Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Large differences in the climate impact of biofuels

16.11.2011
When biomass is combusted the carbon that once was bound in the growing tree is released into the atmosphere.

For this reason, bioenergy is often considered carbon dioxide neutral. Research at the University of Gothenburg, Sweden, however, shows that this is a simplification. The use of bioenergy may affect ecosystem carbon stocks, and it can take anything from 2 to 100 years for different biofuels to achieve carbon dioxide neutrality.

“Using a tree as biofuel creates a carbon dioxide debt that must be “paid back” before the fuel can be considered to be carbon dioxide neutral. Energy forest is fully neutralised after 3-5 years, while other trees grow so slowly that it can take up to 100 years before they achieve carbon dioxide neutrality” says Lars Zetterberg of the Department of Earth Sciences at the University of Gothenburg.

The use of bioenergy affects ecosystem carbon stocks over time in either a positive or negative way. Biofuels where the combustion related emissions are compensated rapidly have a lower climate impact than fuels for which it takes a long time for the emissions to be compensated. Despite this, the difference in climate impacts between slow and rapid biofuels is rarely highlighted in political contexts. Emissions from bioenergy are, for example, not included in countries’ commitments under the Kyoto Protocol.

In his PhD thesis, Lars Zetterberg analyses how different types of biofuels affects the ecosystem carbon stock over time, and the consequent climate impact. The results show that biofuels where the combustion related emissions are compensated rapidly have a lower climate impact than fuels for which it takes a long time for the emissions to be compensated. Results from this study can help decision makers to understand the climate impacts from different bioenergy types in order to prioritize between different bioenergy alternatives.

“The time perspective over which the analysis is done is crucial for the result. Over a 100 year perspective the use of stumps for energy has a significantly lower climate impact than coal, but over a 20 year time perspective, stumps have a higher climate impact than natural gas. Using logging residues in the form of branches and tops for energy reduces carbon dioxide emissions in both the short term and the long term.”

If environmental legislation, for instance the EU renewables directive, requires that climate benefits of biofuels are calculated over a 20 year period, biofuels that need longer time to reach carbon neutrality may be regarded as not renewable..

“If we want to do reduce global carbon emissions quickly, we should prioritize fuels that are beneficial on a short time scale, for instance 20 years In addition, over a longer time scale it will be beneficial to replace coal with stumps, even if we will not see a result until after 20 years.”

In the thesis, Lars Zetterberg also addresses how the EU Emissions Trading System should be designed in order to incentivize the use of carbon dioxide efficient fuels.

The thesis Instruments for Reaching Climate Objectives – Focusing on the Time Aspects of Bioenergy and Allocation Rules in the European Union’s Emissions Trading System was successfully defended at a disputation held in the Department of Earth Sciences at the University of Gothenburg.

For more information, please contact: Lars Zetterberg
Telephone: +46 8 5985 6357
E-mail: lars.zetterberg@ivl.se

Helena Aaberg | idw
Further information:
http://www.gu.se
http://gupea.ub.gu.se/handle/2077/26672

More articles from Ecology, The Environment and Conservation:

nachricht Waste in the water – New purification techniques for healthier aquatic ecosystems
24.07.2018 | Eberhard Karls Universität Tübingen

nachricht Plenty of habitat for bears in Europe
24.07.2018 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>