (the EPA does not).
In addition, Washington state lists qualifying products in an easy to use spreadsheet where the EPA’s list of certified products is a giant PDF. To access the Washington state product list go to: www.ecy.wa.gov/programs/air/indoor_woodsmoke/wood_smoke_page.htm#Washing...
In my search for an advanced combustion fireplace insert last year I found the Washington state resources extremely helpful.


19.
Wed, 06/09/2010 - 14:57

All things must be considered.
by Sprite

Helpful? 0

When looking at the environmental impact of burning wood, one can not just look at the fuel itself. How much energy and pollution is used/created during the construction of the wood stove, the regular replacement of piping, the construction of the chainsaw, the truck to haul the wood, etc. Nothing is really as simple as we would sometimes like to make it.
Myself, I built a home 19 years ago (1800 ft2 with full basement that is conditioned) with tight construction and good insulation qualities. I use a geo-thermal heat pump. We use 3,000 kWh/year for heating and AC. I'm in southern Illinois, 4,700 heat degree days and 1,400+ cooling degree days. And, we don't open windows.
I know the power plant pollutes, there was pollution from the construction of the geo unit. But I think one needs to do a complete cradle-crave scenario before decisions on the best way to condition our homes are made. Rember, the least expensive and least polluting is another sweater and coat.


20.
Wed, 06/09/2010 - 16:08

Cleaner Burning Technology: Masonry Heaters & Green Fireplaces
by Aleeah Livengood

Helpful? 0

COMBUSTION and HEATING EFFICIENCY

The combustion efficiency of a heater measures its ability to burn a given fuel completely and without pollutants, thereby producing heat energy. When a piece of wood is burned, about 30% of the heat generated is supplied by the solids in the wood and 70% is contained in the gases released as the wood is heated. If the gases are not fully burned, they escape as wasted heat and smoke (air pollution) and often condense on a cold chimney as creosote, the fuel for chimney fires. Many of these gases do not burn until temperatures reach 1100 degrees.

Wood stoves and wood furnaces typically have relatively lower combustion efficiencies and relatively higher heat transfer efficiencies then masonry heaters. Metal transmits heat very well, in fact within minutes of the first fire being lit. Similarly, a wood stove heats the air instantly and immediately distributes this hot air into the home. However, this fast response comes with two critical drawbacks.

Firstly, it becomes very difficult to regulate the heat output so that it's comfortable. If the heat output is regulated by restricting the air supply the combustion efficiency drops causing a smoky fire, air pollution and creosote deposits. Secondly, combustion efficiencies are low because the heat is given off too quickly and the temperature of the fire is unable to build to the point of fully burning the gases. Most metal stoves and wood furnaces cannot be safely burned above 900 degrees because the metal becomes to hot. Not to mention they are not comfortable to be around when burned over 400 degrees.

Contrast this with masonry heaters, with thick masonry walls, which are slow to release their heat and therefore have moderate heat transfer efficiency. Moderate heat transfer allows the firebox to reach temperatures of 1500 degrees; totally burning the gases that create air pollution, increasing combustion efficiency, while the exterior is still only warm to the touch. Specifically, combustion efficiencies have been rated at 94.4% and heat transfer efficiency at 65.4%.

Environmental Issues
Incomplete combustion of wood creates biologically harmful particulate emissions or in simpler words smoke. The Environmental Protection Agency and individual states enforce stringent regulations on wood smoke emissions. In many states, wood stoves and fireplaces are being restricted and or completely banned due their poor combustion and excessive emissions.

Masonry heater’s use the latest burn technology which incorporates an over-fired combustion delivery and top down burning technique. The air comes through the door frame, feeding the fire from the above fuel load. This allows for complete combustion during the early stages of fire, as the wood gases burn above the fuel as soon as they are released. The top down burn assist this with the kindling placed on top of the main fuel load igniting quickly and promoting rapid gas combustion.

These innovations ensure that majority of environmentally harmful gases; compounds and tars are burned in the firebox, creating heat not pollution. Masonry heaters have been tested for emissions, demonstrating that they are the cleanest burning wood stoves in existence.

