Speakers & responsible persons

Dr. Monika Griefahn is chairwoman of the board of the eFuel Alliance and a founding member of Greenpeace Germany. From 1984 to 1990, Monika Griefahn was the first woman to serve on the International Board of Greenpeace. From 1990 to 1998, she served as Environment Minister in Lower Saxony. Then as now, she advocated for a new energy policy: for renewable energies and the phase-out of nuclear energy. From 2012 to 2018, Monika Griefahn was also Director of Environment and Society at the cruise line AIDA Cruises. She played a key role in the company's realignment toward the use of liquefied natural gas as a ship fuel. Monika Griefahn is involved in many voluntary commitments and was awarded the Order of Merit of the Federal Republic of Germany in 2018.

Thorsten Herdan is CEO of HIF EMEA and vice-chairman of the board of the eFuel Alliance. Thorsten has a broad experience in industry as well as government business. As former Director General Energy in the German Ministry of Economy and Energy and current Chairman of the supervisory board of the first German state-owned fund, he combines financial experience from an industry, government, and asset management perspective. He holds a Dipl.Ing. Degree Mechanical Engineering from the RWTH University of Aachen.

Elmar Kühn has served as Chief Executive of UNITI since 2006. UNITI is the Germany's oldest and largest trade body representing the independent fuel and energy sector. He studied law at the University of Münster and qualified after passing both state law exams at the Higher Regional Court in Hamm. Before joining UNITI, Elmar Kühn worked for the Christian Democratic Party in North Rhine-Westphalia. With deep expertise in the petroleum industry and fuel retail sector, he is widely recognised as a leading voice for the industry. He is also a committed advocate for renewable fuels and played a key role in establishing the eFuel Alliance.

Dr. Lars Menger is a member of the Board of the eFuel Alliance. Following his training as a chemical-technical assistant at the Dr. Flad Institute in Stuttgart, he studied physical chemistry at the University of Cologne. He completed his diploma with a thesis on the formulation of water-diesel microemulsions with high ethanol content and went on to earn a PhD focused on optimising water-based fuels and assessing their emissions under real-world conditions. Lars Menger held various positions at BMW AG in Munich. As a specialist, he worked on fuels, additives as well as operating fluids and emissions, before being appointed project manager for alternative fuels in 2017. In parallel, he completed a Master of Business Administration und Engineering at the Munich University of Applied Sciences. His master’s thesis examined the commercial potential of blockchain technology for German automotive companies.

Hans Hoefnagels is a member of the board of the eFuel Alliance and the Global Director of Public Policy at Horse Powertrain, a leading global innovation and manufacturing partner specializing in low-emission and alternative-fuel powertrain solutions. The company is at the forefront of delivering next-generation technologies that drive the global transition toward more sustainable and energy-efficient mobility. With over 15 years of experience in public affairs, Hans has held senior roles across both the public and private sectors. Prior to joining Horse Powertrain, he served as EU Policy Manager at Meta, where he led initiatives on digital policy and regulatory strategy. Earlier in his career, he was a Policy Advisor in the European Parliament. He holds a Master’s degree in Communication Studies from the Free University of Brussels. He is currently based in Madrid.

Arne Siemens is a member of the board of the eFuel Alliance. He studied environmental protection engineering at the University of Stuttgart and began his career in 2006 in the international trainee program at AUDI AG. He initially worked in development, focusing on vehicle dynamics, vehicle physics, and assistance systems. In 2016, he was appointed Technical Specialist at Audi AG. Starting in 2018, he was responsible for the power-to-liquid eFuels plant in Switzerland as project manager and subsequently coordinated eFuels development at AUDI AG. In 2023, Arne Siemens joined Porsche AG as project coordinator for eFuels and renewable energies. Since December 2024, he has been working as Lead System Engineer (LSE) Renewable Fuels at the Volkswagen Group.

Karsten Schulze, an automobile technician, was born in Berlin, managed a medium-sized bus and travel company for almost 30 years and has been a member of ADAC since 1982, with a brief interruption. Among other things, he was an honorary member of the presidium and the plenary assembly of the Berlin Chamber of Commerce and Industry and the German Chamber of Commerce (DIHK), was a member of the SME advisory board of the Federal Ministry of Economics, was active in the Federal Association of German Bus and Coach Operators e.V. and is currently a member of the advisory board of the Berlin Public Transport Company BVG AöR, board member for technology of ADAC Berlin-Brandenburg e.V. and board member of the eFuel Alliance. Karsten Schulze has been Technology President of ADAC e.V. since 2019. In his presidential honorary office, he is particularly concerned about affordable and safe mobility for all, the fair handling of our data, and a climate-friendly solution for internal combustion engines.

