A new study was just published by the University of Idaho thoroughly debunking the flawed Manomet Biomass Study.
The full report is here: http://www.cnrhome.uidaho.edu/documents ... 9711&doc=1
Here are some excerpts with some commentary:
Accounting for Greenhouse Gas Emissions from Wood Bioenergy
Response to the U.S. Environmental Protection Agency’s Call for Information, Including Partial Review of the Manomet Center for Conservation Sciences’ Biomass Sustainability and Carbon Policy Study
by Jay O’Laughlin
Professor of Forestry and Policy Sciences
Director of the College of Natural Resources Policy Analysis Group
University of Idaho
Peer review of PAG work is absolutely essential for ensuring not only technical accuracy but also impartiality and fairness. That's great but why hasn't the Manomet Study been peer reviewed?
The utilization of woody biomass to produce energy is accompanied by concerns about sustainable forest management and greenhouse gas (GHG) emissions from burning biomass.
A novel (debt & dividend) approach is presented in the Biomass Sustainability and Carbon Policy Study commissioned by the Massachusetts Department of Energy Resources and conducted by the Manomet Center for Conservation Sciences.
The “debt-then-dividend” model is flawed by time and space restrictions. The carbon cycle does not begin at the time a tree dies, rather it is continuous; wood utilization requires many, many stands sustained over a long period of time, not one stand over four decades as in the Manomet Center study report. The study report also purposely ignores wood products carbon pools and the benefit of avoided GHG emissions from substituting wood products for concrete and steel, which consume large amounts of fossil fuel energy in their production. The benefit of wood substitution is that fossil fuels stay in the ground, and their emissions are avoided.
Although the Manomet Center study report recognizes that “all bioenergy technologies―even biomass electric power compared to natural gas electric―look favorable when biomass ‘wastewood’ is compared to fossil fuel alternatives” , analysis focuses on whole-tree biomass harvesting. The report perplexingly claims that until trees regrow and recapture carbon from the atmosphere, coal is a better choice than wood for producing electricity. The study report also rejects the accepted convention that burning biomass to create energy results in a zero net GHG emissions increase; i.e., the rest of the world considers bioenergy is a low-carbon source of renewable energy, but the Manomet Center report does not.
Not only did Manomet reject accepted convention, but they only looked at one part of the equation!
The buildup of atmospheric carbon problem is a long-term problem, so a long-term sustainable approach is appropriate; a short-term measurement of stack emissions approach is not. A definitive life-cycle analysis would help identify environmental tradeoffs as policymakers sort through the alternatives for future energy production.
One approach is to have facilities that burn biomass to produce energy report how much biomass they burn, and where the biomass comes from. If it is from mill residues or forest residues (i.e., logging slash or pre-commercial thinnings with no value as wood products feedstocks) then there is no reason to “cap” these emissions as these biomass sources would otherwise release carbon into the atmosphere in the near future anyway.
EXACTLY! So we don't need any regulations!
Box 1 identifies points that policymakers should keep in front of them while considering what to do about bioenergy emissions.
Some Things about Forest Carbon Accounting Policymakers Need to Know
1. Trees and other plants absorb (uptake) CO2 from the atmosphere.
2. Young trees grow faster and uptake CO2 more rapidly than old trees.
3. Old trees store more carbon than young trees, simply because they are larger.
4. Trees die and return stored carbon to the atmosphere.
5. Wood products store carbon for some period of time, and many displace concrete and steel products that in manufacturing require large quantities of fossil fuels.
6. Bioenergy is a renewable substitute for fossil fuels that also can help improve forest conditions and provide employment in rural communities.
In 2008, the Massachusetts Woody Biomass Energy report stated that “Burning fossil fuels releases ‘new’ carbon into the atmosphere that has been stored underground for millions of years. Burning biomass releases carbon that was recently absorbed from the atmosphere by a growing plant” (Urquart and Boyce 2008). In 2010, the Biomass Sustainability and Carbon Policy Study report conducted by the Manomet Center for Conservation Sciences (MCCS 2010a) for the Massachusetts Department of Energy Resources tried to develop a new way of thinking about wood bioenergy and the carbon cycle by analyzing a single forest stand over a period of decades, which is considerably less than the life of a tree. The Manomet Center’s contribution is a biomass carbon “debt-then-dividend” model. Their approach overlooks items 2, 4 and 5 in Box 1, and builds a case against item number 6, using wood bioenergy to substitute for fossil fuels because of short-term effects. It's obvious that Manomet had some built in biases against forest biomass harvesting for some unknown reasons.
Renewable portfolio standards (RPS) are policies that 36 states have adopted that require various changes in energy sources (DSIRE 2010). An RPS can increase pressure on utilities to consider biopower. Massachusetts is one such state, and its 2008 report on Woody Biomass Energy drew a distinction between fossil fuel emissions and biogenic emissions: “Burning fossil fuels releases ‘new’ carbon into the atmosphere that has been stored underground for millions of years. Burning biomass releases carbon that was recently absorbed from the atmosphere by a growing plant” (Urquart and Boyce 2008).
