OLIVIER BAHN

Hydrogen in the Global Energy Landscape: Insights from Integrated Assessment Modeling

Abstract

As the world navigates the urgent need for a global energy transition, hydrogen emerges as a promising vector for achieving deep decarbonization. Evaluating the potential of a hydrogen economy requires a holistic perspective—one that captures the complex interplay between energy systems, land use, economic activity, and their associated greenhouse gas emissions. Integrated Assessment Models (IAMs) provide such a framework, combining insights across sectors to assess pathways toward climate goals.

This presentation provides a comprehensive survey of 12 integrated assessment model (IAM) families, synthesizing findings from 50 studies to evaluate hydrogen’s role across a broad set of scenarios featured in the IPCC Sixth Assessment Report (Working Group III). The analysis highlights hydrogen’s increasing importance, particularly in scenarios aligned with stringent climate mitigation targets. Moreover, the findings underscore that the extent to which hydrogen is deployed varies significantly across models, reflecting differences in structural assumptions, technology representation, and regional detail—emphasizing the critical influence of model design on projected energy futures.

In addition, we highlight ongoing developments at GERAD to expand our in-house IAM, AD-MERGE, through the launch of AD-MERGE-2.0. This updated version builds on its predecessor by incorporating improved geographic disaggregation—with six additional regions—enhanced technology representation, and updated assessments of climate damages and adaptation. Notably, it introduces a richer set of energy technologies, with particular emphasis on variable renewable energy systems and their integration. These advancements aim to improve the representation of hydrogen production pathways and deepen our understanding of its role in long-term decarbonization strategies.

Biography

Olivier Bahn holds an M.Sc. in Information Technology from the CNAM (France) and a Ph.D. in Management Science from the University of Geneva (Switzerland). Following his doctoral studies, he joined the Paul Scherrer Institute, a Swiss research center affiliated to the Swiss Federal Institutes of Technology, to lead several research projects on Swiss and European climate and energy policies. Since 2003, he has been a professor in the Department of Decision Sciences at HEC Montréal, where he was promoted to Full Professor in 2015 and chaired the department from June 2016 to May 2019. There he teaches graduate-level courses in management science. In addition to directing the Group for Research in Decision Analysis (GERAD, since June 2019), an inter-university research centre, he is also co-director of the e3c Hub (environment, energy and circular economy) at HEC Montréal (since June 2016). He serves as an Associate Editor of the journals Energies, Energy Strategy Reviews, and Environmental Modeling and Assessment. His research currently focuses on energy economics—particularly decarbonization—and climate policy modeling, with numerous publications in leading scientific journals. He is also a consultant for several companies, governments, and organizations.