Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Carbon mitigation strategy uses wood for buildings first, bioenergy second

23.11.2011
Proposals to remove the carbon dioxide caused by burning fossil fuel from the atmosphere include letting commercially managed forests grow longer between harvests or not cutting them at all.

An article published in the journal Forests says, however, that Pacific Northwest trees grown and harvested sustainably, such as every 45 years, can both remove existing carbon dioxide from the air and help keep the gas from entering the atmosphere in the first place.

That's provided wood is used primarily for such things as building materials instead of cement and steel – which require more fossil fuels in their manufacture – and secondarily that wood wastes are used for biofuels to displace the use of fossil fuels.

"When it comes to keeping carbon dioxide out of the atmosphere, it makes more sense to use trees to recycle as much carbon as we can and offset the burning of fossil fuel than it does to store carbon in standing forests and continuing burning fossil fuels," said Bruce Lippke, University of Washington professor emeritus of forest resources.

Lippke is one of eight co-authors of the article in Forests. It is the first to comprehensively calculate using woody biomass for bioenergy in addition to using wood for long-lived products. The article focuses on the extra carbon savings that can be squeezed from harvesting trees if wood not suitable for long-term building materials is used for bioenergy. Such wood can come from the branches and other debris left after harvesting, materials thinned from stands or from plantations of fast-growing trees like willow.

For the article, the co-authors looked at selected bioenergy scenarios using wood from the U.S. Pacific Northwest, Southeast and Northeast.

They considered two ways of producing ethanol from woody biomass – gasification and fermentation – and used what's called life cycle analysis to tally all the environmental effects of gathering, processing and using the resulting fuels. Ethanol from woody biomass emits less greenhouse gas than an equivalent amount of gasoline, between 70 percent and a little over 100 percent less.

How much of a reduction depends on the process. Achieving slightly more than a 100 percent reduction in greenhouse gas emissions is possible, for example, using a fermentation process that both produces ethanol and generates enough electricity to offset the fossil fuel used in the fermentation process.

In contrast, producing and using corn ethanol to displace gasoline reduces greenhouse gas emissions 22 percent on average, according to the Environmental Protection Agency's fact sheet "Greenhouse Gas Impacts of Expanded Renewable and Alternative Fuels Use."

While biofuels from woody biomass are carbon friendly, Lippke cautions that the U.S. should not use tax breaks or other incentives that inadvertently divert wood to bioenergy that is better used for long-lived building materials and furniture.

"Substituting wood for non-wood building materials can displace far more carbon emissions than using the wood for biofuel," the article says. "This fact creates a hierarchy of wood uses that can provide the greatest carbon mitigation for each source of supply."

Lippke said using wood for products and bioenergy can be considered carbon neutral because the carbon dioxide trees absorb while growing eventually goes back to the atmosphere when, for instance, wood rots after building demolition or cars burn ethanol made from woody debris. With sustainably managed forests, that carbon dioxide is then absorbed by the growing trees awaiting the next harvest.

The co-authors aren't advocating that all forests be harvested, just the ones designated to help counter carbon dioxide in the atmosphere. Older forests, for instance, provide ecological values even though they absorb less carbon dioxide as they age.

In the article the authors also urge policymakers and citizens to consider not just carbon mitigation but also to find ways to weigh the importance of energy independence from fossil fuels when considering how to use woody biomass for bioenergy.

"Simply burning woody biomass to generate heat or electricity makes sense for carbon mitigation," he says, "But there's no energy independence gained," Lippke said. So carbon efficiency is only one part of the equation. Transportation fuels depend heavily on imported oil and therefore biofuels that replace them make additional contributions to the domestic economy, including energy independence and rural economic development, the authors said.

Other co-authors are Richard Gustafson and Elaine Oneil with the UW, Richard Venditti with North Carolina State University, Timothy Volk with the State University of New York, Leonard Johnson with the University of Idaho, Maureen Puettmann of WoodLife Environmental Consultants and Phillip Steele with Mississippi State University.

The publication integrates findings across many previous reports generated by a consortium of 17 research institutions that have been involved in life cycle analysis of wood products for more than 15 years through the Consortium for Research on Renewable Industrial Materials, based at the UW. The recent biofuel life cycle research was funded with a grant from the U.S. Forest Service's Forest Products Laboratory.

For more information:

Lippke, 206-322-8205, office 206-543-8684, cell 206-931-7297, blippke@uw.edu

Oneil, UW faculty and executive director CORRIM, office 206-543-8684, eoneil@uw.edu

Gustafson, UW faculty, advanced biofuels such as ethanol from cellulose, 206-543-2790, pulp@uw.edu

Puettmann, CORRIM's consultant for reviewing life cycle data, 541-231-2627, maureen.puettmann@q.com

Suggested websites

Abstract and link to pdf of article http://www.mdpi.com/1999-4907/2/4/861/

Bruce Lippke http://www.cfr.washington.edu/SFRPublic/People/FacultyProfile.aspx?PID=11

EPA fact sheet "Greenhouse Gas Impacts of Expanded Renewable and Alternative Fuels Use" http://tinyurl.com/EPAFactSheetAltFuels

Consortium for Research on Renewable Industrial Materials http://www.corrim.org/

Sandra Hines | EurekAlert!
Further information:
http://www.uw.edu

More articles from Agricultural and Forestry Science:

nachricht The inner struggle of the evening primrose: Chloroplasts are caught up in an evolutionary arms race
14.03.2019 | Max-Planck-Institut für Molekulare Pflanzenphysiologie

nachricht Cereals use chemical defenses in a multifunctional manner against different herbivores
06.12.2018 | Max-Planck-Institut für chemische Ökologie

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

Im Focus: Revealing the secret of the vacuum for the first time

New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum

For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...

Im Focus: Sussex scientists one step closer to a clock that could replace GPS and Galileo

Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock

Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Molecular motors run in unison in a metal-organic framework

20.03.2019 | Life Sciences

Active substance from plant slows down aggressive eye cancer

20.03.2019 | Life Sciences

Novel sensor system improves reliability of high-temperature humidity measurements

20.03.2019 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>