Synthetic Biology E-Book
78,99 €
Mehr erfahren.
- Herausgeber: Wiley-VCH
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
This is the only book to focus on industrial and environmental applications of synthetic biology, covering 17 of the most promising uses in the areas of biofuel, bioremediation and biomaterials. The contributions are written by experts from academia, non-profit organizations and industry, outlining not only the scientific basics but also the economic, environmental and ethical impact of the new technologies.
This makes it not only suitable as supplementary material for students but also the perfect companion for policy makers and funding agencies, if they are to make informed decisions about synthetic biology.
Largely coordinated by Markus Schmidt, a policy adviser, and the only European to testify in front of the bioethics commission of the Obama administration.
Sie lesen das E-Book in den Legimi-Apps auf:
Seitenzahl: 475
Veröffentlichungsjahr: 2012
Ähnliche
Table of Contents
Cover
Related Titles
Title page
Copyright page
List of Contributors
Short CV of Contributors
Preface
Acknowledgments
Executive Summary
Biofuels
Bioremediation
Biomaterials
Novel Developments in Synthetic Biology
Introduction
What Are Synthetic Biology Applications?
Which Synthetic Biology Applications Did We Consider?
Selecting and Assessing Synthetic Biology Applications
The Regulatory Context for Synthetic Biology
1 Biofuels
1.1 Biofuels in General
1.2 Ethanol
1.3 Non-ethanol Fuels
1.4 Algae-based Fuels
1.5 Hydrogen Production
1.6 Microbial Fuel Cells and Bio-photovoltaics
1.7 Recommendations for Biofuels
2 Bioremediation
2.1 Bioremediation in General
2.2 Detection of Environmental Pollutants (Biosensors)
2.3 Water Treatment
2.4 Water Desalination with Biomembranes
2.5 Soil and Groundwater Decontamination
2.6 Solid Waste Treatment
2.7 CO2 Recapturing
2.8 Recommendations for Bioremediation
3 Biomaterials
3.1 Biomaterials in General
3.2 Biopolymers/Plastics
3.3 Bulk Chemical Production
3.4 Fine Chemical Production
3.5 Cellulosomes
3.6 Recommendations for Biomaterials
4 Other Developments in Synthetic Biology
4.1 Protocells
4.2 Xenobiology
4.3 Recommendations for Protocells and Xenobiology
5 Regulatory Frameworks for Synthetic Biology
5.1 United States of America
5.2 Europe
5.3 China
Annex A: List of Biofuel Companies
Annex B: List of Bioremediation Companies
Index
Related Titles
Luisi, P. L., Chiarabelli, C. (eds.)
Chemical Synthetic Biology
2011
ISBN: 978-0-470-71397-6
Parry, S., Dupré, J. (eds.)
Nature After The Genome
2010
ISBN: 978-1-4443-3396-1
Vertes, A., Qureshi, N., Yukawa, H., Blaschek, H. (eds.)
Biomass to Biofuels
Strategies for Global Industries
2010
ISBN: 978-0-470-51312-5
Fu, P., Panke, S. (eds.)
Systems Biology and Synthetic Biology
2009
ISBN: 978-0-471-76778-7
Soetaert, W., Vandamme, E. (eds.)
Biofuels
2009
ISBN: 978-0-470-02674-8
The Editor
Dr. Markus Schmidt
Organisation for International Dialogue and Conflict Management
Kaiserstr. 50/6
1170 Vienna
Austria
Cover
Birgit Marie Schmidt MA (RCA)
London, UK
Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty can be created or extended by sales representatives or written sales materials. The Advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.
Library of Congress Card No.: applied for
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.
Bibliographic information published by the Deutsche Nationalbibliothek
The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at <http://dnb.d-nb.de>.
© 2012 Wiley-VCH Verlag & Co. KGaA Boschstr. 12, 69469 Weinheim, Germany
Wiley-Blackwell is an imprint of John Wiley & Sons, formed by the merger of Wiley’s global Scientific, Technical, and Medical business with Blackwell Publishing.
All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.
Typesetting Toppan Best-set Premedia Limited, Hong Kong
Cover Design Adam-Design, Weinheim, Germany
Print ISBN: 978-3-527-33183-3
ePDF ISBN: 978-3-527-65926-5
ePub ISBN: 978-3-527-65927-2
mobi ISBN: 978-3-527-65928-9
oBook ISBN: 978-3-527-65929-6
List of Contributors
Rachel Armstrong
Senior Lecturer, Research & Enterprise
School of Architecture & Construction
University of Greenwich
Avery Hill Campus, Mansion Site, Bexley Road, Eltham
London SE9 2PQ
UK
Shlomiya Bar-Yam
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Mark Bedau
Reed College
3203 SE Woodstock Blvd.
Portland, OR 97202
USA
Jennifer Byers-Corbin
Gryphon Scientific
6930 Carroll Ave, Suite 810
Takoma Park, MD 20912
USA
Rocco Casagrande
Gryphon Scientific
6930 Carroll Ave, Suite 810
Takoma Park, MD 20912
USA
Antoine Danchin
AMAbiotics SAS
Building G1, 2 rue Gaston Crémieux
91000 Evry
France
Florentine Eichler
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Zheng-Jun Guan
Chinese Academy of Sciences
Institute of Botany
20 Nanxincun, Xiangshan
100093 Beijing
China
Allen Lin
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Ismail Mahmutoglu
BAUER Umwelt GmbH
In der Scherau 1
86529 Schrobenhausen
Germany
Martin Österreicher
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Kenneth A. Oye
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Lei Pei
Organisation for International Dialogue and Conflict Management
Kaiserstr. 50/6
1070 Vienna
Austria
Manuel Porcar
Universitat de València
Biotechnology and Synthetic Biology
Institut Cavanilles de Biodiversitat i Biologia Evolutiva
46071 Valencia
Spain
Pernilla C. Regardh
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Vincent Schachter
Total Gas & Power
Research and Development
2, place Jean Miller – La Défense 6
92078 Paris La Défense Cedex
France
Markus Schmidt
Organisation for International Dialogue and Conflict Management
Kaiserstr. 50/6
1070 Vienna
Austria
and
Biofaction KG
Grundsteingasse 36/41
1160 Vienna
Austria
Helge Torgersen
Institute of Technology Assessment
Austrian Academy of Sciences
Strohgasse 45, 5
1030 Vienna
Austria
Ralph D. Turlington
Massachusetts Institute of Technology (MIT)
77 Massachusetts Ave., Building E40-437 Cambridge, MA 02139-4307
USA
Wei Wei
Chinese Academy of Sciences
Institute of Botany
20 Nanxincun, Xiangshan
100093 Beijing
China
Short CV of Contributors
Rachel Armstrong is a medical doctor with qualifications in general practice, a multi-media producer and an arts collaborator whose current research explores the possibilities of architectural design to create positive practices and mythologies about new technology. She is collaborating with international scientists and architects to explore cutting-edge, sustainable technologies by developing metabolic materials in an experimental setting.
