Is burning wood really carbon neutral?
This fundamental question keeps coming back to me, and I have proposed it previous posts. But before hitting your “flame this toothless tree-hugging moron” button (again), realize this question is not as simple as it appears.There are numerous sites incorrectly making the unqualified statement that burning wood is carbon neutral. See for example, this statement The Boston Globe recently published on its website, in an article about Bennington (VT) College’s plans to heat with wood:
Supporters of wood chip heating say it is “carbon-neutral,” in that carbon released when trees are burned is absorbed when new trees are planted or seed naturally to replace them. The DPS Web site says most wood chips in Vermont come from mill waste or from culling low-grade trees from the state’s forests.
Or this, from the Natural Resources Council of Canada:
Wood is a renewable energy resource. And because trees recycle carbon dioxide, wood burning doesn’t contribute to the problem of climate change. As well, advanced combustion technologies mean more heat and less smoke from the wood you burn.
Or this, from the UK’s The Guardian newspaper, which makes is sound irresponsible to not burn wood:
Initially the power station will burn forest residue - sawdust, branches and offcuts from a local sawmill. “If this residue wasn’t burnt then it would just rot down and produce carbon dioxide anyway. We can speed this process up by burning it and producing heat and power at the same time,” says Reay. The power station not only reduces reliance on fossil fuels, it will harness energy from something that would otherwise be left lying around.
Without further digging into the details (only one of the above articles makes any qualification, and only in its very last paragraph), one could read the above statements, coming from quite reputable sources, and conclude that firing up the woodstove is a positive step toward mitigating global warming.
So, right or wrong: is burning wood, or any other renewable material, really carbon neutral?
Answer: generally, no. But sometimes, yes. And here’s why.
The usual argument for wood being a carbon neutral fuel goes something like this: as a tree grows, it sequesters carbon in the form of its wood structure, through its exchange of carbon dioxide for oxygen with the atmosphere. When the tree dies and rots, the carbon is relased to the atmosphere and soil through decomposition. Similarly, in burning the tree’s wood, the carbon is returned to the atmosphere, largely through carbon dioxide and other gases, where it can then be re-absorbed by other trees.
Let’s assume for sake of argument that the amount of the tree’s carbon that returns to the soil during decomposition is negligible. That is, let’s assume that if a live tree contains 100 pounds of carbon, those same 100 pounds are released to the atmosphere as carbon dioxide, whether the tree simply rots, or is cut and burned. Thus, the argument goes, the carbon is merely looping in a cycle between the atmosphere and temporary sequestration in wood, with a cycle time of perhaps 50 to 100 years. Over the lifetime of the cycle, no net transfer of carbon to the air results in the process being carbon neutral–or so it seems.
But what happens when trees are cut and burned faster than they are replenished? If a forest is being harvested for fuel at a rate of 1000 trees (or cords, or tons, or acres, pick your unit) per year, but less than 1000 units per year are regnerated via regrowth, then carbon is being dumped into the atmosphere faster (by burning) than is being removed (by tree growth).
Hence the real issue is to not simply be carbon neutral, but rather carbon rate neutral. If we take as a bare minimum definition that to harvest wood “sustainably” we must at least meet the condition that we are not harvesting faster than we are regrowing, then we can say that burning wood is carbon neutral provided the forest resources are being managed and harvested in a sustainable practice.
More simply stated, if not harvested sustainably, then no: burning wood is not carbon neutral. Some resources on the web make that critical qualification; others do not, or consider it to be a detail that can be buried in the last paragraphs.
An interesting sidebar to this question is that the cycle time plays a key role in the analysis. If the fuel to be harvested matures quickly (hay or bamboo are good examples), then the cycle time can be measured in a few months or a couple of years, rather than in decades. The fuel can be harvested and burned faster, but the fuel’s energy density, in terms of BTUs per acre of harvest, is much lower. It seems likely that there is some optimal combination of energy density, carbon density and cycle time among the available renewable fuels. I’ll explore that more in later posts.
Lastly, in terms of cycle time, we can also look at the other extreme. Consider an example where carbon is released into the atmosphere; is absorbed into plants in exchange for oxygen; is consumed by animals as food, then dropped as fecal matter and decaying carcasses; becomes buried by successive layers of sedimetation and glacial deposition processes; gets geothermally cooked; then is extracted as crude oil and burned.