PM-10
Wood smoke PM10 contains creosote, soot, and ash. Most smoke particles average less than one micron (one millionth of a meter). Masonry heaters as a group have been shown in field testing to emit an average of 2.8 gm/kg of PM-10 emissions; compared with an average of 7.3 gm/kg for the best Phase II wood stoves.

Cost
A traditionally built masonry heater is admittedly more expensive because it truly is a work of art. However, there are precast options that are more cost effective that provide the same outcome as a traditionally built masonry heater.

Isokern GreenTech Fireplace
Earthcore Industries Unveiled the First EPA Approved Isokern GreenTech Catalytic Fireplace at the 2009 United Nations Global Climate Summit Conference. Earthcore’s GreenTech Standard Fireplaces are the first wood burning fireplace of its kind to meet and exceed U.S. EPA standards for fireplace emissions. The Isokern GreenTech fireplace is ready now to be specified and installed in homes and projects. The EPA Wood-Burning Fireplace Program Qualified system is a prefabricated, refractory modular fireplace designed for field assembly. The press release is found here: http://bit.ly/bOMoU9

Additional Links:

TreeHugger
http://www.treehugger.com/files/2005/09/mason_heaters.php

Cold Climate Housing Research Center
http://www.cchrc.org/docs/snapshots/snapshot07-08mh.pdf


21.
Wed, 06/09/2010 - 21:12

"Free" wood isn't really free
by Steve Schafer

Helpful? 1

The standing dead trees, fallen limbs, etc. in our forests aren't just firewood waiting to be harvested. They're also habitat for the many organisms that inhabit the forest. I have a standing dead aspen tree in my yard. Last year, a pair of Pileated Woodpeckers excavated a cavity in it, and raised two chicks. This year, a pair of Great Crested Flycatchers is reusing the same cavity for their own nest.

Likewise, thinning a forest is only beneficial if you look at it strictly from a timber production perspective. From a biodiversity perspective, it's much better to leave it alone.

I'm not at all against the use of wood as an energy source. But we do have to remember that there is no such thing as free energy. No matter where we get our energy from, someone is paying for it.


22.
Wed, 06/09/2010 - 23:55

Wood fuel and global warming:"black carbon" and VOCs
by SK

Helpful? -1

Nice, balanced article, Martin. One additional thing that should be mentioned is that even if wood fuels are harvested in a sustainable, carbon-neutral way, that doesn't mean wood is a climate-friendly fuel. The fine particulates you mention are being increasingly understood to be an important contributor to global warming through both atmospheric and albedo affects. On top of that there's the methane and the volatile organic compounds that are unavoidably released from relatively uncontrolled combustion of solid biomass fuels -- small quantities but high global warming indexes.

In most cases, the net global warming contribution is less than for the fossil fuel combustion, though still significant. But it all points to the validity of your final words... "improve your home's thermal envelope".


23.
Thu, 06/10/2010 - 03:05

Response to Jeffrey Gephart
by Martin Holladay, GBA Advisor

Helpful? 0

Jeffrey,
Thanks for the very useful link to the list of wood stoves that meet the state of Washington's strict particulate emissions limits. For readers who may have missed it, here's the link:
http://www.ecy.wa.gov/programs/air/indoor_woodsmoke/Woodstovelist_5-19-1...


24.
Thu, 06/10/2010 - 13:16

Green Homes do not Burn Wood
by John Brooks

Helpful? -1

People Burn Wood...
Most people do not live out in the boondocks.
Most People should not burn wood in their homes or in their neighbohoods.


25.
Thu, 06/10/2010 - 15:19

Response to Daniel
by Ed Welch

Helpful? 0

Sorry for the late response, Daniel, I was deeply engrossed in Passivhaus Consultant's Training Phase II for the last three days. And thanks for the informative links.

I live in the Sierra Nevada Foothills, about an 1 1/2 from Lake Tahoe....a very sweet, progressive community. And, according to the EPA, our county is the 12th worst Ozone polluted county in the nation. Summer heat, plus nitrous oxides (primarily from fuel combustion), plus VOCs (some naturally produced by trees and others from urban sources) produce Ozone which is held in our area by inversion layers. The primary source is the Greater Sacramento Area and the Bay Area. So I feel deeply affected by fuel combustion especially because I have small children....so we try our best to leave the area as much as possible during July and August.