Shlomiya Bar-Yam is a graduate student in the Technology and Policy Program at MIT. She is working on the environmental implications of synthetic biology in release contexts. She graduated from Brown University with a BSc in Biology with a focus in ecology, and she has worked on sustainability programs and at the New England Complex Systems Institute as a science writer.
Mark A. Bedau is an internationally recognized leader in the interdisciplinary study of complex adaptive systems. He co-founded and is currently COO of ProtoLife Srl in Venice, Italy. He also cofounded the European Centre for Living Technology (UNIVE), in Venice, Italy. He is Professor of Philosophy and Humanities at Reed College and visiting Professor at the European School of Molecular Medicine (Milan, Italy). He is internationally recognized as a uniquely qualified expert in the philosophical foundations of complex adaptive systems.
Jennifer Byers-Corbin is a health effects and medical countermeasure modeler at Gryphon Scientific. Dr. Corbin received her PhD in biomedical science from New York University. Since then, she has applied her training to the study and analysis of biosafety and security. She represents BARDA modeling on several working groups on a broad range of topics related to biodefense. Dr. Corbin is an able and effective leader who has served as principal investigator or task leader for multiple projects for United States government clients.
Rocco Casagrande (BA chemistry and biology, Cornell University; PhD experimental biology, MIT) is the Managing Director of Gryphon Scientific, LLC. Over the past several years, Dr. Casagrande led several projects related to weapons of mass destruction and science policy for various United States Federal and State agencies. These projects include WMD threat and risk assessments and biodefense system evaluations, technology assessment, modeling and technical guidance. From December 2002 to March 2003, Dr. Casagrande served as an UNMOVIC biological weapons inspector in Iraq where he obtained hands-on experience with chemical and biological agents.
Antoine Danchin is a French geneticist known for his research in several fields of biology. Originally he was trained as a mathematician at the Institut Henri Poincaré and as a physicist at the Ecole Polytechnique. He is the Chairman of the startup AMAbiotics, specialized in metabolic bioremediation and synthetic biology. He was the director of the Department Genomes and Genetics at the Institut Pasteur in Paris where he headed the Genetics of Bacterial Genomes Unit.
Florentine Eichler has a graduate degree in law from the University of Vienna, Austria. During her studies in Austria and the Netherlands she focused on medical law. She is currently a Research Associate at the MIT Program on Emerging Technologies (PoET).
Zheng-Jun Guan received her PhD on cell biology from the College of Life Sciences, Northwest University, China. She was a teacher of cell biology for eight years. She is now working as a postdoctoral scientist on the biosafety of synthetic biology and genetically modified organisms at the Institute of Botany, Chinese Academy of Sciences.
Allen Lin received a BS in Chemical–Biological Engineering and a BS/MEng in Electrical Engineering and Computer Science in 2011 from MIT, and he is currently a research technical assistant in synthetic biology at the Weiss Laboratory at MIT. Since 2009, he has worked with Prof. Kenneth Oye on synthetic biology risk assessment and management.
Ismail Mahmutoglu is a Chemist at Bauer Umwelt GmbH, a specialist on the remediation of brownfields and the treatment of waters and gases. He is a specialist for the design and manufacture of water treatment plants for decontamination, for waste water and for potable water. The range of projects he is dealing with includes complex technical treatment steps with biological treatment steps, but also in situ technologies to improve the underground conditions for the microorganism.
Kenneth A. Oye is Director of the MIT Program on Emerging Technologies with a joint appointment in Political Science and Engineering Systems. He is an NSF SynBERC PI and an iGEM judge and biosafety coordinator. He serves on the NRC Board on Global Science and Technology and the Advisory Committee for the International Risk Governance Council. Recent publications include “Adaptive licensing,” (Nature CPT, forthcoming), “Synthetic biology and the future of biosecurity” (Politics and Life Sciences, 2010), “Planned adaptation in risk regulation” (Technology Forecasting and Social Change, 2010), “Intellectual commons and property in synthetic biology” (Synthetic Biology, 2009) and “Embracing uncertainty” (Issues in Science and Technology, 2009).
Martin Österreicher has a graduate degree in law from the University of Vienna. He is currently working as a research associate at the MIT Program on Emerging Technologies (PoET). In the course of his studies in Vienna and St. Gallen, Switzerland, he focused his research on international law and genetic law.
Lei Pei completed her PhD at the Division of Clinical Bacteriology, Karolinska Institute, Sweden, in 2002. After her PhD she worked at the Division of Infectious Diseases, Department of Medicine, at the Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, as a Postdoctoral Research Fellow. Between 2005 and 2009 she completed her second postdoc position at the Flanders Institute for Biotechnology, Department of Molecular Biology, Gent University, Belgium. Since 2009 she has been working with Markus Schmidt as a postdoc on synthetic biology and risk assessment.
Manuel Porcar is an applied microbiologist and biotechnologist. He leads the Biotechnology and Synthetic Biology Laboratory at the Cavanilles Institute of the University of Valencia, where he coordinates several research efforts focusing on strain and gene selection strategies for bioremediation, biofuels production and bioenergetics. As an expert on GMOs evaluation, he is a member of the Comisión Nacional de Bioseguridad, the Spanish reference organ on GMOs. He has been actively involved in the international Genetically Engineered Machine (iGEM) competition and in the development of devices for synthetic biology. He is a convinced supporter of Darwinian approaches as a tool for synthetic biology.
Pernilla Regardh holds an MSc in Technology and Policy from the Massachusetts Institute of Technology, a BSc in Biotechnology from the Royal Institute of Technology in Stockholm, Sweden, and a BA in Political Science from Stockholm University. Her research interests include risk assessment, regulatory development and public debate over emerging biotechnologies, and as a graduate student at MIT she analyzed and compared the regulatory landscape of synthetic biology in Europe and the United States together with Dr. Kenneth Oye. Regardh recently graduated from MIT and is currently working as a strategy consultant in Stockholm.
Vincent Schachter is Vice-President for Research and Development at Total Gas and Power. Before that he was the director of Systems Biology of the French CEA, where he lead the Computational Systems Biology research group. He holds a PhD in Computer Science from the Ecole Normale Supérieure in Paris and entered bioinformatics through the field of protein interaction network analysis. He has also acquired applied experience with high-throughput experimental data – protein–protein interactions, sequence, cellular phenotypes – first as Director of Bioinformatics Research at Hybrigenics SA, a biotech company, and then as Director of Bioinformatics at CEA. He is a cofounder of the BioPathways Consortium and a participant in the BioPAX standardization effort and is a referee for several bioinformatics and biology journals.