Photo: ©ADAC/Peter Neusser

Dr. Volkmar Pflug is Vice President Energy Economics at Siemens Energy and Field-of-Action Lead for Power-to-X. In his capacity, he is striving to make hydrogen and Power-to-X solutions and services a vital element of Siemens Energy’s business portfolio. One of the first project initiatives now under implementation, had been about eFuels. Before, he held various management positions in the power industry and IT industry.
Volkmar holds a Master degree in Physics, a Master degree in Business Economics and a PhD in Computer Science. He is a board member of the eFuel Alliance and of VDMA Power-to-X-for-Applications.

Sjur Haugen is a member of the Board of the eFuel Alliance and Director of Product Quality and Development at Circle K. He has over 35 years of experience in the energy and fuel sector. After completing his master’s degree in Maritime Administration at the Norwegian Business School in 1986, he joined Statoil ASA, where he held various positions until 2012. His roles included project economic analysis, market research on gas infrastructure, sales and market development for methanol and natural gas, as well as business development in renewable energy and biofuels. He also led the cooperation project between Statoil and UNIDO as part of the global “Access to Sustainable Energy for All” initiative. In 2012, Sjur Haugen joined Circle K as Head of Alternative Fuels. Today, as Director of Product Quality and Development, he is responsible for fuel product quality management across Europe and for the development and implementation of new fuel products and business models in the European organisation.

Mattias Goldmann has been elected Sweden's most influential in sustainability, he was knighted by the French President for his climate work and has won the lobbyist of the year award. He has been Chief Sustainability Officer of Europe's largest technical consultancy firm Sweco, CEO of Sweden's green and liberal think tank Fores, spokesperson for the Swedish Green Motorists and elected for office for the Green Party. He is the CEO of Goldmann Green and founder and spokesperson of the 2030-secretariat for a fossil independent transport sector. Mattias is Swedish, Geneva-born but lives in Bangkok where he is focusing on sustainable mobility. He is member of the board of the eFuel Alliance.

Tomas Malango is a BS in Chemical Engineering from the Universidad Complutense de Madrid, with postgraduate education in Advanced Management from IE Business School and Management of Research, Development and Technology Transfer from IESE Business School. Tomas Malango joined Repsol in 2001 at the Puertollano Refinery, where he was operation head in different areas before joining the Repsol Technology Center team as Senior Refining Technologist in 2008. Since then, Tomas Malango has managed different technology development projects for Refining and Mobility businesses at Repsol Technology Lab. He was also Hydrogen Director, responsible of creation and development of the renewable hydrogen strategy in Repsol. Since 2022 he is Director of renewable fuels and circular economy and also President of SHYNE (Spanish Hydrogen Network). He is member of the board of the eFuel Alliance.

Mr. Diomidis Stamoulis is Senior Director of Strategic Planning for Industrial Activities (Refining, Petrochemicals) and of Participations (in Electric Energy and Natural Gas) in the HELLENiQ ENERGY HOLDINGS S.A. Group. His role is focused on the group's transformation towards decarbonization by diversifying the industrial activities portfolio by gradually moving away from fossil sources, investing in new sustainable technologies developing new equity participations in clean energy. Prior to joining the HELLENiQ ENERGY HOLDINGS S.A. Group in 2008, he was employed by HELLENIC ASPROPYRGOS REFINERIES S.A., managing Production Planning and Optimization, and VIOHALCO S.A., the largest metallurgical industrial Group in Greece and Balkans, producing aluminum, copper, and steel products. He holds a MSc in Chemical Engineering from the National Technical University of Athens, a Ph.D. in Applied Thermodynamics from the Delft University of Technology and an MBA from the Athens Laboratory of Business Administration. He is member of the board of the eFuel Alliance.

Dr. Marco Warth is member of the board of the eFuel Alliance. He studied Mechanical and Process Engineering at ETH Zurich, where he received his Ph.D. in 2005 having worked on mathematical models and optimization of Diesel engines. 2006 he joined MAHLE in Stuttgart as a project manager in the corporate research and advanced engineering department. In 2010 he moved to Northampton in the UK and took over the responsibility for the product group Diesel within MAHLE Powertrain. From 2011 he was Engineering Director of MAHLE Powertrain Ltd. and responsible for all development activities. From 2014 until April 2021 he was heading up the corporate advanced engineering at MAHLE in Stuttgart and in charge of the transformation as key element of MAHLE’s “dual strategy”. Since May 2021 Dr. Marco Warth is responsible for the global product development engine systems and components at MAHLE.