And, like most forested rural areas, we also feel constantly threatened by the risk of fires during the dry season. So... people are encouraged to thin underbrush during the winter to reduce the fire risk. Understandably, (I guess??) they thin underbrush, rake leaves and burn like hell. People also use the abundant wood resources to heat their homes. I understand, but I still don't like it. PM is worse than Ozone. Burn the occasional campfire or utilize extremely efficient combustion devices as described above....beyond that, no thanks.

As I am sure most of us all agree, we need to reduce our dependency on almost all energy sources, through Passivhaus or other means. Reducing the risk of fire...geez....that is another animal all together.


26.
Thu, 06/10/2010 - 20:15

direct vent options for wood burning?
by xiphias

Helpful? 1

Interesting article and discussion. Long-time reader, first time poster with a question. We have spent the past decade ascending the energy-efficiency pyramid. Did solar DHW a couple years ago. Now ready to cover the rest of the roof with PV. We have a large chimney that shades some prime roof space for much of the year. (about 600W worth of space.....)

We live in a place where it is necessary to have an alternate heat source during prolonged winter outages, for which we currently use a catalytic wood stove (which has a Lyemance damper on top, that works great, BTW).

The chimney needs to have the upper 10 ft taken off to allow more productive PV. We want to keep burning wood as the alternate heat source, but need some kind of direct vent system.

What are the options? Would strongly prefer wood as opposed to pellets. We do the wood sustainably and the system works well.

Thanks.


27.
Sun, 06/13/2010 - 01:49

Gasification boilers
by John Klingel

Helpful? 0

Sorry if these were mentioned and I did not see them. Gasification boilers are not even in the same category as "wood stoves". Read about them at hearth.com if you'd like. They are the way to go, and they are not just "European". Fred Seton and others (Garn, I think, for one) are US inventions.


28.
Sun, 06/13/2010 - 03:15

Beware the Eco-Fundamentalists
by Riversong

Helpful? 2

"Passivhaus or something very similar seems to be the only answer."

When someone sees only one answer, you can be sure that he's wearing blinders and seeing the problem through much too narrow a perspective.

PassiveHaus takes our increasing isolation and alienation from Nature to it's logical (or illogical) extreme.

We need super-efficient homes because we have demanded so much of the earth's resources that we've nearly destroyed the ecosystem upon which we depend for our very lives.

We need super-efficient homes because we desire many times the indoor space that's really needed for essential shelter.

We need super-efficient homes with close to zero emissions because our exploitation of the earth's capital resources (ancient buried hydrocarbons) has allowed our population to grow to unsustainable levels (we are now consuming the equivalent of 1¼ earths and by 2050 it will be 2 earths).

We need super-efficient homes because we are no longer willing to live within the normal climatic changes of the seasons - we demand a uniform year-round indoor climate and insist on the "right" to live anywhere on earth.

We need super-efficient homes because we choose to live in smaller and smaller family units and "outsource" our children and our elders to institutions.

We need super-efficient homes, in other words, because we have created and choose to maintain a thoroughly dysfunctional civilization based on individual freedom and selfishness, which no amount of "greening" is going to make functional.


29.
Mon, 06/14/2010 - 05:48

Efficiency and Scale
by Robin

Helpful? -1

There are two things that seem to be overlooked in this discussion.

First, if we burned oil the way we burn wood, we’d all be dead. That’s because we’ve usually burned wood at efficiencies under 50%. It’s the equivalent of burning oil in a barrel. New woodstoves and gasification technology have increased combustion efficiency so my Tarm wood boiler is not your father’s wood furnace (nor is it the current state of the art that it was 5 years ago when I bought it!). Outdoor wood boilers were the wakeup call that even in a plethora of low grade wood, combustion efficiency is important.

Where I live in northern NY, people love these behemoths but it’s because they are finally able to get the same heat distribution with them that they did with their oil boilers but they don’t have the fuel bills. They cut their own wood and think it’s “free.” People think nothing of burning 50 face cord (over 12 full cord) of wood a heating season. My indoor wood boiler burns about 20 face cord…to heat two buildings. If wood becomes a serious commercial heating fuel, people will think twice more about efficiency since the price of the wood will move towards being on par with other heat sources.