Markus Schmidt has an interdisciplinary background with an education in electronic and biomedical engineering (Ing), biology (MSc) and environmental risk research (PhD). His research interests include the risk assessment, science–society interface and technology assessment (TA) of novel bio-, nano- and converging technologies. Since 2005 he pioneered synthetic biology safety and ethics research in Europe. He is co-founder and board member of the Organization for International Dialog and Conflict Management (IDC) and is co-founder and CEO of Biofaction. For details, see www.markusschmidt.eu.
Helge Torgersen was a researcher and lecturer at the Institute of Molecular Biology and the Institute of Biochemistry, University of Vienna from 1981 to 1989. In 1990 he joined the Institute of Technology Assessment (ITA) of the Austrian Academy of Sciences as a researcher. His main interests are comparative biotechnology policy and safety regulation, the risk assessment and public perception of transgenic organisms, science studies in biotechnology and methods of participatory technology assessment. Current interests include societal aspects of nanotechnology, genomics and synthetic biology.
Ralph D. Turlington is a graduate student in the Technology and Policy Program at MIT working with Dr. Kenneth Oye on the security implications of synthetic biology. He became interested in security during his first two years of college, spent at the United States Military Academy at West Point. Ralph graduated with a BSc in Environmental Science with a second major in Economics from the University of Virginia. His undergraduate research was on atmospheric science and pollution transport studies in the Nepal Himalayas.
Wei Wei received his PhD on Botany from the Institute of Botany, Chinese Academy of Sciences. His major research interests are in plant ecology and biodiversity conservation. He has worked on the biosafety issues of genetically modified organisms for a decade. He is now interested in studying the biosafety link between genetic engineering and synthetic biology (SB) and aims to develop proper risk assessment and management strategies of SB. He is member of the Ad Hoc Expert Group on Risk Assessment and Risk Management within the framework of the Cartagena Biosafety Protocol.
Preface
During the first decade of the 21st century the establishment of Synthetic Biology (SB), a science and engineering field that wants to turn biology into a true technology, could be observed. SB goes beyond previous efforts that use more conventional or, as some consider them, “artisan” forms of biotechnology. With the aim of making biology accessible to the needs of everyday life, SB applies engineering principles such as standardization, modularization, using hierarchies of abstraction or the decoupling of design and fabrication to biological systems in order to establish a whole new set of applications for society.
The aim of this book is to give a critical 360-degree assessment of a selected number of highly promising industrial and environmental applications enabled by SB. The assessment not only analyses to what extent SB could improve current technologies, it also approaches the potential applications from the economic, environmental, social and ethical perspective. The book summarizes these different viewpoints in order to present a balanced evaluation of the technical, economic, environmental and societal ramifications of SB applications.
Chapter 1 provides a detailed analysis of several different types of biofuel and their production, such as ethanol, non-ethanol-based fuels, fuels made from algae, biohydrogen, microbial fuel cells and bio-photovoltaic systems. It describes the technical limitations of ethanol usage and the conditions under which its production would be environmentally sustainable. It also discusses the benefits and production challenges of butanol, further the specific economic context necessary for algae production systems in order to be competitive, and the uncertainty of the environmental impact of open pond production systems. It also takes a closer look at the environmental benefits and infrastructure problems of the biohydrogen economy and finally describes the niche markets for environmentally friendly microbial fuel cells.
Chapter 2 details a number of applications for bioremediation. It focuses on possible methods of how to detect environmental pollutants, views the environmental and social benefits of water treatment, soil and groundwater decontamination, and describes the market opportunities in solid waste treatment. Furthermore, Chapter 2 reports on the challenges of one of the most important applications of SB in the light of future global water scarcity, namely, water desalination by using special biomembranes. Another global environmental challenge that might be turned into a business opportunity is SB-enabled CO2 recapture.
Chapter 3 is devoted to the assessment of SB-produced biomaterials, such as biopolymers (bioplastics), bulk chemicals or fine chemicals. This chapter highlights the environmental benefits of SB that are reached by leaving behind synthetic chemistry which often comprises an energy-intense production system including toxic side products that could altogether be avoided by using cell factories designed by SB. Another focus in this chapter is devoted to cellulosomes that can be used to degrade cellulose and hemicellulose, and the tremendous impact its use may have on the economy and the environment.
Chapter 4 explores two promising SB technologies that are still at an experimental stage. Both protocells and xenobiological systems could one day provide a whole new set of applications, ranging from smart semi-living systems in the environment to the installation of a genetic firewall in order to impede horizontal gene-flow between natural and engineered organisms, touching on a number of environmental and ethical questions.
The final chapter, Chapter 5, takes the reader on a guided tour through the regulatory frameworks applied to SB. Acknowledging regional differences, this chapter provides insight into the situation in the USA, Europe and China. In addition to laying out the existing regulatory framework, Chapter 5 also suggests improvements and adaptations in order to deal with upcoming technical inventions.
My special thanks go to all the contributors to this book, who provided their expertise coming from academia, industry and non-profit organisations. I would like to thank Wiley for kindly accepting the publication of this book. Last but not least, I would also like to thank you, the reader, for your interest in the scientific, economic, environmental, social and ethical consequences of upcoming SB applications.
I hope that this book contributes to a broader understanding of the many societal ramifications of SB and helps in making smarter decisions about upcoming SB tools and applications.
Markus Schmidt
Acknowledgments
Markus Schmidt, Ismail Mahmutoglu, Manuel Porcar, Rachel Armstrong, Mark Bedau and Lei Pei gratefully acknowledge the financial support provided by the European Commission’s seventh framework programme: “TARPOL Targeting environmental pollution with engineered microbial systems à la carte”, 2008–2010, FP7 EU-KBBE-212894. Antoine Danchin gratefully acknowledges the support provided by the Fondation Fourmentin-Guilbert and the EU’s 7th framework programme “Microme” grant KBBE_2007_3-2_08_222886_2. Markus Schmidt, Lei Pei, Wei Wei and Zheng-jun Guan gratefully acknowledge the financial support provided by the FWF (Austrian Science Fund) and the NSFC (National Natural Science foundation of China) joint-project “Investigating the biosafety and risk assessment needs of synthetic biology in Austria (Europe) and China,” project number I215-B17 and NSFC 30811130544. Markus Schmidt gratefully acknowledges the financial support provided by the FWF (Austrian Science Fund) project “SYNMOD: Synthetic biology to obtain novel antibiotics and optimized production systems,” project number I490-B12, through the EUROSYNBIO Programme of the European Science Foundation. The NSF Synthetic Biology Engineering Research Center (SynBERC) provided financial support for Shlomiya Bar-Yam, Jennifer Byers-Corbin, Rocco Casagrande, Florentine Eichler, Allen Lin, Martin Österreicher, Pernilla C. Regardh, Ralph D. Turlington, Kenneth A. Oye under NSF Grant 050869. Thanks to Michael Stachowitsch for English proofreading of the Introduction and Chapters 1 to 4.