Approximate cycle time for the above? Very difficult to say, but as a rough guess, perhaps anywhere from 1 million to 100 million years to go from carbon to a recoverable field of crude. A back-of-the-envelope estimate at the sustainable “harvest” rate of crude oil would be the total volume of crude that existed at the start of the oil age (roughly 2-3 trillion barrels) divided by the cycle time. This calculation yields a sustainable harvest rate somewhere in the range of 20 thousand barrels to 3 million barrels per year. The current worldwide oil consumption rate is roughly 30 billion barrels per year. Not carbon neutral.
For further reading, some follow-on posts:
- But why wouldn’t wood be good? (part one); and
- But why woudn’t wood be good? (part two).
Posted: Tuesday, Jan 30, 2007 8:56 pm by adam
File as: Climate Impact; Energy
Comments
Comment from Dave Brooks
Time: Monday, Feb 5, 2007, 12:05 pm
Exactly: Time scale is the key. Burning wood is not carbon neutral this week because it puts more carbon in the atmosphere. It is roughly carbon neutral over decades or a century or two, because the tree would have died and released the carbon anyway, and because a forest regrows, slowly removing carbon that the burnt trees produced.
But even if it were possible to switch every oil/coal power plant in the world to wood tomorrow, we’d still be increasing greenhouse gases at a huge rate - so in that sense, it’s not carbon-neutral. Not like wind power or tidal power or solar power - or the best alternative: conservation.
Comment from adam
Time: Monday, Feb 5, 2007, 6:49 pm
Dave, well said. Another point is that if the forest doesn’t ever regrow, perhaps because the land has been developed, then the carbon balance is even further biased toward increasing atmospheric CO2.
And I wholeheartedly agree about conservation, the least expensive of any energy source.
Pingback from GraniteGeek
Time: Friday, Feb 9, 2007, 8:52 pm
Is burning wood really carbon-neutral? DavidBrooks | 05 February, 2007 11:25 At the risk of blog-rolling, check out a good discussion on SeacoastNRG (”Seacoast energy”) about whether burning wood for power is really carbon-neutral. Answer: Yes and no, depending on time scale. This is of interest to us because PSNH recently converted
Comment from Josh
Time: Tuesday, Feb 27, 2007, 6:03 pm
But … when wood is burned the btu output is from the oxydixation of carbon and hydrogen and some alcohols. Depending on what fosil fuel is being burnt the co2 to btu ratio is different. When burning wood the products of combustion are co2 and water idealy.Also as a wood lot is managed properly the dying and mature trees are harvested in effect allowing faster growing undergrowth to absorbe the co2 created from the rapid oxydation of wood. In stark contrast any decent coal is in the 90%+ range of carbon content. When burned the ratio of co2 to btu is much higher than when wood is burned. The time consideration of these two fuels can’t even be compared. My hat though is tipped to the idea of conservation.
Comment from adam
Time: Thursday, Mar 1, 2007, 8:12 pm
Josh, thanks for your comment. I think we are saying much the same thing. If the woodlot is managed well, then burning the harvested wood can be carbon neutral. I’m certainly not advocating that coal is a better fuel. But I argue with the belief that burning wood or other biomass fuels, without proper management, is carbon neutral.
Comment from Haraldur
Time: Saturday, Apr 21, 2007, 6:17 pm
Why does everyone forget the oil used to be plants? would that not in the long run say that burning oil is co2 neutral too 
has anyone ever calculated how much co2 is emitted by forrest fires? or volcanos? volcano can drop the average world temp by as much as 9 degrees celsius over one year,
its short term shure but if one volcano can do that in the course of an eruption lasting few weeks, how can the emmissions from our futile workings that scientists say is a mere fraction af a degree matter? dont get me wrong im all for treating the evironment with respect and care but for the right reasons, and with all the facts included.
there has been global warmings before in earths history without “help” from man so how is it different this time?
Dont tell me this time its the cars and factories and so on without stating facts about the natures own emissions too.
We should fight globalition and the big multi national companies that think first and foremost about profit regardless to how they treat the environment in the process co2 os not the biggest enemy what about toxic waste?
im starte to ramble so i stop here
Haraldur
Comment from adam
Time: Sunday, Apr 22, 2007, 10:59 am
Haraldur, thanks for your comment. I have to disagree with some of your points, though.
I did some quick research that suggests “natural” sources of CO2, such as forest fires and volcanoes, amount to perhaps a few hundred million tons of CO2 emissions per year, where as human activities generate over 10 billion tons per year. In other words, fires and volcanoes amount to just a few percent (likely less than 5%), of the anthropogenic CO2 emissions.
