10 Feb 2011

Growth of Wood Biomass Power Stokes Concern on Emissions

Across the U.S., companies are planning scores of projects to burn trees and wood waste to produce electricity, claiming such biomass plants can be carbon-neutral. But critics contend that combusting wood is not really a form of green energy and are urging a go-slow approach until clear guidelines can be established.
By dave levitan

It seems modest, as power plants go — a 29-megawatt facility, situated just north of the Vermont-Massachusetts line, that will burn woody biomass to generate enough power for 25,000 to 30,000 homes. But like many proposed plants in the recently reborn biomass power industry — a supposedly renewable and clean energy source — the Vermont project is encountering significant opposition.

“We live in a wooded, hilly part of New England, so it’s easy to sweep your arm around and say, ‘Look at all these trees. How can there not be enough biomass to operate this plant?’” says Charley Stevenson, co-director of a citizens group in the area that is opposing the plant. “But when you start to look at the scale of the proposed plant, the answer to that becomes less clear.”

The Pownal plant, one of two that Beaver Wood Energy has proposed in Vermont, faces the types of concerns confronting the entire industry. Biomass proponents have long claimed the power source can be carbon neutral — that the amount of carbon dioxide released into the atmosphere by burning trees and wood waste in a biomass plant will be offset by the growth of new trees to replace the old ones. However, evidence has accumulated that although biomass has the potential for some carbon benefit compared to fossil fuels, burning wood isn’t as simple a climate solution as many thought.

Combusting wood to produce heat and energy is not a new concept. In fact, whoever first rubbed two sticks together tens of thousands of years ago was an early biomass proponent. And biomass power plants are certainly not new — most of the several-hundred existing plants were built decades ago. But in recent years, as interest in renewable energy has grown, the industry has awakened and dozens, if not hundreds, of new plants have been proposed in the U.S. or are at some stage of a permitting process. Although some of the more intense battles over biomass power plants have taken place in New England, biomass projects are being proposed across the U.S., from the Pacific Northwest to the Southeast.

The awakening can be pegged directly to two developments: the growth of state renewable portfolio standards, which require that a certain percentage of a state’s electricity be generated by green energy, and federal policies that provide large incentives for renewable energy projects.
‘We’re giving huge subsidies and carbon credits for something that is not carbon neutral,’ says one expert.
Biomass is listed right alongside wind, solar, and other carbon-free power sources in various regulations, a fact that can be traced to a single questionable idea: that burning biomass for power generation is carbon neutral.

“People are waking up to the fact that this is not such a good deal,” says William Moomaw, director of the Center for International Environment and Resource Policy at Tufts University. “We could decide we’re going to do it, but right now we’re giving these huge subsidies and carbon credits for something that is not carbon neutral.”

Among the first to call attention to the problem of simply labeling it all carbon neutral was a paper in Science in 2009. The paper, written by Princeton University’s Timothy Searchinger and colleagues, pointed out that when all biomass is considered beneficial in carbon accounting terms, the economics tend to favor converting large amounts of land into forests planted solely to be cut down and burned, thus increasing CO2 emissions.

The only way that biomass achieves carbon neutrality is if growing forests sequester — that is, absorb from the atmosphere — as much or more carbon dioxide than is released in the burning process. If those forests get burned and none spring up to replace them, there is clearly a net addition of carbon to the atmosphere. And even if there is a one-to-one ratio of burned trees to growing trees, there is a timing problem. It takes only seconds to burn a tree’s worth of wood, and decades for that tree to grow back and sequester the same amount of carbon.

In fact, a study commissioned by the state of Massachusetts and conducted by the Massachusetts-based Manomet Center for Conservation Sciences suggested that for at least 30 years from the initial cutting of trees for
Biomass burning can approach carbon neutrality, if energy sources are restricted to waste wood products.
biomass, there is actually a “carbon debt” compared to the burning of coal. It is only after several decades of tree regrowth that biomass power can start to show an emissions advantage over the dirtiest of fuels.

Still, biomass burning can approach carbon neutrality if forests are carefully managed and biomass power sources are restricted to waste wood products and material that would otherwise decompose on the forest floor and emit greenhouse gases anyway.