The second thing is that it’s one thing for people living in the country or small villages to burn wood, the impact is small. But if wood becomes a serious fuel, the negligible impacts will become significant quickly. When we had 10,000 Model T Fords on the roads, they had a minimal impact on carbon emissions. Now that there are over 100 million vehicles on the road, the impact is staggering.

New York is drafting regulations on outdoor wood boilers. And they are running into opposition. One of the regulations that is drawing fire is the phasing out of conventional outdoor wood boilers (replacing them with low emission ones) in 10 years. People who bought these things expected to get more than 10 years out of them. How the state manages this issue will be a test of their ingenuity. Right now the impact of the emissions from wood boilers is primarily local—plumes of black smoke drifting onto neighbors’ property and into their homes. If the use of wood for heating increases several fold, the impacts will become regional and national.

My conclusion is that the wood as a heating fuel is appropriate in areas where it can be sustainably harvested and trucked no more than 10 to 50 miles. In any case, its use should be regulated for emissions AND efficiency. After all, a BTU of energy is a BTU of energy and each sustainable BTU has the potential to replace an unsustainable one.

Robin McClellan
Potsdam, NY


30.
Mon, 06/14/2010 - 13:01

Well stated
by Scott

Helpful? 0

It's nice to see a balanced view on wood-burning. Well-done!
A couple points I'd like to make as a suburban wood-burner. I get my wood from local tree services and neighbors who have trees fall on their lots. This wood other-wise goes to the landfill.
My EPA fireplace insert is designed to burn hot & clean using refractory brick & pre-heated air to ignite combustion gases in a 'secondary burn' chamber. I season my wood to below 20% moisture and burn hot fires with adequate air. The only time there is any visible smoke from my chimney is for about 15 minutes on start-up if the firebox is cold. My leaky old chimney is now air sealed, lined and insulated, and my fireplace is lined with reflective sheet-metal over rock-wool insulation. My natural-gas consumption was cut by about 70% year over year.
I certainly don't advocate urban/suburban wood-burning for all, but if you're willing to find a sustainable wood source, invest in the proper equipment, installation and education,it can be a safe, efficient and clean use for an otherwise wasted resource.
One the other hand:
Most homes in the U.S have a fireplace. It's one feature nearly always highlighted in real estate listings. The vast majority are notoriously inefficient (like -10 to 10% efficiency) and poorly designed. So people who light an occasional fire for ambiance get little to no net heat from the fire. They often operate the FP poorly and use wet wood that was sold to them as 'seasoned'. The result is an extended belch of black smoke up the chimney, back-drafting into the home of both smoke from the fire and of exhaust from other combustion appliances (due to depressurization of the house) and a thick crust of creosote building-up inside the chimney, threatening a chimney fire. When not in use the damper leaks conditioned air up the chimney and lets creosote fumes into the house, and the masonry creates a giant thermal bridge to the outside. The EPA exempts fireplaces from reg's proportedly because their purpose is not heating, but the real reason is obviously because it's simply politically taboo. So how do we expose the fabled fireplace as the Green-Demon that it is?
Now, about that firepit in the backyard....


31.
Wed, 06/16/2010 - 19:54

Is anyone here keeping up with Current Events?
by Frank Vigeant

Helpful? -2

First of all, getting local wood to burn, especially those who live in wooded areas is wonderful management for your local environment ie: Felled trees by age, animal or weather. The native indians always took their wood from felled trees, branches, or limbs that were causing tree growth problems such as branches cutting off another one. They felt it was their duty (and I believe it is) as caretakers of the earth to help maintain healthy forests and wilderness.

If you want to look closely enough, there isn't a damn thing left in life that doesn't have some kind of negative health or environmental effect. Everyone is talking electric cars, solar panels, wind energy, etc.

Where is the EXTREMELY corrosive battery acids & chemicals going when we have THOUSANDS OF TONS of car batteries lying in land fills that don't make it to the recycling center? What about the chemicals and plastics from the solar panels when the house gets ripped down or augmented and get thrown away that don't get recycled? What about all the waste and byproducts from recycling plants? How are we going to make all these HUGE windmills without smelting huge amounts of steel & metals? What about all the grease, wire, wire housing, paint, plastics that make these wind turbines run????