Some of the largest eruptions on record did produce global cooling, although I could find no evidence of the magnitude you suggest. Five deg C seems to be the largest level of cooling I could find, and the cooling seems to be due to sufuric gases and particulate matter that reflects solar energy back to space before it hits the lower atmosphere. These cooling events are relatively short-lived, perhaps a couple of years.
I still remain convinced that the scientific community is right in asserting that anthropogenic emissions, largely CO2 and methane, are responsible for the warming and climate changes are are observing now. Though the temperature changes are just on the order of a few degrees, the changes appear to be part of a long-term trend, and not just a spurious natural event that will damp out in a few years.
Pingback from UrbanWorkbench | Sustainable Engineering Designs for Life
Time: Wednesday, Jul 4, 2007, 9:34 pm
Comment from Cate
Time: Thursday, Jul 5, 2007, 8:20 pm
Shouldn’t we also consider the source of the wood being burned?
I am considering switching my home heating system to wood burning and am concerned with this issue. I live on the east coast in an area that is rapidly developing. Naturally, the land around here is eastern boreal forest. Developers routinely clearcut large swathes of land, burning the cleared wood on site or hauling it to landfills, usually the former. If the source of my wood were to be this or another source of cleared timber, wouldn’t I actually be lowering the CO2 emissions by burning the wood in my stove and using the generated heat to warm my home rather than allowing it to be wasted in the atmosphere. This way, I’d also have stopped buring the natural gas I currently use to heat my home with the net result being a lowering in CO2 emissions, correct?
Pingback from that GREEN blog » Blog Archive » Is burning wood really carbon-neutral?
Time: Sunday, Jul 8, 2007, 11:21 pm
[…] an almost six month old (but highly relevant question) from SeacoastNRG, I have to comment on what Adam said. (You really should READ what Adam said first) His logic is […]
Comment from adam
Time: Tuesday, Jul 10, 2007, 7:02 pm
Cate, thanks for your very thoughtful comment and questions.
I think you are trying to address two issues at once. I’ll try to answer each one in turn. I’ll use the word “tree” here to generically describe trees, brush, vegetation and other plant matter that might be cleared and used as a fuel.
1. As you describe it, that practice would not be carbon neutral. The defining factor for me is how you described the harvesting of these trees: the land is being clear cut for development, and no counteracting measure for sustainable forest management is in place. That is, the developer is simply clearing (say) 10 acres of woodland for development, and is not taking 10 acres of developed land in some other place and planting it with trees. In terms of balancing woodland or forest, those 10 acres are now gone, and there is now a deficit of 10 acres for future absorbtion of CO2. If the harvested wood is then burned, the CO2 is spent to the atmosphere, and there is no 10 acres of new woodland to compensate.
And unfortunately, the compensating measure you describe, switching from natural gas to wood for home heating, wouldn’t be sufficient. In terms of a carbon-bearing fuel, it doesn’t get much cleaner than natural gas, which is mostly methane. Methane produces less CO2 per unit of energy than almost any other fuel. Wood is, unfortunately, more like coal in the amount of CO2 emitted per unit of energy. So in switching from natural gas to wood, it’s true that you’d stop emitting the CO2 associated with buring methane, but you’d more than make up for it by burning the wood. If you were switching from coal to wood, I’d say that was a good idea, as you’d be nearly eliminating all the other poisions (such as sulfur and mercury) that are emitted when coal is burned. But even then, I don’t think you could argue that your practice was carbon neutral without assuring that your wood supply is harvested in a sustainable practice.
2. I think the idea that you have latched onto is to somehow make better use of the wood that you’ve seen being clear cut for development. I’m actually quite surprised to hear of the practice that you describe. My observations in this area are that when land is cleared, the plants and trees are usually harvested for lumber and/or chipped up for fuel or mulch. I definitely agree with you: it’s a shame to have good trees or other biomass simply wasted in an open-air burn pile, or buried. So from this standpoint, if that wood is going to be burned, would I rather that you heat your home with it, or have it chipped and burned to generate electicity, instead of simply wasting the heat to the atmosphere? Yes, I would, and I could probably justify the practice on that basis. But I wouldn’t claim it to be carbon neutral. And I’d also ask myself the question, what if everyone were to follow that same practice? That is, what if everyone switch to wood as a fuel, on the justification that it’s only going to be burned or rot anyway? What would the net loss of woodland acreage be then?