Because of the confusion surrounding biomass’s carbon neutrality, the EPA last month announced a plan to defer for three years the greenhouse gas permitting requirements for biomass facilities, ostensibly to allow time for better research into the proper ways to use biomass. This comes at the start of the agency’s effort to regulate carbon emissions from large sources around the country, and biomass proponents are happy for the deferral.

The biomass power industry says it does not want to cut down whole trees — let alone whole forests — just to produce electricity. Instead, the power plants will use wood residues from paper and timber mills and woody waste taken from other forestry practices.

“We would never defend the proposition that it is carbon neutral to take an acre of trees, burn those trees in a boiler, and pave that acre over for a Walmart,” says Bob Cleaves, president of the Biomass Power Association.

Though Tufts’ Moomaw and other experts seem to agree that at its absolute best, practices involving waste wood probably come close to carbon neutrality, they disagree on whether enough of the waste exists.
The biomass power industry says it does not want to cut down whole trees just to produce electricity.
Mary Booth — a scientist who in 2009 helped found the Massachusetts Environmental Energy Alliance, which opposes biomass burning — says that Massachusetts has only about 100,000 green tons (meaning, with the substantial moisture content included in the weight) of woody waste material available for use each year. She says that an average biomass plant needs about 13,000 tons of wood to produce 1 megawatt of electricity for one year; with biomass plants that average about 40 to 50 megawatt capacities, the state would run out of megawatts quickly.

Take the proposed Pownal plant, as well as its sister plant in Fair Haven, Vermont. They each would need about 350,000 tons of wood annually to produce at the stated capacity of 29 megawatts. Thomas Emero, one of the founding partners of Beaver Wood Energy, says that analyses have shown that taking half of the available waste wood from forest floors within 50 miles of Pownal would be enough to power the plant. The waste — otherwise unusable tops of trees, branches, and the like — would be created by existing logging operations, though a small portion would be added from a wood pellet plant connected to the Pownal power generating station.

“Within that same 50-mile radius, tree growth exceeds harvest by 2.4 million tons per year,” Emero says. “If that isn’t sustainable, then I don’t know what is.”

With so many other plants proposed, though, opponents see the equations differently. “There is no way that they aren’t harvesting more trees that would not otherwise be harvested,” Booth says.

Elsewhere in New England, similar issues have arisen. One proposed plant in Berlin, New Hampshire, has seen substantial opposition from within its own industry. A number of existing, small biomass facilities have argued against the Laidlaw Energy Group’s proposal for a 65-megawatt plant because it would substantially raise fuel prices. In other words, there isn’t enough wood in the region to go around.

As a result of the Manomet and other studies, Massachusetts will become the first state to actually put restrictions on types of biomass that can be included under the renewable portfolio standard. The changes are not yet finalized, but the draft regulation would limit biomass fuel to “non-forest
Massachusetts will become the first state to put restrictions on types of biomass that can be included.
derived and forest derived residues, forest salvage, and energy crops.”

Some say, though, that Massachusetts could be setting a standard that limits even truly beneficial biomass utilization. “We do see a danger of throwing out the baby with the bathwater, because the draft regulation would essentially do away with stand-alone biopower facilities,” says John Rogers, a senior energy analyst with the Union of Concerned Scientists. “There's a concern, if we’re setting the bar too high, that we’re cutting out biomass resources that the science says can be beneficial.”

Yet with every state except Massachusetts still using a generic biomass definition that doesn’t set limits, there could be substantial dangers. Booth helped conduct a study with the Environmental Working Group that made some stark estimates: Given the relatively modest projected growth of wind and solar power in the near future, to generate 25 percent of all U.S. electricity from renewable sources by 2025 would require an increasing dependence on biomass, and subsequently the need to clear-cut 46,000 square miles of forests over the next 15 years. That’s an area bigger than Pennsylvania.

The rush of studies and research in the last several years highlights a growing understanding that one cannot simply build a biomass plant, throw some wood in the boiler, and claim to be saving the planet. There are, however, circumstances and specific places where it can be done well.