Most environmentalists out there (except the militant and extreme ones) are well intentioned people but they are single tier thinkers. They have not taken the time and/nor have the capacity to critically think about issues and see beyond the first emotional knee-jerk reaction to a "supposed" good idea such as "save the planet." They do not see how the first thing affects the second which affects the third, which affects the fourth, and so on and so on. Even if they can see beyond the first thing, they don't see how each further step branches out and affects 3 more peripheral things , and each of those affect three more things, etc, etc.

There is more and more evidence that is leaking out that "Global Warming" may perhaps be the biggest scam to be put on the human race in centuries. It's now been proven that the Ctr for Int'l Climate & Environmental Research have thrown away old temperature & environmental data and fabricated false numbers and readings to promote the idea of "Global Warming" or "Climate Change." They have official protocols on how to "deal" with those who question the validity of global warming with more fabricated stats & reports. Reports that the glaciers melting in the himalayas were false. It was s bold faced lie.

More and more reputable scientists are finally getting recognized and some have completely changed their previous stances admitting that they "went along" with the "global warming" theories in order to get funding, and they are saying that there is no global warming, and if there is, it's 1. so negligible that isn't having any deleterious effect on the planet, and 2. Mankind is not affecting it in any way. It is a planetary cycle, and throughout the billions of years, the planet has baked and frozen over and over and over again.

I'm all for alternative fuel sources. I'm all for releasing the chains that come with depending on foreign nations for our energy needs. I'm all for less pollution in our air, land, and water, but I am sick and tired of first tier thinkers and people who have taken this environmentalism on as religion (and let me tell you.. it HAS become a religion to many people), and those who aren't so much concerned about the environment as they are of realizing their ultimate political and economic agendas that have NOTHING to do with the environment, but rather destroy existing socio and economic policies and realities.

Let's all take a step back, do some critical research and ESPECIALLY some critical THINKING, before we continue with the "sky-is-falling-and-we-have-to-act-IMMEDIATELY-and-DRASTICALLY CHANGE-EVERYTHING-to-stop-global-warming" attitude which as it looks more and more, may not be happening at all. Otherwise, we are all going to look mighty foolish. More so than we already do.


32.
Sun, 06/20/2010 - 14:27

environmentalism as a religion
by Jeff W.

Helpful? 0

Amen to that Frank. The religion of environmentalism is arguably the fastest growing faith in our world today. There is no sanction of. it in the public arena. As a matter of fact it is there that it is most ardently preached. Do not bring religion into our public schools...unless it is the religion where we reverence the creation. I am all for being a good steward of all that we as humans have been blessed with. We should do our very best to intelligently and thoughtfully extract what we truly need from our surroundings. The whole "save the planet" phenomenon is nothing more than mankind proudly raising his status to that of ultimate savior. Let's keep studying all aspects of building and resource conservation and alternative fuels and good stewardship but let's get real when it comes to the need for us to save the earth. If it is indeed so fragile (see thepriviligedplanet.com) perhaps we should ask ourselves if there's not someone overseeing our best intentions


33.
Mon, 06/21/2010 - 14:10

My God needs to step forward and denounce religion!
by aj builder, Upstate NY Zone 6a

Helpful? -1

Concentrate folks... I think we all know that burning a tiny bit of wood in a small superinsulated passive solar home in a world with way less religious folks plopping out 20 offspring each so as to enhance the number of zealots that believe in god x... as opposed to god y... and... now I am really laughing... the thought of "critical thinking"... in the same paragraph as religion... this is too much for me!.... where was I? ... oh yaa... burning wood smartly... gasified tech is amazing... a home that may only need a chord of wood... yeah. and OK in many rural areas and not ok in many closed valleys like LA or Albuqurque. And no... the big smoldering stoves should be banned. Too bad if you bought one... it was a mistake... live and learn.

Jeff... what is this blessed blah blah?

Frank.... from Fox news Koolaid land... fair and balanced... I like a tiny bit of Fox reporting and a tiny bit of Maddow la la nutty talk... and (I like you)... think the free debate of all is the best thing since Roman democracy days... I am mostly like you in that pollution is the number one part of our democratic capitalistic country that needs to be gone after like a nutty green zealot goes after global warming. Lake Erie was a mess and is now doing much better... Why... because the federal government took action, past laws, started the EPA... made regulations with scientists aid(no blessed religious aid) ... and here we are with a much cleaner enviroment than 1970. For all the Palin's out there that want zip regulations... I suggest yaa all live at the end of a discharge pipe from one of your favorite industries.