Executive Summary
Markus Schmidt
This book provides a glimpse into the future of synthetic biology (SB) and its potential applications in the area of environmental and industrial biotechnology. There are a number of applications where SB could well make a difference in making society more economically and environmentally sustainable. This report highlights four major areas (biofuels, bioremediation, biomaterials, novel developments in SB) with a total of 20 applications where SB has a great potential to improve currently available technologies. Each of the 20 applications has been assessed in detail in order to determine: (i) to what extent SB could improve current technologies, (ii) what the economic impact of SB could be, (iii) what the environmental benefits and downsides could be and (iv) whether any social or ethical problems would be created, exacerberated or improved. This assessment is intended to support not only researchers and students, but also national and international funding agencies in their decisions to allocate resources to SB-based biotech applications while taking into account any foreseeable economic, environmental and social/ethical issues. Our outlook is based on state of the art science, although there is clearly a considerable degree of uncertainty about future development paths. This uncertainty needs to be acknowledged when providing recommendations for what we see as the most promising directions for SB in environmental biotechnology. Another area where uncertainties might be ahead, is the regulatory framework such as laws, regulations, guidelines and code of conducts, for synthetic biology. As of 2011, hardly any specific regulation has been produced for SB, for the moment current regulations – originally put in place to deal with genetic engineering – cover SB more or less sufficiently well. This situation, however, will change sooner or later, requiring future adaptations to the regulatory status quo.
Biofuels
We are convinced that synthetic biology can help to produce state of the art and next generation biofuels. Current efforts are mainly targeted towards an improved production of bio-ethanol from agricultural products, although this approach harbors significant problems because ethanol exhibits certain technical drawbacks (miscible with water, limited use in existing engines). Other non-ethanol biofuels such as bio-butanol or biodiesel are much better suited to replace petroleum-based gasoline, as their chemical properties resemble it much closer. Synthetic biology could help to overcome current impasses in the production of butanol and other non-ethanol fuels, namely poor fermentation yield and toxicitiy to butanol-producing microorganisms. One shortcoming faced by most biofuels produced from plant material is limitations in the use of hemi- and lignocellulosic material. Any improvement in that area would increase the economic feasibility of biofuel production. One important problem will arise should synthetic biology be able to help solve the above technical issues, namely that more and more agricultural land will be devoted to plant energy crops instead of food crops. In order to avoid such competition with food, we suggest also using non-food-competing biological resources such as perennial plants grown on degraded lands abandoned for agricultural use, crop residues, sustainably harvested wood and forest residues, double crops and mixed cropping systems, as well as municipal and industrial wastes.
In addition to agricultural-based ethanol, biodiesel and butanol, algae-based biofuels and biohydrogen also deserve consideration. Current concepts foresee a significant advantage of algae-based over agriculture-based biofuels because of higher yield per area and an independence from arable land and clean water. Initial calculations, however, predict that future algae production systems will be economically feasible only if the price for one barrel oil is consistently above US$ 100 and if the production systems entail an area of at least 200 ha. The capital costs of such large production facilities will probably lead to an exlusion of small and medium enterprises (SMEs) and favor “big oil” (or “big energy”) companies. Still, algae production systems could be a highly promising avenue of future fuel production once major obstacles such as algae genomics, metabolism and harvesting are overcome. Although bio-hydrogen has been praised as an extremely promising fuel by many scientists, our assessment is more cautious. Hydrogen is only useful as fuel if large changes in infrastructure take place (distribution and storage systems, new fuel cell engines). This points to a more distant future beyond 2050, also termed as the hydrogen economy. Although synthetic biology could well help improve the yield of hydrogen-producing cyanobacteria, the actual impact of hydrogen in society and economy depends much more on other areas such as infrastructure. Finally, we analyzed the prospects of microbial fuel cells (MFC) as an energy converter. Although we see MFCs as extremely promising and an area where synthetic biology could contribute significantly, it will most likely be applied only in certain niche markets and selected areas of application, rather than large-scale deployment due to the limited energy production.
Bioremediation
Bioremediation is an area with a great potential of benefits provided by synthetic biology. Bioremediation is usually applied on materials with a massive occurence such as solid (organic) wastes, sewage, industrial waste water, contaminated soil or contaminated groundwater – all measured in millions of tons or cubic meters. We believe that SB has the potential to create tools to improve the treatment methods, saving costs and environmental resources. Moreover, it can provide methods to produce energy or valuable goods from waste or wastewater. It can also provide tools for producing fresh or drinking water from either contaminated water or seawater. Another possible field of application is the production of biosensors to monitor environmental goods and hazards. In a differentiated evaluation, we conclude that biosensors provided by SB tools would have a great positive effect on the environment because they can help to survey environmental hazards more precisely and effectively. Their economic and social impact, however, is rather low due to their niche-product status.
Synthetic biology-based approaches may provide a way of capturing, storing and recycling carbon dioxide. This may be through the re-engineering of existing organisms or the creation of novel carbon processes, especially using bottom up approaches where inorganic chemistry is linked to living processes through agents, such as the emerging protocell technology.
Synthetic biology-based carbon capture may not be able to sink sufficient carbon dioxide to completely remediate the currently escalating levels being released through fossil fuel consumption. This is because very large scale geoengineering-scale approaches would be necessary. This approach, however, does offer the possibility of carbon capture and recycling, which current industrial-scale processes cannot do.
Our recommendation is that, because of the scale of the problem with carbon dioxide emissions and the urgent need for remediation, synthetic biology approaches be supported in order to develop the next generations of carbon capture technologies. These will do more than merely store the carbon dioxide but will recycle it into fuels and biopolymers with positive environmental impact.
Another positive impact, particularly to the environment, can be expected for soil and groundwater remediation, especially with regard to enhancing the clean-up efficieny and the development of new methods. In this field, the economic and social impacts are rather moderate because it is a specific field with a limited scope of time.
We expect the strongest impact in solid waste and wastewater treatment and for water desalination. The importance of the latter cannot be overstated in a world where billions of people have no access to clean drinking water or to freshwater for agricultural use. Solid waste and wastewater treatment also bear a great potential for improvement by synthetic biology due to their sheer amount and their considerable organic content. We therefore strongly recommend supporting the development of these applications. One possible constraint deserves to be mentioned: solid waste and waste water cannot be treated in sealed vessels or rooms, simply due to their huge volumes. They have to be treated openly in piles or basins. Therefore, the use of engineered cells may create interactions with the environment, a problem that must be kept in mind. At the same time, we expect no limitations in the use of non-proliferative systems such as enzymes or protocells created with the aid of synthetic biology.