The Manomet Center study report misinterpreted what “carbon neutral” actually means with a statement that “. . . policies encouraging the development of forest biomass energy have generally adopted a view of biomass as a carbon neutral energy source because the carbon
emissions were considered part of a natural cycle in which growing forests over time would recapture the carbon emitted by wood-burning energy facilities” (MCCS 2010a, p. 6). To the contrary, the USDOE and EPA consider emissions from biomass to be zero because biomass combustion does not add new carbon to the atmosphere, not because after some period of time forests will recapture CO2.
Is MA State Government bipolar? First they come out with a report that supports biomass then they come out with a report that says it is supposedly worse than coal! Management of multiple-product forests can help maintain and improve the overall carbon balance.
How can forest management help reduce atmospheric CO2? The EPA and resource management agencies should be focused on developing a consistent and logical rationale. In some respects this question is more important than the “carbon neutral” question, because forests can help reduce the amount of CO2 already in the atmosphere. Five forestry strategies can affect climate change. In order of their relative importance these are 1) reduce stand-replacing fires; 2) keep forestlands in forests; 3) afforestation and reforestation; 4) use wood products as substitutes for fossil fuel-intensive products; and 5) forest management and rotation length (Cloughesy 2006). Any effort to significantly reduce wildfires will generate large volumes of biomass and require the development of an additional workforce (USFS 2005).
A science synthesis report on forests and carbon by the Ecological Society of America identified eight strategies for managing forests to enhance their role in carbon management. Avoiding deforestation is at the top of the list. Biomass energy and use of wood products in place of concrete or steel are two viable strategies (Ryan et al. 2010). According to the scientists who wrote the forestry chapter in IPCC report on climate change mitigation strategies, “In the long term, a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained yield of timber, fiber or energy from the forest, will generate the largest sustained mitigation benefit.”
Right just as Harvard Forest says, deforestation is the number one problem followed by destructive highgrading.
The “carbon debt-then-dividend” conceptual model used in the Manomet Center study report is problematic for four reasons:
1) the choice of today as the beginning time frame for carbon cycling instead of in the past when the existing forest began to uptake atmospheric CO2;
2) use of stand-level instead of the landscape-level modeling―“management actions should be examined for large areas and long time periods” (Ryan et al. 2010, p. 4);
3) failing to use a life-cycle approach that includes emissions from transporting energy feedstocks; and
4) failing to include the carbon sequestered in wood products that result from the timber harvest “business as usual” scenario, and the avoided fossil fuel emissions from substitution for concrete and steel products in the analysis.
The Manomet Center study report short changes policymakers by focusing primarily on analysis of GHG emissions, using a novel model designed to replace the long-established principle that biomass combustion results in a zero net emissions increase because it is part of
the continuously ongoing carbon cycle. In so doing the Manomet Center study report treats biomass as if it were mined like fossil fuels, until sometime in the future when the biomass has regrown and repaid its “carbon debt.” In reality, that “debt” is imaginary because biomass was produced by the carbon cycle and will be replaced by it unless deforestation occurs.
Furthermore, the use of wood products that replace concrete and steel immediately produces the benefit of a permanent reduction in GHG emissions much greater than the “biomass carbon debt.” In addition, by selecting a small area to analyze, the model ignores the fact that adjacent vegetation will immediately reabsorb the carbon emitted to the atmosphere from dead vegetation, whether death is the result of harvesting biomass to make wood products or energy, or from fire, insects and disease.
The idea that the combustion of coal is somehow better for the atmosphere than the combustion of wood for bioenergy as currently practiced in the U.S. does not make sense. The current debate is likely to conclude that burning wood to produce electricity is an improvement over burning coal, now, but only if the feedstock comes from sustainably managed forests. The reason is not so much that biomass combustion result in a zero net emissions increase― although this is a valid argument because the carbon cycle is a continuous process―but rather because the bioenergy industry consumes “waste wood” residues that otherwise have no use and will be returned to the atmosphere in a short period of time anyway. This approach is strongly supported in the literature cited herein, including the Manomet Center study report.
Logging residues are a substantial underutilized resource that enlightened forest and energy policy could convert from a liability to an asset. Improving the condition of forests in many areas of the nation would involve thinning overly dense forests and salvage of dead timber. These materials could be used as energy feedstocks. The policy question is not whether wood bioenergy emits more CO2 than coal, but whether it makes sense to enable and facilitate use of biomass produced by the carbon cycle to substitute for fossil fuels, or encumber such use and continue to mine fossil fuels while allowing forests to decay and burn.
The coal fired power plants in Massachusetts get their coal from West Virginia where mountain top removal mining has been totally devastating. In addition, coal gives off far more serious pollutants. So how can utilizing renewable biomass be worse than coal as Manomet suggested?!
So the question is why is the MA DOER basing their proposed new biomass regulations on a study that has been so thouroughly discredited?
All of the proposed biomass regulations - http://www.mass.gov/Eoeea/docs/doer/ren ... %20SoS.PDF need to be rejected and thrown out. Otherwise, we foresters will be unable to do the necessary forest improvement work on 2 million acres of private forest land that is so desperately needed here in Massachusetts.
Mike Leonard, Consulting Forester
North Quabbin Forestry - http://www.northquabbinforestry.com
35 Leighton Road
Petersham, MA 01366