Renewable energy resources in the southeastern U.S. don’t compare with wind in the Midwest or solar resources in the Southwest. As a result, biomass has long been suggested as a potential renewable energy option in the South. And though the same caveats remain in terms of determining carbon neutrality, there are differences. For one, the warm Southeastern climate means trees will grow back faster, lessening the period before neutrality is achieved.

Still, opposition has arisen to some proposed biomass plants in the Southeast. One 40-megawatt plant proposed in Lowndes County, Georgia, is being challenged by local environmental groups concerned about where the wood will come from and local health impacts.

Biomass proponents contend that the EPA’s decision to defer greenhouse gas permitting regulations for biomass plants will give the industry time to prove its environmental worth.


Refilling the Carbon Sink:
Biochar’s Potential and Pitfalls

Refilling the Carbon Sink: Biochar’s Potential and Pitfalls
The idea of creating biochar by burning organic waste in oxygen-free chambers — and then burying it — is being touted as a way to cool the planet. But while it already is being produced on a small scale, biochar’s proponents and detractors are sharply divided over whether it can help slow global warming.
“I think it’s a good thing,” says Samuel Jackson, a biomass researcher at the University of Tennessee. “I think it will encourage industry investment and innovation in biomass utilization.” Jackson, who studies both woody biomass material as well as energy crops like switchgrass, is also involved with a startup biomass company called Genera Energy.

While some biomass energy skeptics, such as Booth and Moomaw, say the delay is political and a bad idea, other analysts are more optimistic about biomass’s potential.

“Biomass is a resource that can be tapped well or it is a resource that can be tapped badly, and we need policies that drive development of the good stuff but keep out the bad stuff,” says Rogers. “It can be done right, and we should find ways to do that, not just say no to it.”


Dave Levitan is a freelance journalist based in Philadelphia who writes about energy, the environment, and health. His articles have been published by Reuters, SolveClimate, IEEE Spectrum, and Psychology Today. In previous articles for Yale Environment 360, he wrote about the potential of vehicle-to-grid technology and whether biochar can help slow global warming.

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Scale is the key.

By some estimates, North Americans are consuming 50 percent more energy than that collected by all the biomass in North America.

We are only able to do this thanks to the use of ancient sunlight, banked during the Carboniferous Period. Unless you're a fan of nuclear energy, this is clearly unsustainable!

Before the widespread use of fossil fuel, New England was clear-cut for fuel. And there were 1/7th the number of people around then. People proudly say that forests have recovered from past abuses, but what will happen as fossil fuel declines if the forests are the back-up plan?

The answer is obvious, but unpalatable: we need to learn how to live on perhaps as little as 1/8th the energy we now use. Until we are able to cut back on energy use, we should not even be considering mowing down the forests for their energy.

Posted by Jan Steinman on 10 Feb 2011

I would like to know if high efficiency residential pellet boilers are a good approach to becoming carbon neutral. Any thoughts?

Posted by john roberts on 10 Feb 2011

Jan Steinman, I was with you until your last sentence. Just because biomass energy is complex and largely misunderstood does not mean we shouldn't do it.

The absolutist approach is unhelpful, given the magnitude of our climate crisis. I'd say the same thing to biopower industry proponents who claim that all biomass is carbon neutral. Not all biomass is good, not all bad. Good science must prevail.

From my view, the climate crisis demands that we use every tool in the kit, and figure out how to do biomass energy sustainably, and what level of utilization can benefit the climate. Current levels of woody biomass use for energy have continued for decades without "mowing down forests for their energy." See for example this 20 year old Craven County Wood Energy facility: I welcome anyone to show me documentation of harms imposed by this facility. (Seriously, I'm writing a case study on it, and I want to know what harms it may have caused, if any.)

The paramount question is How much can we expand biomass energy and it still remain beneficial for the climate?

The question demands using good science to determine actual carbon life-cycle impacts. More and better life-cycle analyses are needed on this paramount question. The challenge is, the answer will be different in every region of the country, depending on the kind of biomass (sawdust vs wood chips vs animal waste), how rapidly it is grown, and the efficiency of energy conversion (CHP vs simple boilers), among other variables.