Biomaterials
Synthetic biology will have a significant impact on the biomaterials market, particularly in the areas of fine chemicals and bioplastics. We recommend a tool box of products that will act as biodegradable materials. The bulk chemicals industry will also be significantly affected by synthetic biology-based technology. The acceptance of this approach and therefore its environmental impacts will be slower, although when new practices are adopted, changes will last longer and take place on a much larger scale. In the fine chemicals industry, the incentives for investment relate to the economic potential of the end product (in contrast to bulk chemical manufacturing). The payoffs could have environmental benefits, although these may be largely limited to more efficient use of energy because the core manufacturing practice relies on petrochemicals. There is also limited potential for synthetic biology-based techniques to help avoid recalcitrant molecules in the production process. Accordingly, investment in synthetic biology-based processes in bulk chemicals is likely to have a positive overall effect on the manufacturing systems used in running the plants. These include the use of biodiesel and less overall chemical waste. Moreover, the large scale at which these processes take place mean that small changes may have significant positive environmental effects. For both fine and bulk chemical production we recommend deploying the “chemical building block system” as designed by (or similar to) the US Department of Energy (DoE).
The field of biopolymers and bioplastics urgently needs revisiting in terms of its current labeling for recycling purposes. This is because categorization of the various products is extremely complex, with negative economic consequences (bioplastics are not necessarily biodegradable). We recommend applying a method that renders recognizable those bioplastics that need recycling and those that can be composted, before introducing large-scale use of synthetic biology for bioplastics production. There is an urgent need to develop completely biodegradable plastics; this would benefit from focused synthetic biology research and development in this field. Additionally there is a pressing need for high-performance structural bioplastics for manufacturing coupled with completely biodegradable additives. Both of these significant growth areas in the bioplastics industry could be greatly improved by synthetic biology-based research.
Investment is particularly needed in research and development for new methods and products that will expand and develop tools and manufacturing processes with reduced environmental impact compared with the current manufacturing approaches. Here, adequate biosafety constraints on large-scale manufacturing units need to be established. Cellulosomes (complex molecules that degrade hemi- and lignocellulosic material) possess high economic potential for biofuels, paper and waste processing. Synthetic biology has the potential to design more efficient and completely new cellulosome complexes, yielding new, efficient cellulose-digesting proteins. We recommend open sourcing of the cellulosome technology due to the justice of distribution issues involved in the technology.
Novel Developments in Synthetic Biology
Protocell technology represents a bottom up approach to synthetic biology that bridges inorganic and organic processes. Protocell technology promotes a better understanding of synthetic biology as a whole to develop new technologies. Although the research is in an early stage, the development of potentially radically novel and significant environmental interventions is feasible. Examples include remediation of carbon emissions and alternative biofuels technology. One strong recommendation is the investment in basic science to underpin and support the research while private investment is being geared up.
Protocell technology has a huge potential to offer tools and methods radically different from those previously encountered with synthetic biology approaches. This reflects its bottom up nature and its overlap with basic chemistry. This also calls for looking into a toolbox of potential products and for investigating issues related to make the technology open source. Xenobiology (also known as chemical synthetic biology) is another bottom up approach to design and construct radically new biological systems with properties not found in nature. Using non-canonical amino acids, alternative base pairs to enlarge the genetic alphabet, or different chemcial backbones in a xenonucleic acid, these chemically modified organsims and systems will enable a much higher level of biosafety when using engineered biosystems for, or in, the environment. For example, novel enzymes (such as amylase) with non-canonical amino acids can be used to reduce the optimal temperature for breaking starch down into glucose. This would save enormous amounts of energy and help reduce greenhouse gas emissions. This would help reduce greenhouse gas emissions. Organisms with an enlarged genetic alphabet or a DNA with a different chemical backbone could be designed by synthetic biology. This approach would impede horizontal gene transfer and genetic pollution between engineered and natural organisms. Similar to protocells, xenobiology is in a very early stage of development and requires increased support for basic research in order to introduce radically new concepts and applications.
Table A summarises our assessment of each of the 20 applications. For further details see the following chapters.
Table A Assessment of potential synthetic biology applications in environmental biotechnology over the next 10–15 years.
Introduction
Markus Schmidt
The following report provides a glimpse into the future of synthetic biology (SB or synbio) and its potential applications in the area of environmental biotechnology. There are a number of applications where SB could well make a difference in order to make society more economically and environmentally sustainable. In this report we highlight four major areas (biofuels, bioremediation, biomaterials and novel developments in SB) with a total of 20 applications (3 general areas and 17 specific applications) where SB can probably improve currently available technologies. Each of the 20 applications has been assessed in detail in order to determine to what extent SB could improve current technologies. We asked:
What could be the economic impact of SB?
What could be the environmental benefits and downsides?
Would any social or ethical problems be created, exacerberated or improved?
This assessment is intended not only to guide scientists and students when selecting their next research topic, but also to support national and international funding agencies in their decisions to allocate resources to SB-based biotech applications while taking into account any foreseeable economic, environmental and social/ethical issues.
What Are Synthetic Biology Applications?
Although the term “synthetic biology” was already in use about 100 years ago – in 1910 and 1912 by Stephane Leduc (Campos, 2009) – the contemporary version is a relatively young field at the intersection of biology, engineering, chemistry and information technology. Not atypical for an emerging science and engineering field, a variety of definitions are circulating in the scientific community, and no one definition would receive total support by the researchers involved in SB activities. The probably least contested definition is that found on the SB community webpage (http://syntheticbiology.org/):
“Synthetic Biology is:
Synthetic biologists are currently working to:
specify and populate a set of standard parts that have well-defined performance characteristics and can be used (and re-used) to build biological systems,
develop and incorporate design methods and tools into an integrated engineering environment,
reverse engineer and re-design pre-existing biological parts and devices in order to expand the set of functions that we can access and program,
reverse engineer and re-design a “simple” natural bacterium,
minimize the genome of natural bacteria and build so-called protocells in the lab, to define the minimal requirements of living entities, and
construct orthogonal biological systems, such as a genetic code with an enlarged alphabet of base pairs.”
Activities that fall under SB are currently performed in several (sub)fields. For various reasons, these activities are not always addressed under the term proper, while others use the label for still different endeavors. By and large, however, the following activities are usually subsumed under SB (Bedau et al., 2009; Benner and Sismour, 2005; Deplazes, 2009; Luisi, 2007; O’Malley et al., 2008; Schmidt et al., 2009):
DNA synthesis (or synthetic genomics);
Engineering DNA-based biological circuits (based on metabolic engineering but using real engineering principles);
Defining the minimal genome (or minimal cell);
Building protocells (or synthetic cells);
Xenobiology (aka chemical synthetic biology).
Which Synthetic Biology Applications Did We Consider?
