Life Cycle Assessment of Wood Energy Services on a Regional Scale: Methodological Development and Case Study Application

Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt Lehrstuhl für Holzwissenschaft Life Cycle Assessment of Wood Energy Services on a Regional Scale: Methodological Development and Case Study Application Christian M. Wolf Vollständiger Abdruck der von der Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt der Technischen Universität München zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. nat.) genehmigten Dissertation. Vorsitzende(r): Prof. Dr. J. Philipp Benz Prüfer der Dissertation: 1. Prof. Dr. Klaus Richter 2. apl. Prof. Dr. Gabriele Weber-Blaschke 3. Prof. Dr. Stefanie Hellweg (Eidgenössische Technische Hochschule Zürich) Die Dissertation wurde am 22.12.2016 bei der Technischen Universität München eingereicht und durch die Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt am 31.05.2017 angenommen. Acknowledgements______________________________ During the last four years, I was fortunate enough to meet a multitude of inspiring people that were of great support towards this work. For creating exceptional conditions both in respect to the working environment as well as the support during the PHD phase, I would like to thank Prof. Dr. Klaus Richter (TUM). I would like to thank Prof. Dr. Stefan Pelz (HFR) who is responsible for nurturing the idea of pursuing a PHD study in the first place. As such, he was of valuable aid towards the final decision of pursuing a PHD study and, furthermore during the PHD phase, as my graduate school mentor. I would like to express my deepest gratitude to Prof. Dr. Gabriele Weber-Blaschke (TUM) for being an awesome head of the material flow management group, in which I had the privilege of working and writing this dissertation, and for creating very favorable conditions towards the project and dissertation work. Her tireless and devoted attitude, as well as her personal interest in all things concerning sustainability and the success of the members of her working group was a great assistance towards the delivery of quality outcomes in respect to the project ExpRessBio, the publications which were created together as well as towards this dissertation. Furthermore, her commitment created a very positive working environment where it was easy to get together with the members of the working group and contemplate complex LCA problems. These brainstorming sessions are often the key to successful LCA, since almost all practitioners are faced with the same questions at some point in their career. In this respect I would also like to thank Karin Höglmeier greatly for the many discussions and the pleasant company while sharing an office. And I would also like to say sorry for letting your plants die. Furthermore, this work greatly benefited from the contributions of several master and bachelor students, to whom I wish the best in their future activities. These students are: Bettina Joa, Amrei Weber, Florian Krause, Fabian Bosch and Maren Herter. One of the biggest thanks has to be given to Dr. Daniel Klein (LWF) who, as a colleague working on the ExpRessBio project, is responsible of shaping and enhancing much of the research presented in this dissertation. His patience and ability to tackle complex questions played an important role towards our work. Thank you also for the many great coffee break and travel discussions. The research presented in this dissertation was embedded in the project ExpRessBio (Expert Group on Resource Management in Bioenergy), funded by the Bavarian State Ministry for Food, Agriculture and Forestry (StMELF). The project has been an intense learning experience due to the complex and interdisciplinary nature of the many tackled III challenges. The project was successfully completed thanks to the colleagues from the Technology and Support Centre Straubing (TFZ), Dr. Edgar Remmele, Dr. Daniela Dressler and Karsten Engelmann, the Bavarian State Research Center for Agriculture (LFL), Dr. Matthias Effenberger, Dr. Mona Maze and Dr. Omar Hijazi, the Bavarian State Institute for Forestry (LWF), Dr. Christoph Schulz and Dr. Daniel Klein, the Science Center Straubing (WZS) and Weihenstephan-Triesdorf University of Applied Sciences (HSWT), Prof. Dr. Hubert Röder, Prof. Dr. Peter Zerle, Martina Serdjuk and André Tiemann and the Chair of Organic Agriculture and Agronomy (ÖLB), Prof. Dr. Kurt-Jürgen Hülsbergen, Taras Bryzinski and Tobias Böswirth. Further, I would like to thank the members of the newly founded Professorship for Wood Bioprocesses at TUM, Prof. Philipp Benz, Lara Hassan and Nils Thieme, for the many great lunch break distractions. Yet another thanks to Prof. Philipp Benz for agreeing to act as the chairman for the PHD commission and for