But... Frank... My point to you is... I think people like you(and Palin) and I should just go with the flow as to climate change... Why? because Climate change advocates want what we want in round about terms... less pollution! Less reliance on imported energy! Though we are not on the same page to do with the climate... we both are hunting for the same benefits ultimately... yes? O course we are... And time will answer this climate change question real soon... 5 decades have past for me... quickly... the climate folks are predicting doom in years... we will be in those years very very soon. And hey.... if true... we all mobilized for WWll in four short years quick enough to make millions of aircraft, guns, boats, ammo to kill millions and millions of our beloved brethren... we sure can do it again... and again I bet.

http://warchronicle.com/numbers/WWII/deaths.htm
We were able to reduce CO2 output... by killing over 48 million users of the non stinking stuff.
Good job Grand dad... leaders... dictators... Popes... we the people (sheep).. way to go

so... yaa... i can't concentrate that's for sure...

me... be burning a chord rurally... in a climate that can handle one chord gasified. Deal with it or come yank it out of my house. Bring beer if you come... Sam Adam's Lager preferred.

My population point is... less is more... sustainable earth is about balancing the populations of living things (including humans) with what the enviroment can support. Populations collapse when the balance is surpassed. Basic stuff here... no real need for a doctorate. Yes.. tech is easing the burden and allowing ever expanding human population numbers for now... but really... here's my main point. Selfish religious or personal choice to have baseball team numbers of offspring... wouldn't work if every single one of us did so! So if we can't all do it... none of us should. Equality is number one with me. Freedom is next and after number one.

Go tech... and go birth control! Best by far answer to our future and best way to go green.

IMHO........................

Oh... and two big booh yaas for the internet and discussion boards!


34.
Tue, 06/22/2010 - 16:23

And there it is
by Frank Vigeant

Helpful? 1

Adkjac, although I enjoyed your barely cohesive post and I too am a fan of free debate.

"So if we all can't do it... none of us should." What a revealing philosophy. Straight from a childish mind ala, "Whaaaa, he's got a bigger piece of cake than I do... that's no Fair!!!! Whaaaa" Grow up.

When you put equality before freedom you will quickly find that there is no freedom. History proves this again and again. And when you finally reach your holy grail of "equality" you'll find that everyone is EQUALLY living in squalor, equally without freedom, equally without liberty (btw, My two favorites - freedom & liberty - , for without those you can have NOTHING), equally without any quality of life, and equally without any equality. Wow, what a great world that would be.

Equality of OPPORTUNITY is an INCREDIBLY important issue and should be pursued rigorously in society. After all, it's one of the basic tenants of our nation. Unfortunately, too many people have confused "Equality" to mean "Equal OUTCOME." And that is not only an impossible goal, but a foolish one at that.

We are not born equal. Some are born with more intelligence, more artistic talent, more physical talent, more athletic talent, more mental and/or physical strength, some have natural acumen in writing, some in mathematics, some in sciences, etc, etc, etc. Therefore, equal OUTCOME can never be achieved. And fortune and history has never been kind to those who have tried to force it. History has taught us this over and over again. A shame that the only thing we've ever learned from history is that... we've never learned from history.

And to say that "pollution" is the number one part of our democratic and capitalistic country is absurd. As I said above, we certainly could have done better and still can on the pollution front, but I'll take our environmental record in a second before the likes of the Soviet Union, China, North Korea, Cuba, Vietnam, Cambodia, etc (Btw, all the countries that ALSO put "equality" before freedom).

So sorry my friend, I can not and will not go with the flow of Climate change. Intelligence and integrity prohibits me from abiding idiotic fallacies.

Your facts are lacking, but what you completely are void of is wisdom. A shame that 50 years hasn't given you any of that.

Oh, and I second the enthusiasm for the internet & discussion boards!


