Energy experts have been advocating for green hydrogen as an alternative to fossil fuels and a means to decarbonize heavily polluting industries. While green hydrogen is situated as part of global energy transition and climate mitigation processes, it is also guided by financial, geopolitical, and geoeconomic logics. Investigating how hydrogen projects are imagined and developed improves our understanding of how energy transition and climate mitigation are directed and how financial industries and geopolitical and geoeconomic relations inform them. This doctoral dissertation research project examines how experts situate this hydrogen technology within the broader context of energy transition and climate mitigation. The project trains a graduate student in methods of scientific data collection and analysis and builds capacity for the future conduct of scientific research in this setting. The findings of this doctoral research project are shared with a wide range of stakeholders, to improve the public’s understanding of science and the scientific method.<br/><br/>This project examines the relationship between energy transitions, speculative financial investment, and the transformation of geoeconomic relations. The researcher asks how policymakers, energy researchers, non-governmental organizations, and communities adjacent to hydrogen projects envision the impact of these projects; how financiers assess risk and opportunity in these projects; and what impact engineers and energy experts see hydrogen development having at different stages of the development process. The research takes place at a site where hydrogen development has rapidly emerged as a potential solution to regional decarbonization efforts. The research consists of a year of fieldwork at three sites, each representing a stage in the developmental chain (scoping, design, and implementation) for hydrogen technology. Methods include participant observation, semi-structured interviews, event ethnography, and document analysis. The findings of this research advance basic science within the fields of the anthropology of energy, social studies of climate finance, and anthropology of infrastructure and geopolitics.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.