Prof. Stefanie Hellweg (ETH), Prof. Gabriele Weber-Blaschke and Prof. Klaus Richter, as members of the examination board, for their supervision and review of this dissertation. Finally I would like to thank my wife Lisa and my parents Christa and Hannes for their invaluable support, for their constructive feedback and for their trust in my abilities before and during my PHD time. IV Abstract_______________________________________ This dissertation addresses the methodological development of tools for the reproducible assessment of environmental impacts of wood and wood energy and applies these methods onto heating in the case study region of Bavaria. Wood energy is a cornerstone in the satisfaction of past, present and future energy demands as well as the mitigation of climate change. As such, it plays a crucial role in a multitude of national and regional energy strategies. However, positive benefits in respect to climate change do not universally translate to other environmental impacts, such as e.g. the emission of particulate matter. As such, the majority of heating related particulate matter emissions in Bavaria are caused by the combustion of wood. Typically, the environmental impacts of products and services are analyzed through Life Cycle Assessments (LCA). For many products and services, standardized calculation approaches for LCA have already been introduced and adopted. For wood and wood energy LCAs, which have been carried out for more than 20 years, no such standardized approach has yet been implemented. Therefore, comparisons between individual studies are often impossible or inadvisable. However, comparable methods are required in order to identify the true magnitude of potential benefits and burdens associated with the use of wood for the provision of energy, as propagated by national and regional energy- and climate change strategies. To develop comparable and reproducible methods, two systematic reviews and consecutive meta-analyses concerned with the production of wood and the energetic utilization of wood were carried out and further defined in the ExpRessBio methods handbook. This handbook extends the methodological proposal developed by the two review studies. Based on the outcomes of these studies, among others, methodological provisions in respect to the description of system boundaries, the publication of parameters and results, the handling of co-products and the selection of appropriate environmental indicators were proposed. In order to evaluate the current and future role of wood heating, the most important utilization for energy wood in the case study area of Bavaria, a direct application of the developed methods was carried out in a subsequent step. The role of wood heating was assessed via Life Cycle Assessments of the current and future shares of all individual energy carriers utilized for the provision of heat in Bavaria, i.e. the Bavarian heating mix. To analyze the environmental effects of shifts in the heating mix, e.g. through polices, emission factors of the comprising energy carriers and the Bavarian heating mix as well as relevant substitution percentiles were determined. Analyses were carried out for the indicators of Global Warming (GWP), particulate matter emissions (PM), freshwater eutrophication (ET), V acidification (AC) and the non-renewable primary energy consumption (PE). In 2011 a total amount of 663.715 TJ of final energy was used for the provision of heat in Bavaria. Solid −1 biofuels exhibit the third largest share of 12.6%. In total 49.6 Mt CO2-eq. * yr (GW) and −1 14,555 t of PM2.5-eq. * yr (PM) were emitted for heating in Bavaria. Current policies entail −1 a GHG reduction potential of approx. 1 Mt CO2-eq. * yr (-2%) while increasing the amount of energy wood by 15%. The maximum, hypothetical share of solid biofuels for the heating mix cannot surpass 25%, while the climate change mitigation performance of the current −1 use of solid biofuels is approx. 6.4 Mt CO2-eq. * yr . GHG-emissions would be 13% higher and PM emissions 77% lower without this energetic use of wood. In order to identify mitigation potentials through wood heating, in a subsequent step, displacement factors for all assessed wood heating systems were determined and a transferable methodology for the calculation of displacement factors, which is adaptable to other regions, was proposed. Since the magnitude of mitigation benefits associated with wood use can vary greatly, depending on regional parameters such as e.g. the displaced fossil reference or heating mix, displacement factors, considering region-specific production conditions and substituted products are required when assessing the precise contribution of wood biomass towards the mitigation of environmental impacts. In order to showcase

Load more