The aim of this study was to tackle environmental pollution using synthetic biology. Examining the different fields of biotechnology reveals several color-coded subcategories, defined by their major area of application: red biotechnology, that is applied to medical processes; green biotechnology, that is biotechnology applied to agricultural processes; white biotechnology, also known as industrial biotechnology, is biotechnology applied to industrial processes; brown (gray) biotechnology is also known as environmental biotechnology and involves different forms of biodegradation and sustainable production; and blue biotechnology, that is the marine and aquatic applications of biotechnology.
In addition to these frequently used terms, we can also find yellow biotechnology, which is sometimes used as a synonym for the venous (recycling) biotech industry, and black biotechnology, which describes the use of biotech for bioweapons or bioterrorism.
For our work, two biotechnology areas were of greater interest: environmental biotechnology (including bioremediation, green manufacturing processes, sustainable development) and industrial biotechnology, which aims to prevent pollution, conserve resources and reduce costs. Bioremediation is uniquely assigned to environmental biotechnology, but what is described as sustainable development or green (environmentally friendly) manufacturing processes can be found in both categories.
Selecting and Assessing Synthetic Biology Applications
The categories of environmental and industrial biotechnology encompass a variety of applications throughout different industrial sectors, as shown in Table 1.
Table 1 Examples of environmental biotech industry applications.a)
Fine chemical production (e.g., pharmaceutical products, cosmetics) and biohydrogen production
Bulk chemical production
Chem/bio-warfare agent decontamination
Bio-ethanol transportation fuels
Pulp and paper bleaching
Chiral compound synthesis
Specialty textile treatment
Pharmaceutical manufacturing/processing
Antibiotic production
Synthesis of vanillin and other food flavoring agents
Electroplating/metal cleaning
Biopolymers/plastics
Nutritional oil production
Rayon production
Sweetener production
Metal refining
Oil well drill hole completion
Oil and gas well completion
Textile dewatering
Vitamin production
Vegetable oil degumming
Coal, oil and gas desulfurization
Biological fuel cells
Leather degreasing
Soil decontamination (recalcitrant compounds)
Control of biofilms
Solid waste treatment (industry, mechanical-biological treatment)
Bio-solar panels
Water treatment (groundwater, industrial, domestic, land fill leachate)
More efficient biogas production facilities
Air treatment (biofilter)
a) See: http://www.bio.org/ind/pubs/cleaner2004/ and http://www.bio.org/ind/background/thirdwave.asp.
After identifying a range of applications like the ones shown in Table 1, we selected 20 (potential) SB applications that we estimate: (a) have a considerable impact on the economy, environment and/or society and (b) could be available on the market within the next 15 years or lay the foundation for promising new applications. We then selected the 20 applications for further analysis (see Table 2). We then asked the following questions for each of the 20 selected applications:
How could SB improve or enable the application?
What is the foreseeable economic impact in case SB improves improves/enables the application?
What will be the most likely environmental impact?
What are potential social and ethical aspects that we need to consider?
Table 2 List of selected SB applications.
1 Biofuels1.1 Biofuels in general1.2 Ethanol1.3 Non-ethanol fuels1.4 Algae-based fuels1.5 Hydrogen production1.6 Microbial fuel cell (mfc) and bio-photovoltaic2 Bioremediation2.1 Bioremediation in general2.2 Detection of environmental pollutants (biosensors)2.3 Water treatment2.4 Water desalination with bio-membranes2.5 Soil and groundwater decontamination2.6 Solid waste treatment2.7 Carbon dioxide recapturing
3 Biomaterials3.1 Biomaterials in general3.2 Biopolymers/plastics3.3 Bulk chemical production3.4 Fine chemical production3.5 Cellulosomes4 New developments in synthetic biology4.1 Protocells4.2 Xenobiology
In the last step, we prepared recommendations based on our 360-degree analysis (based mainly on literature analysis) of the economic, environmental, societal and ethical impact of selected synbio applications. The report benefits from the fact that the authors come from different backgrounds including non-governmental organizations, universities, small and medium enterprises, and large enterprises. The structure of the report and its recommendations reflect our understanding of the management of new and emerging science and technologies: we sign up neither to an “anything goes” nor a “stop everything” regime, but try to assess different technologies and applications case by case in a more balanced mode of operation (see Figure 1).
Figure 1 A model of the relationships between the concepts of risk, science and precaution when new technologies are assessed. The elipse represents the intended approach chosen by the authors of this report.
(Source: Sterling, 1999).
Although our assessment is based on the scientific state of the art, there is of course a notable degree of uncertainty about future development paths. We have to acknowledge the uncertainties when giving recommendations for what we see as the most promising directions for SB in environmental biotechnology.
The Regulatory Context for Synthetic Biology
In the final three chapters of this book, we take a look at the state of the art regulatory environment in which SB develops. The analysis of the legal situation in the United States, Europe and China shows that almost the entire field of SB is dealt with by a set of regulations, laws, and guidelines originally designed to deal with “traditional” genetic engineering. Only a few guidelines or self-imposed code of conducts have been prepared specificially for SB, especially regarding biosecurity risks related to DNA synthesis. Although the current set of regulations appear to cover most of what SB is doing (in 2011), it is foreseeable that, in the not so distant future, a number of adaptations need to be made to deal with novel developments.
References
Bedau, M.A., Parke, E.C., Tangen, U., and Hantsche-Tangen, B. (2009) Social and ethical checkpoints for bottom-up synthetic biology, or protocells. Syst. Synth. Biol., 3, 65–75.
Benner, S.A., and Sismour, A.M. (2005) Synthetic biology. Nat. Rev. Genet., 6, 533–543.
Campos, L. (2009) That was the synthetic biology that was, in Synthetic Biology: The Technoscience and Its Societal Consequences (eds M. Schmidt, A. Kelle, A. Ganguli-Mitra, and H. deVriend), Springer, Chapter 2, pp. 40–48.
Deplazes, A. (2009) Piecing together a puzzle. An exposition of synthetic biology. EMBO Rep., 10, 428–432.
Luisi, P.L. (2007) Chemical aspects of synthetic biology. Chem. Biodivers., 4, 603–621.
O’Malley, M.A., Powell, A., Davies, J.F., and Calvert, J. (2008) Knowledge-making distinctions in synthetic biology. Bioessays, 30, 57–65.
Schmidt, M., Ganguli-Mitra, A., Torgersen, H., Kelle, A., Deplazes, A., and Biller-Andorno, N. (2009) A priority paper for the societal and ethical aspects of synthetic biology. Syst. Synth. Biol., 3, 3–7.
Sterling, A. (1999) On Science and Precaution In the Management of Technological Risk. An ESTO Project Report Prepared for the European Commission – JRC Institute Prospective Technological Studies. http://ftp.jrc.es/EURdoc/EURdoc/EURdoc/eur19056en.pdf (accessed 7 September 2010).