Comment from Ben
Time: Friday, Jul 27, 2007, 9:59 am
What an excellent discussion. As a consulting forester and biomass advocate, its nice to come across an intelligent conversation on carbon and wood energy. The opinions above makes sense to me, yet I have often wished that there were some intermediate term like carbon neutral to describe fuel derived from non sustainable land management practices. Eventhough land clearing chips may not be regrown on the same acre of land, they are locally-produced renewable fuel that is environmentally, economically, and socially better than coal and oil. Maybe “carbon improved” would work?
Comment from Adam
Time: Sunday, Jul 29, 2007, 10:24 am
Ben, thanks for your contribution to this discussion. Personally, I have difficulty with the current trend of trying to encapsulate the entire problem in simple terms, such as via the use of the word carbon. I’m not convinced that trying to be carbon neutral, or the buying of carbon offsets, are really all that effective, other than in trying to make us feel better about our consumption habits.
With regard to new terminology for biomass use, I think you’ve already described the best one: renewable. Of all the carbon-based fuels we have, only biomass is renewable in the scale of a human lifetime. And of course, biomass also has the added virtue of being (potentially) carbon neutral.
Thanks again for your comment. Let’s keep the conversation going.
Pingback from Carnival of Green Living #01!
Time: Wednesday, Aug 8, 2007, 8:08 am
[…] from Seacoast NRG asks the question Is burning wood really carbon neutral? posted at Seacoast […]
Pingback from StumbleUpon » Your page is now on StumbleUpon!
Time: Wednesday, Aug 8, 2007, 9:48 pm
Comment from mike
Time: Thursday, Aug 23, 2007, 9:19 am
hey:– Gald to be part of your debate . I would be intrested to hear views the life cycle analysis of “sustainable” afforistation or biomass production. While biofuels and biomass are considered greenhouse gas neutral this only applies to the consumption phase – the emissions generated during the production phase are considerable. Would a well to wheel analysis will show subatantial contribution to GHG emissions reductions?
Comment from adam
Time: Sunday, Aug 26, 2007, 2:35 pm
Mike,
A good point to bring to the conversation. I’m not that familiar with the life cycle costs of fuels. But on another post, a reader (Ben) added a very good comment with links about that very topic. I suggest you try there.
Thanks for participating.
Pingback from [v5.0] Detroit Luv :: dear minus
Time: Tuesday, Sep 4, 2007, 2:45 pm
Comment from Stuart
Time: Saturday, Sep 22, 2007, 3:02 am
Excellent discussion but the SCOPE is wrong.
Personal CARBON NEUTRALITY by burning wood, bio fuels, etc is hogwash. Its worth doing but don’t for one moment think its going to make any difference.
The discussion SHOULD BE about the overall (global) balance of carbon emmissions to the atmosphere versus eco absorbtion of this carbon rather than is Wood or Bio fuel burning “Carbon Neutral”.
We need to get back to a balance, or better still a negative balance, of carbon emmissions to the atmosphere.
Wood emmissions are less damaging than coal/oil since the cycle of emmissions/absorption is so different but BOTH fuels emit carbon at a rate greater than the carbon is removed from the atmosphere.
Therefore the amount of CO2 in the atmosphere continues to increase as a consequence of population growth, emerging economies and the ever growing personal emmission of carbon much of which is hidden in the manufacturer of “consumer” goods and our general “throw away” lifestyle.
Ever thought about how much energy is used to produce lets say you “throw away” plastic milk bottle?
Therefore the only solution is that we have to reduce the amount of Carbon we emit TO ZERO, or possibly develop a way to absorb this CO2 (feasible but the scale/cost is mindboggling!) and lock it away underground.
Carbon offsetting, bio fuels, individual “carbon neutrality” will all have some extremely limited impact but IF WE FAIL TO GRASP THE NETTLE we will not stop an ongoing worsening global balance.
I burn wood rather than coal/oil BUT not to be “carbon neutral”. Its just the natural thing to do when you live in the country and live a little closer to nature….but I still run my car(s) and also heat the house with gas and watch the TV using electricity that inevitably comes from burning fossil fuel.
IF we continue using power at the rate our society necessitates (unlikely to be any change here except through more efficient use of what we use) then this power MUST come from sources other than carbon based fuels.
Hydro, wind, solar power is the “no brain” choice but the potential availability versus existing and future projected consumption is just unrealistic.