35.
Tue, 06/22/2010 - 21:33

Frank... i agree with most of your thoughts
by aj builder, Upstate NY Zone 6a

Helpful? 1

Frank... reread my post. I am not a raving climate change guy. I never said the USA is polluted like the worst of nations. No. But the world is one community now. Pollution should be a priority not gobbling fossil fuels. Don't you agree? And as to climate change... use it in our favor to get the ball rolling away from nonrenewables. You do agree they will not last for millions of years don't you? The world is growing in E use and population. Something got to adjust and the earlier the better don't you agree?

And I never said people are the same. That is not what I mean when I say equality is important. I am like you exactly as you state,

"Equality of OPPORTUNITY is an INCREDIBLY important issue and should be pursued rigorously in society. After all, it's one of the basic tenants of our nation. Unfortunately, too many people have confused "Equality" to mean "Equal OUTCOME." And that is not only an impossible goal, but a foolish one at that."

Most all of your post could be mine... with one exception. I have no need to form an opinion as to whether climate change is happening via man's last century or two on the planet. I don't care at all.

Pollution is and always will be a problem for all creatures.

Equality is always going to be a problem as all creatures are pretty selfish. Most have to work at it to be less than selfish. Me included.

Equality... yes... you may write better than I... and yes... we both get to equally post here. Boo yaaa!


36.
Wed, 06/23/2010 - 10:31

Can't argue at all with your clarification
by Frank Vigeant

Helpful? 1

Can't really disagree with anything in your last post my friend.

I absolutely agree that pollution of all types should be minimized if not eliminated. So long as we don't ruin everything else while doing so. Unfortunately, the "Green" nazis can't see the forest through the trees, and as far as they're concerned, it should ALL be done immediately, to hell with the consequences (even though they have no idea of the consequences of their actions, and if they do, they don't care).

So I guess in the end, we can agree to agree. Nice dialogue.


37.
Sun, 09/19/2010 - 14:38

Biomass a Burning issue
by Mark Siddall

Helpful? -1

Another paper from the other side of the pond that may be of interest:
http://www.aecb.net/PDFs/Biomass%20-%20A%20Burning%20Issue%20-%20AECB%20...


38.
Tue, 09/13/2011 - 13:17

some issues missing in this article
by Lyle Axelarris

Helpful? 0

A few important considerations seem to be missing from this article.
1. "the woods are full of unharvested fuel, including standing dead wood, fallen limbs, trees knocked down by ice storms, and stands of dense forest that would benefit from thinning." - We should be very careful using this logic. Without further discussion of the forest ecology, this statement alone demonstrates an ignorance of the essential habitat and nutrient cycle contributions that trees make after they are dead. This line of thought has been used diabolically by the timber industry to justify "salvage logging" all across the West. On a small scale, it can be sustainable, but let's not spread the myth that dead trees are just "unharvested fuel", because they can be prime nesting and perching resources for countless species (and food for the vital decay organisms which ultimately feed the entire forest).
2. PM10 is discussed, but much more insidious is PM2.5, which is responsible for up to 60,000 deaths each year. I live near Fairbanks, Alaska, which is not a typical 'urbanites romaticizing about nature' locale. Our extreme temperature inversion in winter and the local topography (valley/bowl) traps woodsmoke, accumulating to extremely unhealthy levels. If everyone had an EPA-certified woodstove it wouldn't be a problem, but many homes have converted to outdoor wood boilers (which, ironically enough, are the subject of ads on this document as it is published (attached) on the LBC website), which are grossly inefficient and notorious polluters. Some schools in Fairbanks have PM2.5 levels over 10X the EPA limit on school grounds. Recess gets cancelled on bad days, and 4 children suffered asthma attacks on the same day in one school!!

Any discussion of forest product use is woefully inadequate if only carbon footprint is considered. Our forests are SOOOO much more than carbon sinks, let's not ignore habitat, water purification, slope stabilization, thermal regulation and the multitudes of other biological, chemical and psychological benefits of the forests (and yes, I am talking about on the local level). And if we are going to burn wood (such as I do, with a pellet stove), we need to make sure it is as efficient as possible. Outdoor wood boilers are monstrosities that should be illegal; efficient wood stoves can be great is used responsibly; pellet stoves are an excellent use of "waste" material that provide the best thermal efficiency of almost any type of heating device.


