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 Plant Hormone Makes Space Farming a Possibility
17.10.2018 | Universität Zürich

nachricht Goldilocks principle in biology -- fine-tuning the 'just right' signal load
15.10.2018 | Aarhus University

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: Goodbye, silicon? On the way to new electronic materials with metal-organic networks

Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz (Germany) together with scientists from Dresden, Leipzig, Sofia (Bulgaria) and Madrid (Spain) have now developed and characterized a novel, metal-organic material which displays electrical properties mimicking those of highly crystalline silicon. The material which can easily be fabricated at room temperature could serve as a replacement for expensive conventional inorganic materials used in optoelectronics.

Silicon, a so called semiconductor, is currently widely employed for the development of components such as solar cells, LEDs or computer chips. High purity...

Im Focus: Storage & Transport of highly volatile Gases made safer & cheaper by the use of “Kinetic Trapping"

Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles

Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...

Im Focus: Disrupting crystalline order to restore superfluidity

When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.

We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...

Im Focus: Micro energy harvesters for the Internet of Things

Fraunhofer IWS Dresden scientists print electronic layers with polymer ink

Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...

Im Focus: Dynamik einzelner Proteine

Neue Messmethode erlaubt es Forschenden, die Bewegung von Molekülen lange und genau zu verfolgen

Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Conference to pave the way for new therapies

17.10.2018 | Event News

Berlin5GWeek: Private industrial networks and temporary 5G connectivity islands

16.10.2018 | Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

 
Latest News

Mineral discoveries in the Galapagos Islands pose a puzzle as to their formation and origin

19.10.2018 | Earth Sciences

Less animal experiments on the horizon: Multi-organ chip awarded

19.10.2018 | Life Sciences

New method uses just a drop of blood to monitor lung cancer treatment

19.10.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>