1
Biofuels
Markus Schmidt, Manuel Porcar, Vincent Schachter, Antoine Danchin, and Ismail Mahmutoglu
1.1 Biofuels in General
1.1.1 Introduction
In 1973, over 86% of the world’s total primary energy supply came from fossil fuels. While the energy supply has increased since then (from about 6 Gtoe1) in the 1970s to 12 Gtoe in 2007), the share of fossil fuels remains high. In 2007, still over 81% came from fossil fuels (gas: 20.9%; oil: 34%; coal: 26.5%; IEA, 2009). The European Community (EC) is strongly dependent on fossil fuels for its transport needs and is a net importer of crude oil (EC, 2010). Numerous experts predict that oil production will reach a ceiling by 2020, while the demand will continue to grow, pulled by China and India. Facing this demand calls for finding alternatives in petroleum products. At the same time, concerns are increasing about climate change and the potential economic and political impact of limited oil and gas resources. To address these issues and reduce our dependency on fossil fuels the EC has adopted measures2) to encourage the production and use of sustainable biofuels (e.g., achieve 5.75% of biofuels among total fuel in the EC). Interestingly, the agricultural policy in Europe or in the United States is also probably the most important driver for the biofuel production. From 2000 to 2008, biofuel production in the United States has increased 82% even though that market accounts for less than 5% of total fuel consumption. Nevertheless, current biofuel production is based only on the exploitation of the storage organs of agricultural plants (sugars or oils). Research and development efforts are necessary to diversify the feedstock available, to limit the impact on food markets, and to produce more efficient molecules as biofuels. This new SB application is probably one of the success keys, as suggested by new petroleum investments (Exxon’s investment in Craig Venter’s synthetic genomics start up, BP invested in Qteros, French Total invested in Gevo, Amyris and Coskata).
Biofuels from biomass (e.g., plant stalks, trunks, stems, leaves) are designed to significantly reduce dependence on imported oil and decrease the environmental impacts of energy use. Biotech research is critical for accelerating the deconstruction of (cellulosic) biomass into sugars that can be converted to biofuels. Woodchips, grasses, cornstalks, and other ligno-cellulosic biomass are abundant but more difficult to break down into sugars than cereals (corn, wheat, etc.), a principal source of fuel ethanol production today. Cellulosic ethanol is therefore one of the proposed cornerstones for our energy needs. There are, however, other alternatives both in terms of feedstock and end product (e.g., butanol). Butanol is assumed to hold great promise. Aquatic biomass, such as algae, does not compete with arable land for food production. Algae can be used for the production of a variety of products, including biodiesel and hydrogen. In a long-term perspective, producing hydrogen or even electricity directly from solar energy and water by means of artificial photosynthesis would provide an almost unlimited source of energy (Thomassen et al., 2008).
Biotechnology and especially synthetic biology can play a key role in increasing production and promoting the use of sustainable bioenergy through:
Development of next-generation biofuel feedstocks,
Advanced sunlight to biomass to bioenergy conversion,
By considering socio-economic and environmental challenges when designing technological solutions.
Table 1.1 provides an overview of different biofuels and the technology and feedstock needed to produce them.
Table 1.1 Overview of different generations of biofuels (UNEP, 2009).
Traditional biofuels
Basic technology
Feedstocks
Solid biofuels
a)
Traditional use of dried biomass for energy
Fuel wood, dried manure
First-generation biofuels (conventional biofuels)
Plant oils
b)
As transport fuel: either adaptation of motors for the use of plant oils; or modification of plant oils to be used in conventional motors
Rapeseed oil, sunflower, other oil plants, waste vegetable oil
For the generation of electricity and heat in decentralized power or CHP stations
Rapeseed oil, palm oil, jatropha, other oil plants
Biodiesel
Transesterification of oil and fats to provide fatty acid methyl ester (FAME) and use as transport fuel
Europe: rapeseed, sunflower, soya
United States: soya, sunflower
Canada: soya, rapeseed (canola)
South and Central America: soya, palm, jatropha, castor
Africa: palm, soya, sunflower, jatropha
Asia: palm, soya, rapeseed, sunflower, jatropha
Bioethanol
Fermentation (sugar); hydrolysis and fermentation (starch); use as transport fuel
United States: corn
Brazil: sugar cane
Other South and Central American countries: sugar cane, cassava
Europe: cereals, sugar beets
Canada: maize, cereals
Asia: sugar cane, cassava
Africa: sugar cane, maize
Biogas (CH
4
, CO
2
, H
2
)
Fermentation of biomass used either in decentralized systems or via supply into the gas pipeline system (as purified biomethane):
Energy crops (e.g., maize, miscanthus, short rotation wood, multiple cropping systems); biodegradable waste materials, including animal sewage
(1) To generate electricity and heat in power or CHP stations
(2) As transport fuel, either 100% biogas fuel or blending with natural gas used as fuel
Solid biofuels
Densification of biomass by torrefaction or carbonization (charcoal)
Wood, grass cuttings, switchgrass; grains; charcoal, domestic refuse, dried manure
Residuals and waste for generation of electricity and heat (e.g., industrial wastes in CHP)
Second-generation biofuels (advanced biofuels)
Bioethanol
Breakdown of cellulosic biomass in several steps including hydrolysis and finally fermentation to bioethanol
Ligno-cellulosic biomass like stalks of wheat, corn stover and wood; “special energy or biomass” crops (e.g.,
Miscanthus
); sugar cane bagasse
Biodiesel and “designer”-biofuels such as bio-hydrogen, bio-methanol, DMF
c)
, bio-DME
d)
, mixed alcohols
Gasification of low-moisture biomass (<20% water content) provides “syngas” (with CO, H
2
, CH
4
, hydrocarbons) from which liquid fuels and base chemicals are derived
Ligno-cellulosic biomass like wood, straw, secondary raw materials like waste plastics
Third-generation biofuels (advanced biofuels)
Biodiesel, aviation fuels, bioethanol, biobutanol
Bioreactors for ethanol (production can be linked to sequestering carbon dioxide from power plants); transesterification and pyrolysis for biodiesel; other pyrolysis for biodiesel; other future technologies
Marine macro-algae or micro-algae in ponds or bioreactors
a) Traditional use of biomass included for complete overview.
b) Also known as straight vegetable oil. Plant oil used as direct fuel in transport is common in German agriculture with about 838 000 tonnes, mostly rapeseed oil, in 2007, representing 1.4% of total fuel consumption in transport.
c) 2,5-Dimenthylfuran.
d) Dimethyl ether.
1.1.2 Economic Potential
The European Union and the United States have already created an artificial market through energy policies that specify the required rate of incorporation of biofuels in petroleum products. They also support this path through important tax rebates. However, with the arrival of the oil production ceiling and thus the increase in oil prices, a real market will be created and these sectors are likely to be profitable. According to the IEA, 45 million barrels per day could be supplied by biofuels in 2030, making up the deficit in petrol production (see Table 1.2).