39.
Mon, 10/29/2012 - 06:06

adding fuel to the fire...
by David Gregory

Helpful? 0

...and burning down the house to stay warm? ;)

...sorry, couldn't resist...

Some thoughts on things that seem missing / under-emphasized / mis-represented in the article and/or discussions so far, and some brainstorming:

1. Plants sequester carbon underground in the form of roots, and on the ground in the form of leaves and other detritus, so annual 'growth' is not equal to its above-ground woody biomass. [Trees store somewhat more above ground; grasslands store most underground.]
2. Relatedly, biomass left to rot does not release an equal amount of carbon into the air as if it were burned; and certainly not at the same rate: rotting slowly over time, a fair bit of carbon (couldn't say how much, sorry) becomes a part of the humus on the forest floor, and works its way down into the soil through various pathways. Appreciate the comments regarding the value for other species of 'wasting' burnable wood.
3. Food for thought: How much extra insulation would 20 face-cord of wood add to a house if applied as another layer in the most efficient way possible, and how much wood burning savings/year? Same 'net present value' issue for petroleum-based foams...(but we'd need to pick a discount rate that works for nature...)
4. Lunatic fringe: co-axial (condensing) direct venting? might condense out tars/creosote, though; and the cooler the smoke, the less it dissipates...scrubbers like coal plant smokestacks (with heat recovery)? At the cost of acidic holding ponds...and only useful where soils are too alkaline, which is usually where water (and biomass) is scarce.

no easy answers...but makes me want to dig into anaerobic digestion more...produce your own 'natural' gas, no fracking necessary...


40.
Mon, 10/29/2012 - 08:23

Response to David Gregory
by Martin Holladay, GBA Advisor

Helpful? 1

David,
Your idea of using wood as a type of insulation is not new, of course. Wood has been used that way for hundreds of years -- for example, when logs are used to build the walls of log homes, when hippies build so-called "cordwood homes," when sawdust is used to insulate double-wall homes (a common way to build ice houses in New England 150 years ago), or, these days, in the form of cellulose.

I think that anyone who wants to use wood for insulation should use it in the form of cellulose. That way you don't have to cut down any trees -- just take some paper pulp from the recycling stream.


41.
Thu, 09/19/2013 - 11:32

Energy efficiency first
by Ed Dunn

Helpful? 0

As always, if one starts with building a tight, well insulated envelope, and, if possible, use the sun, then there will be a significant less need for any type of auxiliary heating. Here in Flagstaff, on the high plateau at 7000', we heat only 5 months a year while conventional homes are heating 6 to 7 months. Our heating bill is 20 percent of what the average is. The bonus is we have a very comfortable house!

When we go on trips in January, I turn the heater off. Lowest temps recorded inside have been 54 over three days with outside temps down to zero.
Some large urban areas, such as Phoenix, to the south of us, should not ever even need to turn the heat on, much less burn wood. Los Angeles, NYC, and other large metro areas could cut heating needs by tending to the envelope.


42.
Thu, 09/19/2013 - 14:31

Response to Ed Dunn
by Martin Holladay, GBA Advisor

Helpful? 0

Ed,
I agree. Your point is the same one I made in the last three sentences of my article: "No matter what kind of fuel you burn, strive to improve your home’s thermal envelope. Plugging your home’s air leaks, improving your home’s insulation, and adding storm windows will save you money and reduce the amount of wood you need to burn. That’s good for your pocketbook and good for the planet."


43.
Mon, 03/24/2014 - 15:15

How much wood smoke reenters buildings?
by Jonathan Beers

Helpful? 0

Is there field research to back up this statement from an EPA publication? Thanks for any help

"In addition to the smoke that can be released inside the home, studies show that an estimated 70 percent of smoke from chimneys can actually reenter the home and neighborhood dwellings"

http://www.epa.gov/burnwise/pdfs/woodsmoke_health_effects_jan07.pdf


44.
Mon, 03/24/2014 - 15:28

Response to Jonathan Beers
by Martin Holladay, GBA Advisor

Helpful? 0

Jonathan,
I don't have any independent data on this question. I think that the operative word in the quoted sentence is "can." In other words, it can re-enter -- a different statement from "it re-enters."


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