I’m afraid you just cannot escape NUCLEAR and HYDROGEN (vs carbon) based fuel, if we are to maintain our current lifestyle.
Mind you our politicians would loose out on a potential bonanze of revenue generating schemes!
Comment from MichaelS
Time: Tuesday, Oct 16, 2007, 6:46 am
I’d like to see this conversation continue. I keep hearing that wood burning is carbon neutral but as said in this thread that is only very general and applicable over a long time scale, even if the wood that is being burnt is collected from deadfalls and the woodlot is maintained. There is no way we can generate enough new growth per year to sequester the CO2 released in heating one home without huge amount of land being dedicated to a woodlot. This is not very practical for most of us. (Even if that wood were to rot naturally and release its CO2 component to the atmosphere, it is really slow, I have some firewood that has been sitting in my back yard for over ten years and while it is rotting a bit, is still pretty sound and holding onto its carbon).
I like the term carbon rate neutral. This is an important concept for people to understand. Another concept to consider is dynamic equilibrium. The earth is in a state of dynamic equilibrium (a geomorphology term at least as I originally learned it). The process of constantly trying to maintain this equilibrium is a large driver of our weather systems (i.e.: hot air at the equator trying to equilibrate with cold air at the poles causing air movement and temperature mixing etc.). In a natural state, the amount of carbon released equates to the amount of carbon sequestered over time. Once we much about with the earth’s ability to keep things in equilibrium, we see changes from what we are used to as the earth moves into a new dynamic equilibrium, i.e. rising temps due to immediate increases in CO2. I don’t think burning wood is an answer to our problems or even a way to slow it down considering that we can not sequester enough carbon from burning wood to make it neutral in the short term which will cause an increase in CO2, i.e. not carbon neutral.
Don’t forget the environmental devastation caused by burning too much wood in overpopulated areas of the world and the various other constituents released from a wood stove even with a catalytic converter (dioxin, polycyclic aromatic hydrocarbons, etc).
Sorry to be a naysayer, but this is an important topic
Pingback from LIME Daily Video Podcast - LIME
Time: Wednesday, Oct 17, 2007, 4:10 am
out Western Disposal, the local trash company, accepts shingles as clean wood waste – along with other construction waste like 2×4s and plywood – that they grind up for mulch and compost. A much better option than burning, especially if you askthis guy. [IMG]
Pingback from www.sloughobserver.co.uk :: View topic - Slough Village Idiot
Time: Monday, Oct 22, 2007, 4:44 am
Comment from Hans Goksøyr
Time: Friday, Nov 2, 2007, 12:03 pm
In Norway:Fir tree logged at 100 yrs, life span 200 yrs,(max600) decomp takes over 100 years after death. I.e effekt of reduced decomp noticed after 150 yrs! Forest growth 3% p.a. Wood:0,4kgCO2/kWh, oil/gas:0,2 kgCO2/kWh. Conclusion:Forest should be conserved, energy demands met by H/C. Government policy subcedice woodburning in beliefe in carbon neutrality.
Pingback from U.S. Renewable Energy: More Burned Timber Than Wind and Solar - Beyond the Barrel (usnews.com)
Time: Thursday, Nov 8, 2007, 2:15 pm
Pingback from www.minnescraper.com :: View topic - Midtown Eco Energy/District Energy
Time: Monday, Dec 17, 2007, 11:59 am
Pingback from Yukon River, cloudy day in January on Flickr - Photo Sharing!
Time: Saturday, Jan 12, 2008, 4:31 am
Comment from stephen
Time: Friday, Jan 18, 2008, 4:41 pm
I’d agree with the original comments for sure and do like the term Cabon Rate Neutral…….the planet is in crisis we need Zero co2……in the short term natural gas and propane give off between 30 and 45 % less co2…to include the manufacturing of each (cutting wood trucking wood drilling and processing gas and propane) here in Vermont they have gone to state supported wood fire school heating plants under the guise of renewable biomass..some even have 1/2 million dollar smokestacks with cyclone scrubbers and filters to try and remove the heavy metals and particulate matter….what we really need is zero carbon emmissions…great dialogue thanks
Pingback from It’s better than bad, it’s good! (Day 343)… « Green as a Thistle
Time: Thursday, Feb 28, 2008, 11:23 am
Comment from T
Time: Friday, Mar 7, 2008, 8:48 pm
I know that, especially in urban areas, the life cycle of buildings can be mere decades–but (and a bit off the topic) would increasing the use of wood (if sustainably harvested) be a way of sequestering carbon? It seems like steel, and to a lesser degree, concrete are very energy intensive in their production.