Carbon life-cycle analysis is complex, but we have decades of LCA showing that biomass energy can help repair the damage done by coal. We cannot afford not to pursue it.

Posted by John Bonitz on 10 Feb 2011

Thanks for the article and the feature use of the proposed Beaver Wood biomass plant(s) in Pownal, VT -- which would be located 3 miles upwind from where I am writing this comment.

When I was a graduate student at Yale School of Forestry we spent a considerable amount of time investigating the myth of "waste wood" -- the tops and fine material residuals not suitable for forest products at that time. This "waste" contains about 80 percent of the above ground nutrient capital of the living biomass and therefore is not "waste" at all. It should be left in the woods to slowly return to the soil and then the next generations of living organisms that over the long haul are dependent upon the nutrients that it contains.

Posted by Hank Art on 10 Feb 2011

Now that Vermont has ruled out Biomass, nuclear (state senate voted to close Vermont Yankee), coal and natural gas from shale, what is left? Solar and wind aren't going to keep their lights on. Perhaps they are relying on wishful thinking. John Roberts is right. Science needs to prevail but sadly, this has no chance of happening in a country where high school physics and chemistry are no longer of interest to our children (or their parents).

Posted by Paul on 11 Feb 2011

When i see in france forests that are full of dead trees and people relying on oil at the exact same location to heat their houses, i think there is a problem.

Posted by kervennic on 11 Feb 2011

Ecosystems are being consumed by the profit motive all over the planet, palm oil for biodiesel, sugarcane and corn for ethanol, not to mention for food and fiber.

Government subsidies for biomass burning pours gas on that raging fire. That's the last thing we need. People cheat, politicians pander. Time to rethink nuclear: Google "Biodiversivist nuclear"

Posted by Russ Finley on 11 Feb 2011

Mr. Levitan has written a nice article showing the appalling lack of understanding in the academic and political communities of emerging and innovative gasification technologies. His article could have easily been a description of events 100 years ago. Most importantly with gasification of wastes there is no need to cut down and burn trees for power. However, there is a real need for clean renewable power, but more than sufficient supplies of biomass from all waste sources exists to meet this demand without cutting down trees.

The Solena Group has a plasma gasification system that obtains 2mw of renewable power from one ton of waste, not .5mwh from an incinerator and does not need trees. Thus, contrary to what is stated in this article, gasifying 58,000t/y would yied 56mwh. Solena's system produces no pollution, no ash, and low greenhouse gases--no SOX or particulate matter emissions. The community clearly does not understand what being carbon neutral means. Gasification plants are recycling biomass waste, so the plants CO2 emissions are carbon neutral. No fossil fuels are used, which would add new carbon. Other concerns not addressed are trees cut down to provide space for housing and retail companies, and the threats of forest fires and the beetle infestation of millions of acres of trees in the West.

Dennis Miller

Posted by Dennis Miller on 11 Feb 2011

As one of the authors of the Manomet study, I'd like to second the comments from John Bonitz. Based on what we learned in doing the work for Massachusetts, I think Bonitz gets it exactly right. Not all biomass is the same from a GHG perspective and we should be incentiving our use of it based on policies that promote those types of biomass energy that yield GHG benefits sooner (waste wood, thermal, and CHP).

Posted by Tom Walker on 11 Feb 2011

I'm sorry, but saying that burning wood is *not* carbon-neutral is insane!

If you let said trees stay in the woods, they eventually die and rot and release the same
amount of carbon into the atmosphere , EXACTLY the same, as if you burn the wood and capture the energy for heat! Yes of course there is a carbon debt delay, but the point is it WILL make up the difference eventually, which is MUCH MUCH better than releasing fossil-based carbon, which has been trapped for millennia, and is being released now, and will NEVER be put back in the bottle.

Every KW of energy we get from wood is one less KW that we DONT release from fossil
sources, and this is a VERY good thing.

I am convinced this is all spin from a lobby who do not want forests cut down and managed
wholesale in this way.


