Gothenburg, Sweden 2017

Understanding the Climate Effects of Bioenergy Systems

16 May 2017, Chalmers University, Gothenburg, Sweden

Co-hosted by: IEA Bioenergy Task 38 and Chalmers University of Technology

Objectives

The objectives for the workshop are to advance scientific understanding of the climate effects of bioenergy, particularly with respect to:

• Significance of timing of carbon emissions and sequestration associated with bioenergy systems
• What insights does climate science provide concerning bioenergy in the context of temperature targets, carbon budget / emission space, timing of peak emissions and peak warming
• How bioenergy contributes to transformation pathways
• Modelling and assessment of bioenergy with carbon capture and storage (BECCS)
• Roles of life cycle assessment, energy system modelling, and climate science in informing policy development for bioenergy

Bioenergy based on woody biomass from existing forests may most often be the “study object” in this workshop, but these topics listed are valid also for other bioenergy systems. The focus will be on scientific and technical issues, and how to derive advice for policy-makers. We aim to facilitate dialogue between scientists, to clarify divergent views on the role of forest-based bioenergy in climate change mitigation, and to identify research needs to fill knowledge gaps.

Background

Bioenergy has been promoted as a renewable, low carbon energy source. However, the climate effects of bioenergy have been questioned by various authors over the last decade. Further, there is disagreement on the appropriate methods for quantifying the impacts of bioenergy on climate change.

Recently, the debate has been rekindled through the publication of a report by Chatham House “Woody Biomass for Power and Heat: Impacts on the Global Climate”. Members of IEA Bioenergy wrote a critique, and others contributed to the debate:; Agostini et al.; Finnish scientists; FutureMetrics; Glen Peters; UK Renewable Energy Association; US/EUR scientists.

The focus of the recent discussion is the use of woody biomass from existing forests, with particular attention on wood pellets sourced from USA and transported to Europe for generation of electricity. Key issues raised include:

• How bioenergy contributes to the global carbon budget
• Impact of bioenergy on energy system transformation
• Short-term vs long-term emissions reduction targets
• How climate effects of bioenergy should be evaluated
• How bioenergy affects the forest carbon sink
• How forest management and market forces influence the climate effects of bioenergy.

This workshop builds upon a series of previous expert meetings organised by various IEA Bioenergy Tasks to discuss the use of forest bioenergy and its impact on climate change¹, and previously published documents such as the “IEA Bioenergy ExCo statement on the effects of timing of emissions”².

This expert meeting aims at clarifying issues raised during the recent debate on climate effects of bioenergy, with particular attention to methodological aspects.

Recommended reading

1. Chatham House report “Woody Biomass for Power and Heat: Impacts on the Global Climate” – especially Chapters 1 and 2
2. IEA Bioenergy response to Chatham House report: http://www.ieabioenergy.com/wp-content/uploads/2017/03/Chatham_House_response_supporting-doc.pdf and other responses listed in Background
3. IPCC AR5 WGIII Chapter 6 Assessing Transformation Pathways: https://www.ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_ar5_chapter6.pdf
4. IPCC AR5 WGIII Chapter 11 Agriculture, Forestry and Other Land Use (AFOLU) Appendix on Bioenergy, p870 http://ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_ar5_chapter11.pdf
5. For a quick overview of items 3 and 4, read Section 4 of the WGIII SPM: http://ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_ar5_summary-for-policymakers.pdf
6. European Forest Institute report: “Forest biomass, carbon neutrality and climate change mitigation” (Berndes, Asikainen, Cowie, Egnell, and others)
   Full report: http://www.efi.int/files/attachments/publications/efi_fstp_3_2016.pdf

Workshop Program

Participants