Comment from adam
Time: Saturday, Mar 8, 2008, 3:02 pm
T, thanks for your comment. I’ve actually given a lot of thought to the idea of sequestering carbon in the form of lumber harvesting. If harvested sustainably, then it would be a way of removing carbon from the atmosphere. It would be interesting to run the numbers to quantify the effect.
Unfortunately, the worldwide situation now is one of a rapid loss of net forestation, which is having the opposite effect.
Comment from Derek Parker
Time: Tuesday, Mar 18, 2008, 11:03 am
On the topic of wood burning and being carbon neutral, there are issues of scientific fact and then there is the human twist.
I am an economist, so I won’t intervene on the science of wood burning carbon neutrality or lack thereof. But I will say, as someone who has spent a cold winter warmed by a wood stove, that there are many practical reasons to think wood.
First of all, I’ve been burning trees that have been killed by spruce beetles. I’m would guess this changes the equation on rate of rot and CO^2 release.
Second, our family has adapted to shifts in temperature and I’m amazed that my 3 young kids don’t get chilled so easily. Our home temperature varies from 16 degrees Celcius to 26 degrees (60 to 79 degrees F) with no complaints. We just put on sweaters and hoodies.
On winter days when the temperature is around -40 or colder, I’ll get up and warm things up…sometime let the furnace run for 10 minutes to keep things in the basement from freezing. My wood stove will keep hot coals for around 8 hours, so I can usually start up a fire from the previous burn.
Another point–I have to work to get things ready for the woodstove, so I tend to conserve and think conservation, not just to be kinder to the environment, but to respond to my occasional laziness. (I buy 16 foot lengths for firewood and cut and chop to suit.)
Anyways, as is often the case with analysis, there are many difficult-to-consider factors that go into the mix of investigating how much less carbon one uses in various scenarios. I am combining this along with riding my bike to feel better about what I’m doing to the environment.
Oh, and I’ve spent about $2,000 less on my heating bills.
Derek
Comment from kevin swan
Time: Wednesday, Mar 19, 2008, 10:47 am
My family has been installing multi-fuel boilers for thirty years. When you are able to burn wood, your entire building will be heated; when the wood fire dies down, a back-up form of fuel will supply the heat: electricity, natural gas, propane, fuel oil. The best of these systems is “wood gasification” in which the wood smoke is also burned. This does two important things:
First it decreases the amount of smoke and particulate that is emitted. While the sight of wood smoke curling up out of the chimney is a soothing sight, limiting those emissions is critical.
Second, the amount of energy that is actually used, the fuel efficiency, is nearly 90%. With a standard wood-burning stove or boiler, typical efficiency is in the 40-50% range. Worst of all, though, is a standard fireplace. Wood burned in an open fireplace may actually use MORE fuel than the wood provides, as air heated by the home’s central heating source is often used as combustion air. I weep when I see stacks of firewood outside a home with a standard fireplace.
My father had the foresight to plant trees thirty years ago for fuel. As some have said, if you have a woodlot, you control the cost, quality and availability of your fuel source. Try that with your local utility company!
Comment from adam
Time: Wednesday, Mar 19, 2008, 7:39 pm
Derek and Kevin, thanks for your comments, and I applaud your efforts to use a renewable fuel. I myself don’t argue with the use of wood or wood products as a fuel. I would do so myself if I could (I live in an apartment).
My objections are targeted at the claim that any use of biomass as fuel is, by definition, carbon neutral.
Frankly, I’d like for us to all get away from the carbon-neutral campaign, which I liken to a simple means of alleviating guilt without causing real change.
Comment from DamionKutaeff
Time: Sunday, Mar 23, 2008, 3:16 am
Hello everybody, my name is Damion, and I’m glad to join your conmunity,
and wish to assit as far as possible.
Comment from Steve
Time: Wednesday, Apr 2, 2008, 3:16 pm
I am looking at a potential “green” project in San Diego, where urban wood waste is to be diverted from a landfill with methane capture and burned in a traditional rankine cycle power plant. From a carbon emissions standpoint, which is better.
Pingback from India Development Blog: Blantant Plagarism
Time: Wednesday, Apr 2, 2008, 3:18 pm
Comment from adam
Time: Wednesday, Apr 2, 2008, 6:56 pm
Steve, I don’t really feel qualified to say which of the two would be better.