-- Stefan in Montreal

Posted by Stefan on 11 Feb 2011

In the hierarchy of pollutants, wood-burning is actually more harmful than coal-burning. considering that wood smoke is 12 times more carcinogenic than cigarette smoke and remains biologically active 40 times longer (EPA), I hardly think we should be encouraging this type of pollutant on a large scale. I don't see much discussion of soot, particulates, benzene, dioxin, etc. I agree with Jan Steinman: we need to reduce our use, on every level.

Posted by m power giacoletti on 11 Feb 2011

How come the need for economicly viable markets, for the trees that need to be removed in thinning in order to keep forest healthy and sequestering carbon for long term storage, whether that be as living trees, homes, flooring and furniture is not brought up in the biomass discussion?

Posted by Mike on 11 Feb 2011

References to a 2008 Manomet study claim “Wood Power Emits More Carbon than Coal” are without merit. Even the authors disagreed releasing clarifying statements that such claims in press reports were a misinterpretation of their study.

How could such a claim be true? Burning fossil fuels causes a one-way flow of carbon to the atmosphere from deep storage pools that are not being replaced. Biomass emissions derive from carbon that was removed from the atmosphere by growing trees. Whether they are burned or left to decay as they mature their carbon will be returned to the atmosphere, a two-way flow. Burning biomass for energy displaces fossil fuels reducing that one-way flow of carbon to the atmosphere.

The misinterpretation derives from comparing smokestack emissions rather than measuring life cycle impacts. Biomass is derived from sustainably managed forests that every year absorb as much carbon from the atmosphere as is returned by decay or removed for product uses. Using a renewable resource to produce building materials or biofuels substitutes for fossil intensive products and fuels, reducing the one way flow of fossil carbon that is contributing to greenhouse gas emissions. It is that simple. For details:

Posted by Bruce Lippke on 11 Feb 2011

Any biomass not grown from sunlight in the past twelve months is not applicable. Burning to produce a uniform "carbon" for landfill is clearly less efficient than burying it with the hydrogen still attached. Dig a hole to fill in a hole. Dig coal, bury carbon, non-sense.

The economy is messed up because the government got into spending future tax dollars today. There is no possible "investment" value in burning trees today so they can grow back later. Crop biomass with fast growing crops for burning might work, it won't work to make ethanol alone but maybe the combination could support some electricity at the potential expense of more starving people.

Posted by David Crosbie on 11 Feb 2011

With biomass we have the opportunity to be carbon negative instead of just carbon neutral or close to carbon neutral. If the biomass is cooked into biochar, most of the carbon could be sequestered and used to make soils more productive. The biogas produced in the process would be mostly hydrogen and could be used to produce electric power and/or heat or for transportation energy while releasing mostly water vapor and very little carbon dioxide.
While this technology may require some time for research and development, it might make sense to slow down on developing biomass burning plants so we could eventually use the biomass through biochar as a way or removing and sequestering carbon now in the atmosphere.

Posted by Joe Landis on 12 Feb 2011

Thank you very much for sharing interesting topic. You are giving very good stuff through this post. I will suggest my friends to read this post. Since the 1970's the scientific community has been interested in Converting Biomass To Energy.

In the beginning, there was not much interest as the world was getting along fine with fossil fuel. With the many scientists, throughout the world, working on this problem it is hoped that Converting Biomass To Energy on a large scale is not too far in the future. I have read more about Converting Biomass To Energy at What do you think?

Posted by Aisha Miller on 12 Feb 2011

Actively, well managed forests grow more than relatively unmanaged forests. The larger part of
forests I have seen in New England are passively managed.

Tree harvesting, by the way, is a primary tool for managing a forest.

Better markets enhance tree harvesting.

Posted by Bruno F. Fritschi on 12 Feb 2011

As another author of the Manomet study I would also like to congratulate author Bonitz on getting it right. Not all uses of biomass for energy are equal in their effect on climate change and we need to differentiatie and incentivize accordingly.The analysis of these effects are not always intuitive and discussions like this and hopefully the EPA process will shed some light. For example, Bonitz refers to biomass coming from a forest that might burn in the future as not being carbon neutral.