Jürgen Roth is a board member of the eFuel Alliance and head of the newly founded eFuel Alliance Austria. He is Federal Chairman of the Austrian Energy Trade, Vice President of EuroCommerce, member of the Board of Verbund and member of the European Economic and Social Committee.. Jürgen Roth studied International Economics in the USA and Austria and has been working in the field of energy trading, logistics and gas stations since 1998. Since 2015 he is CEO and owner of Tank Roth GmbH.

Prof. Dr. Nicole Wermuth is the scientific director at the LEC GmbH and professor for “High-performance large engine systems” at the Graz University of Technology. Dr. Wermuth has a background in mechanical engineering and received her doctoral degree from the Technical University of Braunschweig. She worked as a post-doctoral researcher at the University of Michigan and later as a Senior Researcher at General Motors and at the GE Global Research Center. Prior to joining TU Graz, Dr. Wermuth worked at the LEC GmbH where she was leading the team “Combustion & Fuels”.

André Casal Kulzer is Professor at the Institute for Automotive Powertrain Systems, University of Stuttgart since January 2022. Prof. Kulzer received a MSc. degree in Mechanical Engineering from Technical University of Lisbon in 1999 and a PhD degree from University of Stuttgart in 2004. For his PhD thesis he received the TR100 Award in 2004 from MIT’s Technology Review - „one of the world’s top young innovators under 35“. After receiving is PhD he held the position of Senior Researcher and various Management positions at Robert Bosch GmbH in Schwieberdingen till 2011. From 2012 till 2021 he was Manager for Advanced Development Powertrain, together with Synthetic Fuels and Electrified Powertrain Concept Development at Dr. Ing. h.c. F. Porsche AG in Weissach.
His actual mobility research interests range from powertrain systems electrification, hybridisation, batteries, combustion concepts, zero emissions, hydrogen, E-Fuels, virtual development, artificial intelligence and Life-Cycle Assessment.

Tristan Brown, JD, PhD is full professor of Energy Resource Economics and Director of the Bioeconomy Development Institute at the SUNY College of Environmental Science & Forestry. He has authored over 60 publications and given over 90 talks at professional meetings on the subject of low-carbon fuels and products. He has led multiple large U.S. and private sector grants conducting research into the financial feasibility and climate impacts of low-carbon fuels and products. He served on the Energy-Intensive and Trade Exposed Industries advisory panel and Bioeconomy subgroup of the New York State Climate Action Council and contributed to the development of the Bioeconomy section of the New York State Climate Leadership and Community Protection Act’s Scoping Plan. He has also served as an expert witness in numerous legal and regulatory proceedings involving low-carbon fuels.

Professor Brown was awarded the SUNY College of Environmental Science & Forestry’s Exemplary Researcher Award in 2024 for his work on low-carbon fuels and is included in the Stanford University list of the top 2% of scientists in his field by annual and lifetime citations.

Dr. Michele Acciaro is an Associate Professor of Strategy and Innovation at Copenhagen Business School (CBS). He is an expert in sustainability, climate change policy, transport policy, and management. Previously, he served as an Associate Professor at Kühne Logistics University in Hamburg and as a Senior Researcher at Det Norske Veritas in Norway.

Dr. Acciaro has extensive teaching and supervisory experience and has received multiple awards for his outstanding academic contributions and teaching excellence. He is proficient in several languages, including Italian, English, German, Spanish, and Dutch.

Professor Bruna Rego de Vasconcelos is an Assistant Professor of Chemical and Biotechnological Engineering at Université de Sherbrooke. She earned her Ph.D. in Process and Environmental Engineering from École Nationale Supérieure des Mines d'Albi-Carmaux in 2016 and completed her postdoctoral studies at Université de Sherbrooke in 2019. Since 2019, she has been serving as an Assistant Professor, leading research projects on Power-to-X technologies, renewable energy, and biomass conversion. She has received several awards, including the Prix Jacques Bazinet for excellence in teaching. Her research focuses on catalyst development, life cycle assessments, and techno-economic analyses. Prof. Rego de Vasconcelos has published numerous scientific papers and actively participates in the academic community as a reviewer and member of various organizing committees.