But I will hazard a guess that since the wood is buried and the outgassing methane is captured, the carbon impact of burying the wood might be less, if only because most of the carbon assumedly stays in the ground.
In evaluating a project, I think there are many more things to consider in addition to the carbon impact.
Comment from Patsy
Time: Wednesday, Apr 2, 2008, 7:43 pm
Thanks for sharing all this information. To pick up on the conservation aspect, I have a few questions:
- For landowners, if you can devote 50% of your land to trees/wooded areas, is this enough to help balance/counteract that owner’s usage? What would be the minimum acreage needed to do this?
- For national & state lands, can we implement any legislation to prevent further forest harvesting without replacement, such as high power utility line clearings, private sale, etc.
- Can we increase taxes on second homes & imports/exports to encourage conservation of these costs, including the gas needed to fly food around the world? Doesn’t “transport” account for a notable percentage of gasoline used worldwide, because people are not fully supporting their local economies?
Maybe we should schedule power outages like the one experienced on the East Coast a few years ago to help people remember to conserve, where Mother Nature is not already doing it through tornadoes, flooding, fires, etc. I think this was just done in a few cities, but not everyone knew to participate. We need something tangible to do which everyone recognizes as helping, since not everyone can plant new trees by their home.
I would be interested in “diet guides” for conservation and sustainability requirements for my lifestyle - any good references?
Comment from Someone
Time: Friday, Apr 4, 2008, 10:54 pm
Hmmm, so let’s say you have a whole heap of wood and branches and crap you need to get rid of that have been brought down by a storm, would it be better to burn them or take them to the tip (considering that they would break down faster in a tip that in a natural environment anyway)?
Comment from McKay
Time: Saturday, Apr 5, 2008, 12:35 am
Through this discuss of carbon neutrality of wood & biomass consumption, a parallel question strikes me:
OK, so we’ll assume that if wood is harvested and replanted sustainably, then wood is carbon neutral.
But I wonder: does the effect of burning and production of soot and other particles have its own effect on global warming (or other local air pollution issues) apart from just the CO2? Does anyone here know about that?
Even in the best theoretical case, there may well be more than simply balancing CO2. If we all managed to find a way to use sustainable biomass and burned it, what would the non-CO2 emissions do? I understand soot, mostly referenced to coal plants, can have a powerful climate effect. Would not wood have some similar potential issues? What would be required to avoid that secondary problem?
Comment from adam
Time: Saturday, Apr 5, 2008, 10:02 am
These are all very good questions and comments, and thanks to all for your submittals. Perhaps I should simply try to get a discussion board launched on this topic.
With regard to other gases and soot released when wood is burned, there clearly is an environmental impact. Obviously, not all of the gases released are simple CO2. I have to assume that methane, CO and other poisons are also present. Some of these are also greenhouse gases. Soot, I think, is more of a ground-level problem, and is clearly a health issue.
I seem to remember that back in the first energy crisis (ca. mid-1970s), there was such an increase in wood burning in Vermont that local ordinances were passed to prohibit the burning of wood for heating. The issue was that local air quality was being adversely affected, largely by smoke and soot. Does anyone have any more information on this?
Clearly, furnace and boiler technologies have improved since that time. The comment by Kevin Swan above has some information on the technologies that can reduce emissions and soot.
With regard to whether it is “better” to burn wood or bury it, I again don’t think there is one simple answer. If the wood is being burned in an open-air pile (as is sometimes done with brush), that seems particularly wasteful and polluting to me, since the heat, energy and waste products and simply being spent into the atmosphere. In such a case, I would propose that it is more environmentally benign to compost the wood, or bury it.
If instead the wood is being burned to produce heat or electricity, that is an improvement over an open-air burn.
But again, these are all matters of degree. If you are using the wood as a fuel, what are you comparing to? Does your heat normally come from coal? Then I am more encouraged to burn wood. Can you burn your wood in a high-efficiency gasification boiler? Then I am even more encouraged. Or, does your heat normally come from a high-efficiency natural gas boiler? Then the answer is less clear to me, and requires further consideration.
In the end, I think it’s important to simply remember that wood, or other biomass fuels, have the potential to be indefinitely renewable, and have a small environmental impact, compared to fossil fuels. The key, as always, is to try to assess not only the immediate impact, but also the sustainability of your efforts.