Part of the analysis we must do is to calculate whether using biomass now will give us a more favorable atmospheric carbon effect at points in the future and how important that effect is on our climate change goals. If a forest is destined to burn, or be cut down and paved over for development that becomes the business as usual scenerio we can compare to. That is why harvesting and converting to energy biomass that comes from a forest destined to someday be a Walmart or impacted by catastrophic wildfire may be a good climate mitigation proposition, simply because we are using for energy carbon that otherwise would be naturally emitted in a business as usual scenario.

This kind of policy must be linked in some meaningful way to an overall policy that maintains as much of our forest cover and the carbon sequestered in it as possible in a growing and developing society.

Posted by Bob Perschel on 13 Feb 2011

I agree with Hank Art in that the so called "waste" products that are found on the forest floor, although releasing carbon, are what provides the base for the entire ecosystem. "Harvesting" these would only bring about future harm and destabilize nutrient cycles. I'm sure there are better ways of developing methods of energy generation from biomass.

Posted by Ethan on 13 Feb 2011

I agree with those who claim burning wood is not carbon neutral, at least in the short term- but, those who make that claim emit vast amounts of carbon every time they drive their car and eat beef or fly in jets- so I don’t consider it fair to demand that wood should never be burned for energy, especially very efficient CHP systems- so I support CHP biomass systems if the wood comes from exemplary forestry.

And I also support moving ahead ASAP with solar and wind power, despite the fact that those energy sources are not great for “base load”- because their use will reduce the demand on base load, so they will lower the demand on fossil fuels.

Posted by Joe Zorzin on 14 Feb 2011

I read this and many articles along the same pathway with great interest. As a forester, I have a particular qualm with the article but as a westerner, I see that many folks along the eastern seaboard miss nearly the entire point.

First, as a forester, I bring to the arguement a basic fact of nature... trees grow and trees die! Given soil, air and nutrients, trees on their own accord, grow and as a result of this growth, sequester carbon. Trees, even those ancient forests we so appreciate have a limited lifespan. And eventually they die. Most trees die much sooner and release most but not all their carbon to the atmosphere. Where is the "hidden" carbon? The soil picks up carbon and stores it for a longer term and then loans it to the next generation of plants. In the West, this pleasant cycle has an unruly cousin namely fire! Fire changes the equation in moves carbon from both live plants and soil organic matter in great quantities into the atmosphere. Fire can convert 100,000 acres of tree, shrub, grass and soil organic matter carbon including ancient old growth into the atmospheric carbon particulates and CO2 in the matter of a month.

Sure, we are largely responsible for the massive buildup of fuels having opted for a German rather than an Indian ecological model. Now, we are trying to reverse trend and bring fire back into a crowded landscape. Without biomass energy plants, this is nearly impossible. We foresters need some sort of market for small diameter wood. The same folks who oppose biomass energy tend to oppose cutting larger trees to make a thinning project pay for itself. The housing market won't take it. The paper market cannot absorb the quantity available and biomass energy development is stuck in NIMBY wasteland.

So, is it really true that many people seem to prefer massive wildfires and smoke to small controlled burns and importing oil to using what we have sitting around. Why I ask? Is it really a quibble over biomass energy being absoultuely carbon neutral? Not really. I believe the root cause is that many people simply don't really believe that trees grow and tree die. And they don't believe that fire will re-make the landscape with our without our intervention. They don't seem to mind it when the Finns efficiently use biomass to reduce their dependence on petroleum. So, it must be a NIMBY lack of understanding of forest dynamics. I believe that the only way we can influence the future direction of our forests and limit the damage from landscape replacing wildfire in the West is to integrate biology and economics. And to date, we seem to be stuck in the past and not viewing the future.

Posted by Timothy Murphy, CF on 14 Feb 2011

I have to agree with Stefan in Montreal. Many are missing some basic science. If a forest can produce a sustainable yield of say 1/3 cord of merchantable timber a year, and you burn that to heat your home from your woodlot (as I do) then there is a net savings in terms of carbon emissions in that equivalent of fossil fuels had I been buring oil or natural gas. The same would be true for commerical forests where the timber was used for electricity production to offset coal. Clearly timber harvesting needs to be managed sustainably. You don't take take more off the land than the land can produce. No one is suggesting that we burn as much wood as fast as we can and then convert the land to another (non forest) land use.