Professor Yasushi Sekine is the Director of the Research Innovation Center and a Professor at the Faculty of Advanced Science and Engineering at Waseda University in Tokyo. He earned his Ph.D. from the University of Tokyo and has held various positions at Waseda University since 2001, including Assistant Professor, Associate Professor, and, since 2012, Full Professor. He has been recognized as a Fellow of the Royal Society of Chemistry and received the Science and Technology Award from the Japanese Minister of Education. Dr. Sekine has published over 227 scientific papers and serves as a Research Supervisor at JST-PRESTO and Principal Editor of the journal FUEL (Elsevier). His research focuses on heterogeneous catalysis, synfuel production, surface reactions, methane activation, and biomass conversion.

Univ.-Prof. Dr.-Ing. Ralph Mayer graduated in 2001 with a degree in engineering. He then worked as a research assistant at the Chair of Automotive Engineering at the Technical University of Munich from 2001-2007. In 2007-2014, he worked in chassis development at Daimler AG, Sindelfingen. Since 2014 he has held the professorship of vehicle system design at TU Chemnitz and since 2017 he has headed the µ-Club as a long-standing association of experts from industry and academia in the field of brake technology and has been involved in the program committee of several symposia. Prof. Dr. Ralph Mayer is a member of the eFuel Alliance's Sounding board.

Dr. Felix Leach is an Associate Professor of Engineering Science at the University of Oxford, and Fellow and Tutor in Engineering Science at Keble College. Heis a Chartered Engineer (MIMechE), a Fellow of the Higher Education Academy, and a Member of the Society of Automotive Engineers. His research interests are in combustion, and specifically emissions and efficiency in thermal propulsion systems. Felix’s work has focussed on, amongst others, fuel effects on combustion and emissions both in diesel and gasoline applications. He has a substantial ongoing interest in both bio- and e-fuels. He is the author of the book Racing Toward Zero: The Untold Story of Driving Green (SAE, 2021), which advocates for a life-cycle approach to rapid decarbonisation of transportation. Dr. Felix Leach is a member of the eFuel Alliance's Sounding board.

David Chiaramonti, PhD, is full professor of Energy Systems and Energy Economics at the Polytechnic of Turin and chairs the Renewable Energy Consortium for Research and Demonstration (RE-CORD). He authored over 180 publications and participated in over 27 research and development projects of the European Union. Mr. Chiaramonti is member of EUBCE (European Biomass Conference & Exhibition), ISAF (International Symposium on Alcohol Fuels), and ICAE International Conferences, he was former member of IEA-Bioenergy, Task 34 and Task 39 (Liquid Biofuel), and today member of UN-ICAO task force Fuel Transport Group on Alternative Fuels for aviation and ETIP-B. He was the scientific coordinator of the DG Energy Alternative and Renewable Transport Fuel Forum. He manages the H2020 projects BIO4A (on Sustainable Aviation fuels) and BIKE (on low ILUC feedstock biofuels), and is member of the Board of the Italian Cluster SPRING on Bioeconomy.

He was awarded the Linneborn Prize for outstanding merits in biomass at EUBCE 2017 in Stockholm, and included in the Stanford University list of 2% most cited scientists.

Kurt-Christoph von Knobelsdorff is a graduate economist and, following professional positions at the Association of the German Chambers of Industry and Commerce (DIHK) and the German Association of Family Businesses, he held senior positions in the Berlin Senate and the Ministry of Economic Affairs in Schleswig-Holstein. He was Head of Department at the Brandenburg Ministry of Energy and Managing Director at NOW GmbH. Mr von Knobelsdorff is member of the sounding board of the eFuel Alliance.

Prof. Dr. Bernhard Geringer is university professor for powertrain and automotive technology and director of the Institute for Powertrains and Automotive Technology at the Vienna University of Technology.  His research focuses on conventional and alternative powertrains, exhaust gas after-treatment, alternative fuels and forecasts of future vehicle technology considering the challenges confronting society today. Since 2012, he is member of the board of the Austrian Society of Automotive Engineers (ÖVK) and President since 2017.

Norbert Haug is a motorsport journalist. He spent more than two decades as motorsport manager and vice president at Mercedes and was responsible for the group's return to Formula 1, signing up motorsport greats such as Michael Schumacher, among others. Norbert Haug is a member of the sounding board of the eFuel Alliance.

Ralf Diemer is the CEO of the eFuel Alliance e.V. based in Berlin and Brussels. During his law degree in Tuebingen, he worked in the Baden-Wuerttemberg state parliament and in the European Parliament. He then started his professional career in Berlin as an office manager in the German parliament. After moving to the German Association of the Automotive Industry, he headed the Brussels branch there for ten years and then the department for Economic, Trade and Climate Protection Policy in Berlin. He was involved in numerous legislative processes on a national and European level, with a focus on climate, environmental and trade policy. Political interest and involvement in politics have always been of central importance to him. Ralf Diemer is Director at the consulting company von Beust & Coll. Beratungsgesellschaft.