Pingback from Cut the Carbon « The Blog for Mister Bjerke’s Computer Apps Classes
Time: Wednesday, Apr 9, 2008, 11:42 am
[…] So many fallacies in the debate over global warming are based on incomplete information, it is easy to make changes in your life that don’t really result in a positive change. […]
Pingback from Fun with the Environment: Earth Day Games » Everyone But You
Time: Tuesday, Apr 22, 2008, 1:25 pm
[…] tree hugger before adding to fire). Whether or not it is actually carbon neutral to burn wood (it really isn’t), isn’t important. You’ll be able to fend off most Environmental Crazies with this […]
Comment from charl
Time: Saturday, May 3, 2008, 12:24 pm
Hi, i would just like to find something out? I have heard talks about people suggesting burning of biomass of alien vegetation, and even using it for biofuels? I am not sure of such a large scale operation would really benifit the environment, do you perhaps know if any research has been done about this?
Comment from Haudy Kazemi
Time: Tuesday, May 13, 2008, 12:33 am
One aspect you didn’t address in whether burning wood is carbon (rate) neutral is carbon that is indirectly released. Examples are the gas/diesel burnt to power chainsaws, log splitters, and vehicles to move/transport the wood from where it grows to where it is burnt. If you account for this fuel, burning wood is no longer carbon neutral, even if you grow an equal amount of wood each year as you burn. The liquid fuel carbon emissions will throw things off balance. However, it can still be said that burning wood (even with some liquid fuel on the side) is nearer to neutral than burning only liquid fuels.
An alternative option, described in more detail by some members of the hearth.com forums, is to use solar thermal energy collectors (and in cold climates, esp. solar evacuated tube collectors) to cover the base or average load, a large, insulated, hot water tank, and use a wood gasification furnace/boiler to cover variable seasonal demands. This combination can be adapted to full home heating as well.
Comment from darren quinn
Time: Wednesday, May 21, 2008, 9:25 am
I wonder, because i use roadside wood in natural surroundings where regrowth is obvious in all forms of bush.
And use a slow combustion wood fire. Plus planting trees myself either from nursery or ones I grow myself and replant out in the woods,Am I at least part carbon neutral..?
The most efficient form of wood heating being slow combustion,; open fire places use approx 8 tonne of wood per year…whereas th slow combustion uses approx 1 tonne.And my electricity bill drops in winter too i notice…so…am I..?
Comment from adam
Time: Wednesday, May 21, 2008, 12:24 pm
Again, thanks to all for your interesting and thoughtful comments.
It’s difficult for me, as the owner of this blog–but by no means an expert–to say that any one practice is clearly better than another, except in obvious cases, such as when comparing coal vs. wood as a fuel, and when harvesting wood sustainably vs wastefully.
Haudy above raises an excellent point, in that although the use of biomass as a fuel can approach that ideal standard we think of as “carbon-neutral”, the lifecycle analysis of biomass fuels would likely still tip the scales in favor of being non-carbon-neutral, since the planting, nurturing, harvesting and processing of the biomass materials into fuel all likely require non-sustainable practices of using fossil fuels for transportation, milling, etc.
Similarly, as Darren points out above, biofuels can be burned in ways that are truly wasteful (open air burning), or in ways that are truly admirable (high-efficiency gasification systems). But again, a true lifecycle analysis would still suggest that our practices, as a whole, would make carbon-neutrality a near impossibility, albeit likely a far better practice than using fossil fuels directly.
In short, it becomes quite easy to reach the conclusion that true carbon-neutrality is nearly impossible, and that the situation as a whole is hopeless.
But my position, and I hope this is just as clear, is that we are far from being in a hopeless position. But neither should we hang our hats on the idea that carbon-neutrality, or near-carbon-neutrality, is some cure-all for our problems. I think the problems we face are much more complex that trying to find a bumper sticker solution of carbon-neutral, or in the wholesale purchase of offsets.
My wish, and this is the true purpose of my blog, is simply to get people (myself included) thinking: about our impact; about our consumption practices; about the importance of sound and science-based energy policies; and about the importance of decisions that we often make in a trivial and unthinking fashion. The fact that this post remains so popular indicates that many readers are in fact applying that type of critical thinking to their own practices.
I don’t have simple solutions to offer, and can’t be the arbiter of such nuanced differences in personal practices.
But do let’s continue the conversation, and we can all benefit.
Thanks,
Adam
Write a comment