The other important point here that seems neglected is that it is a good thing that there is a demand for forest products that is stronger than the demand for the use of that land for other purposes. If we recognize that commerical forests are valuable for biomass as wells as more traditional forest products that will increase the likelihood that they will remain forests and not be converted to other land usese that will premanently decrease their potential to sequester carbon dioxide.

Posted by Tom on 15 Feb 2011

You shouldn't confuse biomass supplies in small, crowded New England with what happens in the rest of the country. Elsewhere essentially all of the biomass fuel is obtained from waste sources, which clearly are carbon neutral.

Even the highly politicized Manomet study recognized this, though it was buried deep in the report in a single paragraph on p. 113.

Posted by Mike W. on 16 Feb 2011

The aspect missing from this article and most of the comments is that there are alternatives for use of forestry residues that based on life cycle analysis and assessment are better for the climate, emit less pollutants that are damaging to human health, are less damaging to ecosystems, and conserve more energy than combustion or integrated gasification-combustion. These include composting, processing into papermaking pulp, processing into engineered wood products, and alternative daily cover for landfills.

This result should not be surprising because it's the same life cycle assessment result one gets for virtually all waste materials - that's why recycling and composting are above disposal options such as waste-to-energy in the waste management hierarchy. Several peer-reviewed articles I've contributed show these results if the reader is interested (Morris, Journal of Hazardous Materials, 1996; Morris, International Journal of Life Cycle Assessment, 2005; Morris and Bagby, International Journal of Life Cycle Assessment, 2008; and Morris, Environmental Science and Technology, 2010). These articles and the life cycle assessment methodologies they use are applicable because stumps, branches, leaves and other biomass wastes are part of the municipal solid waste stream. Thus, life cycle analysis of the alternative uses for these components of solid waste yields the same relative results as for other components such as paper, cardboard, yard debris and food scraps.

The life cycle analysis work of Mark Jacobson from Stanford also shows that cellulosic based biofuels are worse for the climate and human health, and require more land use than truly renewable sources of energy such as solar and geothermal and even fossil fuel competitors such as petroleum and natural gas. (E.g., Jacobson, Energy and Environmental Science, 2009)

In short we should be subsidizing development of energy sources such as solar, wind and geothermal, not biomass based energy sources. On the waste management front we should be subsidizing recycling and composting, not waste-to-energy disposal.

Posted by Dr. Jeffrey Morris on 16 Feb 2011

Missing from the discussion so far is the link between biomass utilization, land conservation, and good forestry. The lack of steady markets for low-grade wood in New England puts landowners in a pickle: you can cut the trees that have value and leave the rest behind, or you can cut no trees, forego any revenue, and pay the property taxes altruistically. The former is classic high-grading, in which you cut the best, leave the rest, and degrade the genetic pool; the latter is the route to subdivision and land conversion.

Being able to sell low-grade wood for biomass, meanwhile, allows you to practice ecological forestry and manage for a wide variety of outcomes, from timber to wildlife to recreation, because you have a market for everything you cut. This also allows you to leave the tops and branches in the forest, where the nutrients belong. Long term, you end up with greater forest diversity and a lessened need to sell land to pay taxes.

Lest anyone fear that a move to biomass is going to denude New England, no state in the Northeast (except Maine, paper country) cuts even 50 percent of its annual net growth right now. Massachusetts cuts just 20 percent. Doubling our current biomass utilization wouldn't come close to eating up even our annual net growth. Talk of clear cutting Pennsylvania in order to fuel our biomass needs badly misrepresents both the way we actually manage our forests in the Northeast and distorts our capacity to do so.

Posted by Chuck Wooster on 17 Feb 2011

Here is where I find a few problems in this paper by Dave Levitan. The worst is using scientific sounding facts to drive what is a mostly emotional argument on his part.

The author finds a homeowner (probably led by a clear case of NIMBY) near a proposed biomass power plant to quote in this scientific sounding paper inferring “there can’t possibly be enough trees here” as an accepted scientific assessment of the available growing stock. Really Mr. Levitan - you could not bother to check the forest inventory data available in every state?

