June 02, 2005
I point this out not because I'm in favor of it, but because I think it's a trend worth watching: the Klamath Falls, OR newspaper, The Herald and News is reporting on a project to use biomass--namely, thinned trees--to generate electricity.
Here's what the article has to say about the greenhouse gas effects of the project:
A major wildfire would release large amounts of carbon into the atmosphere. But the controlled use of that same wood for lumber or electrical production would be positive in terms of "greenhouse gas" emissions. Future fires would not release the same amount of carbon dioxide, the wood that goes into building products stores carbon, and the biomass that goes into power production offsets the need to produce that energy from fossil fuels.
To be clear, I remain skeptical -- but since I don't really know anything about the specifics I'll keep my mouth shut, and let wiser or more informed people speak.
But over the long term -- and if future prices for natural gas are as high as they're expected to be (link goes to natural gas futures contract prices) -- I can't help but think that the pressure for this sort of project will intensify. And that seems to be a cause for concern. Deforestation rates over the past 30 years have been high enough just to deal with demand for timber and wood pulp; adding electricity to the mix is, well, troubling.
Posted by ClarkWD | Permalink
I'm glad somebody quotes biomass burning's contribution to climate change.
Here are your global numbers: http://www.grida.no/geo2000/english/0040.htm
We can do a better job managing forest growth and use. Here's a piece from one of the recognized authorities on the subject:
Posted by: John Anderson | Jun 2, 2005 11:32:39 AM
I tend to agree. If you build an infrastructure to use trees to produce electricity, that infrastructure will not sit idle.
The quote was kind of confusing to me - if you take culled wood and build a house with it, the carbon is safely interred and out of the atmosphere. But, if you burn it? The fact that you offset fossil fuel use doesn't mean you're not releasing carbon.
Posted by: Jon S. | Jun 2, 2005 11:37:29 AM
Granted, the newspaper account is a bit muddy. As with so much about forestry, the effects will depend a lot on the actual on-the-ground land management practices. So far as I can tell,
1. Burning a tree in a wildfire releases the same amount of carbon as burning it in a power plant. The greenhouse benefit results from the fact that fossil-fueled generation is almost always displaced as a result.
2. Over the long term, if the land is kept in forest cover, the potential exists for biomass-fired electricity to be carbon-neutral, since the next generation of trees will suck that carbon back out of the air.
3. In many parts of the American West (the land around Klamath Falls included), a century of fire supression has filled the forests with spindly, fire-prone trees - trees which would have been thinned out by periodic low-intensity ground fires under previous management regimes. Thinning those trees is probably beneficial for the forest and for species which depend on older forests with multi-layered canopies. In addition, to the extent that such thinning makes a catastrophic wildfire less likely, it has the potential to reduce CO2 emissions which would not displace fossil-fuel generation.
Posted by: Seth Zuckerman | Jun 2, 2005 1:11:13 PM
Judging from the story, proponents of the project believe that thinning can reduce the chances of a catastrophic fire that burns down the entire forest. In short - we can burn a little now, or burn a lot later.
I'm not saying that this is true -- it's just what the article says.
On lumber and sequestration -- the biggest CO2 problem from deforestation is that it releases carbon trapped in forest soils; plus there's leaves, bark, and wood that never makes its way into lumber (and often is burned). So you're right -- cutting trees for lumber does mean that some carbon is sequestered, at least in the short term. But generally a far larger amount of carbon is oxidized and released to the air in the process. The forest soils impacts are probably less severe for thinning than for outright clearcutting.
(Not that you were suggesting that we ought to be cutting down forests in order to sequester carbon, though that argument really is made from time to time, and I thought I should just mention it.)
Posted by: Clark Williams-Derry | Jun 2, 2005 2:16:53 PM
There is no doubt that many forests will benefit from thinning because of a century of fire suppression. If you hike in the area, you have seen second growth forests in desperate need of thinning. It also is obvious that properly managed biomass energy is a responsible renewable energy alternative. (Or supplement in the case of co-fired coal/wood energy)
The problems come during the implementation. Will thinning turn into clear-cuts? Will the primarily fossil energy used during harvest and transportation of the wood be offset by the energy from burning the wood? Are the harvesting techniques sound? Will there even be any companies willing to bid on thinning projects?
This concept deserves further study. There are many potential environmental as well as economic benefits to be had here – If only somebody can work through all of these issues.
Posted by: Matt Leber | Jun 3, 2005 8:26:09 AM
Clark - thanks for the clarifications. Valuable information.
I try and take into acount a balance of energy concerns with environmental concerns, and in kneejerk fashion I get irritated when people propose using trees as feedstock.
On the other hand, the carbon cycle by itself is pretty darn flexible. It is just the confluence of burning ALL the fossil fuels and THEN setting sights on trees that bugs me.
Upon reflection, I am fine with using things like switchgrass and sawdust as feedstock for biofuels, but I am emphatically against deforestation to keep the SUV's rolling.
It is a fine line.
Posted by: Jon S. | Jun 3, 2005 7:28:29 PM
"Thinning" the forest and using the product of that "thinning" to make biofuels OR burning it to make steam to make electricity is STILL turning the forest into an unnatural state and inviting mudslides and/or monoculture, isn't it? I mean, where is the positive aspect?
Posted by: Joe | Jun 4, 2005 10:10:19 AM
"Thinning" the forest and using the product of that "thinning" to make biofuels OR burning it to make steam to make electricity is STILL turning the forest into an unnatural state and inviting mudslides and/or monoculture, isn't it?"
Not really. The low value of biomass fuel makes the environmental effects pretty benign. The market won't support road construction, so it is limited to already roaded areas, usually second growth natural reproduction or plantations. The logging technology that is efficient enough to make biomass logging cost-effective works only on ground that is close to flat. There is nothing in biomass thinning that inherently favors monoculture. If a pine or Douglas-fir plantation is thinned, the more open stand that results will be more favorable to the development of an understory of shade tolerant species. Most foresters recognize that mixed stands are less susceptible to catastrophic insect infestations, and will emphasize the need to maintain the minor species.
I did some rough calculations once on the gas I put in my pickup to get firewood versus the fossil fuel I don't use for home heating, and it was about a 20 to 1 benefit.
Posted by: sf | Jun 4, 2005 9:10:12 PM
When Joe writes,
"'Thinning' the forest ... is STILL turning the forest into an unnatural state..."
it raises the question of what is "natural" without defining it.
Sidestepping that philosophical discussion, I would argue that proper thinning likely steers the forest toward a state that more closely approximates its pre-industrial condition. There used to be more frequent, lighter fires than there have been during the last century of fire suppression. So I suspect that a forest where some of the smaller trees are thinned out is closer than the forests we see today to the landscape that greeted the first European explorers in these parts.
Matt makes a key point, though: many demons can inhabit the details of these thinning projects. Such timber sales need to be watchdogged to make sure they don't become excuses for clearcutting or high-grading (skimming off the best trees).
Posted by: Seth Zuckerman | Jun 5, 2005 11:50:17 PM
Well, 'the landscape that greeted the first European explorers' had been fire-managed by native humans, although that was ignored for a long time.
I suspect the traditional charcoal-burners (of Europe) turned forest small-stuff into sustainable fuel. Not so much fuel, and they were miserably poor, but there is precedent.
Posted by: clew | Jun 14, 2005 4:55:03 PM