Georg Ehrmann is a lawyer, CFO of the eFuel Alliance and since 2013 Partner of von Beust & Coll. Beratungsgesellschaft. Within the eFuel Alliance he is responsible for finance, press, human resources and legal affairs. For 13 years, Georg Ehrmann headed an international NGO that was based in Berlin and Brussels. Prior to that he was a legal advisor for a physicians' health insurance association. As an expert in UN and EU affairs and official adviser to the Federal Government, with numerous appearances before committees in the EU Parliament, Bundestag, Joint Federal Committee, and Landtag (state parliament), and as an expert in committees of inquiry, he has extensive experience in specific legislative procedures and political lobbying.

Dr. Tobias Block is an industrial engineer and Chief Strategy Officer at the eFuel alliance. He is an all-rounder when it comes to technical, economic and political challenges at the interface between renewable energies and the automotive industry. After studying energy and environmental management at the University of Flensburg he obtained his doctorate on eFuels business models at the University of St. Gallen. Following his studies, he worked for more than five years in the technical development department of AUDI AG. As the success of synthetic fuels depends more on the political framework conditions than on technical solutions, he joined the German Association of the Automotive Industry (Verband der Automobilindustrie e.V.) in the summer of 2018 and coordinated the political activities related to renewable fuels for more than two years – initially in Berlin and later from Brussels.

Lars Hummel is Head of EU Affairs at the eFuel Alliance e.V. in Brussels and responsible for the topics carbon management, energy taxation and financing. Before joining the eFuel Alliance e.V., Lars Hummel worked for Evonik Industries AG and the German Association of the Automotive Industry (VDA) in Brussels. He completed his master's degree at the University of Konstanz (MA Political and Administrative Science) and the University of Utrecht (MSc European Governance). He is a consultant at von Beust & Coll. Beratungsgesellschaft.

Tizian Lehnert is head of the Berlin office of eFuel Alliance e.V. and is therefore responsible for monitoring current political developments on the topic and representing the interests of eFuels at the German level. Tizian studied political science and economics with a focus on energy transition and climate policy. He previously worked for Continental AG and consulting agencies such as FGS Global. Tizian is a consultant at von Beust und Coll. Beratungsgesellschaft. 

Matthías Ólafsson is an Executive Consultant in the Brussels office of the eFuel Alliance. He has about a decade of experience in business development and government affairs. Before serving as an Executive Consultant for the eFuel Alliance and von Beust and Coll. Consultancy, Matthías held the role of Chief EU Representative of the global trade association of the methanol industry – The Methanol Institute (MI). Prior to joining MI, he performed several commercial functions at pioneering eMethanol producer Carbon Recycling International (CRI) leading efforts aimed at expanding sales and marketing capabilities and developing markets for renewable methanol. Matthías holds degrees in Political Science and Russian Linguistics of the University of Iceland.

Jan Wehrhold is Head of Press and Public Relations at the eFuel Alliance e.V. in Berlin. Alongside all the communications topics, he is responsible for the CO2 emissions standards for Heavy Duty Vehicles. Before joining the eFuel Alliance, Jan Wehrhold worked at DWReco and Medienbüro am Reichstag in the House of the Federal Press Conference. He graduated from Zeppelin University with a master's degree in politics, administration and international relations.

Ambroise Devresse is a management consultant at eFuel Alliance e.V. in Berlin. His work focuses on energy, climate, and mobility. Before joining eFuel Alliance, Ambroise Devresse studied economics and industrial economics at the Technical University of Berlin. He gained practical experience at HIF and the German Energy Agency.

Roman Verhaelen is a policy officer at eFuel Alliance e.V. in Brussels. He previously gained practical insight into EU institutions through his work at the European External Action Service in Brussels. Before that, he worked at the consulting firm PA Europe and in political energy monitoring at DeHavilland. He completed his bachelor's degree in European Studies at Maastricht University, including a semester abroad at the University of Hong Kong. He earned his master's degree in Transnational Governance with a focus on security studies at the European University Institute in Florence. 

Sabrina Piper has been working as a team assistant at the eFuel Alliance in Berlin since January 2026. She primarily provides support with administrative tasks and member management. She brings valuable expertise in administration, organization, and preparatory accounting through her many years of working in the people and culture sector.