Table 1.2 Optimistic scenario of alternative fuel introduction until 2020 in the European Union (Biofuels Platform, 2010).
World ethanol production for transport fuel tripled between 2000 and 2007 from 17 billion to more than 52 billion liters, while biodiesel expanded 11-fold from less than 1 billion to almost 11 billion liters. Altogether, biofuels provided 1.8% of the world’s transport fuel. Recent estimates indicate a continued high growth. From 2007 to 2008, the share of ethanol in global gasoline-type fuel use was estimated to increase from 3.7 to 5.4%, and the share of biodiesel in global diesel-type fuel use from 0.9 to 1.5%. Currently, the main suppliers for transport biofuels are the United States, Brazil and the European Union. Production in the United States consists mostly of ethanol from corn starch, in Brazil of ethanol from sugar cane, and in the European Union mostly of biodiesel from rapeseed. Investment into biofuel production capacity probably exceeded $ 4 billion worldwide in 2007 and is growing rapidly. Industry, with government support, is also investing heavily in the development of biofuels. The current biofuel production has been stimulated by biofuel subsides, fuel blending mandates, national interest in energy security, climate change mitigation and rural development programs (see Table 1.3).
Table 1.3 Estimates on future economic indicators in the United States, based on the Renewable Fuel Standard as specified in the US Energy Independence and Security Act of 2007 (BIO-ERA, 2009; EPA, 2010).
International trade in ethanol and biodiesel has been small so far (about three billion liters per year in 2006/07), but is expected to grow rapidly in countries like Brazil, which reached a record-high of about five billion liters of ethanol fuel export in 2008 (Figure 1.1). Predictions forecast that global use of bioethanol and biodiesel will nearly double from 2007 to 2017. Most of this increase will probably be due to biofuel use in the United States, the European Union, Brazil and China. But other countries could also develop towards significant biofuel consumption, among them Indonesia, Australia, Canada, Thailand and the Philippines.
Figure 1.1 Proportion of global production of liquid biofuels in 2007
(Source: UNEP, 2009).
Regarding the global long-term bioenergy potential, estimates depend critically on the underlying assumptions, particularly on the availability of agricultural land for non-food production. Whereas more optimistic assumptions yield a theoretical potential of 200–400 × 1018 J/year or even higher, the most pessimistic scenario estimates 40 × 1018 J/year. More realistic assessments considering environmental constraints estimate a sustainable potential of 40–85 × 1018 J/year by 2050. For comparison, current fossil energy use totals 388 × 1018 J. These estimations do not take into account biofuel production from non-agricultural biomass (e.g., bio-photovoltaics).
In 2009, total oil and fuel demand worldwide was 84.9 million barrels/day (mb/d), of which 2 mb/day were biofuels (about 2.3%). Not including the United States and Brazil, the global biofuel supply is only about 0.5 mb/day. Examining the global supply of fuel for 2010 reveals only little growth compared to the previous year (Figure 1.2). Among the key sources of global growth in 2010, however, are biofuels (+210 kb/day) (IEA, 2010).
Figure 1.2 Overview of the biofuel life cycle with inputs and relevant environmental impacts.
1.1.3 Environmental Impact
The effects of biofuels on the environment include changes in the emission of greenhouse gases (GHG), the displacement of non-renewable fuels, a positive effect on water and air quality, as well as a beneficial influence on biodiversity, eutrophication and acidification of soils. Currently, biofuel production is mainly related to ethanol and biodiesel. These require an agricultural bio-resource such as sugar cane, corn or rapeseed, as well as a considerable amount of water and fertilisers, not to mention pesticides. Today, most environmental effects are strongly linked to the agricultural practices of the bioenergy crop cultivation.
The extension of cropland for biofuel production is continuing, in particular in tropical countries where natural conditions favor high yields. In Brazil, the planted area of sugar cane comprised nine million hectares (Mha) in 2008 (up 27% since 2007). Currently, the total arable land of Brazil covers about 60 Mha. Also, the total cropping area for soybeans, which is increasingly being used for biodiesel, could potentially be increased from 23 Mha in 2005 to about 100 Mha. Such expansion is most likely on the pastureland and in the savannah (cerrado). For example, palm oil expansion in Southeast Asia is considered as the leading cause of the lost biodiversity of rainforest. Taking an example from Indonesia, plantations of 20 Mha for palm oil trees are planned, while the existing stock has already been at least 6 Mha. Two-thirds of these expanded palm oil cultivations in Indonesia will be grown on lands converted from rainforests, with one-third on previously cultivated or currently fallow land. Of the converted rainforest areas, one-quarter contained peat soil with a high carbon content – resulting in particularly high GHG emissions when drained for oil palms. Based on the 2009 estimate by Bringezu et al., by 2030, a share of 50% from peat soils is expected. If current trends continue, in 2030 the total rainforest area of Indonesia will be reduced by 29% as compared to 2005, and will only cover about 49% of its original area in 1990. Figure 1.3 shows the estimated positive and negative environmental effects of different uses of biomass, including liquid transport fuels (Bringezu et al., 2009).
Figure 1.3 Comparative relief of environmental pressure through use of biomass for heat/electricity, transport fuel and material products
(Source: UNEP, 2009).
The Scientific Committee on Problems of the Environment (SCOPE, 2009) conducted a project on the environmental impact of biofuels and recommended – in line with Tilman et al. (2009) – that: many of the adverse effects of biofuels on the environment (e.g., loss of biodiversity, eutrophication, acidification of soils, water pollution, production of GHG, in particular nitrous oxide) could be reduced by using best agricultural management practices, if production is kept below sustainable production limits.
In general, biofuels made from organic waste are environmentally more benign than those from energy crops. Using biomass primarily for material purposes, reusing and recycling it, and then recovering its energy content can yield multiple dividends (Figure 1.4).
Figure 1.4 Schematic view of the biofuel conversion process (US DOE, 2010).
Low-input cultivation of perennial plants, for example, from short-rotation forestry and grasslands, may be an effective source of cellulosic biomass and provide environmental benefits (reduced pollution and lower greenhouse gas emissions). Careful attention to maintaining the long-term productivity of these systems through nutrient additions (particularly potassium) is required.
New liquid hydrocarbon fuels (see Section 1.3) produced from cellulosic biomass are under development and seem likely to offer several advantages over producing ethanol from cellulose in terms of more efficient yields and less environmental impact (Figure 1.5). The economic viability of this technology still needs to be proven, and potential conflicts with traditional wood-based industries should be considered. Note, however, that the aromatics present in lignin provide a good substrate as a traditional fuel, while they are, with our present knowledge, difficult to convert to biofuels.
Figure 1.5 Schematic pathway from photosynthesis in plants to biomass to ethanol.