The author writes ‘We’re giving huge subsidies and carbon credits for something that is not carbon neutral,’ says one (unnamed) expert.” If the author was short of experts, here is a paper that cites over 100 PhDs who say it is carbon neutral.

The author also uses a visual statement that makes it sound like clearcutting 46 sq. miles over 15 years to generate 25% of our nation’s power is a horrible idea. Why did he choose 15 years? An annual number of 3,100 sq. miles/year or nearly 2,000,000 acres per year seems more intellectually relevant. It does not take much work by the author to make the number sound scary huge, but to be sure you get the point, he adds “That’s an area bigger than Pennsylvania.” (Note that had he used an annual figure, it would have been 1/15th the size of Pennsylvania, but that might not have been the visual to make his point.) The author also could have used the term “harvest” rather than emotional term “clearcutting” or could have at least mentioned that every acre would be required to be reforested each year. But the real question is whether this country has the growing capacity in our forests to harvest 2,000,000 acres each year for energy and sustain it along with other forest resources and products.

Here is one fact the author did not bother to add: We have about 750,000,000 acres of forest in USA. That is down from a billion acres in 1700, but is currently stable. So if the author was right on his facts, we would need to clearcut 0.2% of our forests each year to make 25% of all our electricity from renewable sources. If these forests were dedicated only to energy and grown on a 50 year cycle, we would need 10% of all of our nation’s forests dedicated to that cause. Very rudimentary calculations, the actual number may be less due to thinnings or longer based on the rotation cycle.)

Is it doable? Probably. Is it a big deal? Absolutely. Should it be done without thought? Never. But if in fact climate change is so dire that we need to do something or die, it seems like maybe getting 25% of all our electricity by burning renewable wood should get more of an analysis than this author or the NIMBY folks give it.

Finally neither this author nor the Manomet study really give any credence to the fact that storing carbon in trees for another 30 more years is only temporary until the wood rots. And every bit of coal burned in the meantime to keep carbon stored in wood is also directly additive to the atmosphere, but with no hope of being recycled within 30 years or even 3000 years.

The alternative is happening in the MN legislature this session as fission nuclear power plants are being given the green light. In my opinion that is a guaranteed 20,000 year long tragedy due to the poisonous waste its leaves for our children. That I think, is way, way worse than a “clearcut” near somebody’s vacation home in southern Vermont that would grow back in a couple of generations using carbon we burned today to make renewable energy.

Thomas Kroll
Land Manager and Arboretum Director
Saint John's Abbey and University
New Science Building 108
Collegeville, MN 56321-3000

Posted by Thomas Kroll on 25 Apr 2011

A lot of the analysis is too narrowly focused to be sufficient to make the best decision. A few additional issues worth mentioning: If the trees burn in wild or prescribed fires in the forest, they will release a more pollutants per unit mass then if burned in a high-efficiency waste to energy operation. On the other hand, transporting biomass to a facility costs $ & uses fossil fuels adding to pressure to overharvest (especially keeping nutrient recyclying needs in mind) locally. Mike Antal at the University of Hawaii has developed a portable, high-yield charcoal kiln that should be included in any biofuel assessment. Another option is co-firing where biomass is used to reduce fossil fuel use without needing to depend 100% on biomass. In any case, reduction in the use of technologies that may be more harmful than imperfect use of biomass (such as fracking) is important. Composting can also produce energy for low-grade uses like heating buildings and though it releases greenhouse gases, it doesn't generate particulate pollution, which is a health concern.

Ultimately, all forest-based energy schemes need to be compared to rapid-developments in algae-generated biofuels so that whatever makes the most sense in the big picture is promoted. Visually, natures method of converting sunlight to useable energy (e.g. a forest) is far more beautiful than an array of solar panels! The lightly-managed natural ecosystem also provides numerous other benefits (watershed protection, recreation, wildlife habitat) that solar cannot provide. The sensible course is broad assessment of all energy options and all their far-reaching impacts, followed by implementation of a few of the most-promising options on a modest scale ... and then learn as we go.

Bob Yokelson
Department of Chemistry
University of Montana

Posted by Bob Yokelson on 04 Feb 2012



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