Paper short abstract:

Nuclear fusion R&D inevitably embraces a long-term future vision up to the next century. Based on empirical research on the ITER project, this paper explores how imaginaries and promises formulate a pathway and interact with materialities so that the uncertain future acts as “real”.

Paper long abstract:

Nuclear fusion energy has (re)gained huge attention in recent years due to the urgent necessity to tackle climate change and the energy crisis. While its potential as “ultimate energy” with virtually limitless resources and low-carbon emissions attracts both private and public investment in research and development of the technology, the realisation of a commercial fusion reactor in the upcoming decades remains uncertain due to technical feasibility. By focusing on ITER, the largest international nuclear fusion experimental reactor project, this paper explores the formulation of promissory narratives for the future-oriented technological development. It employs perspectives and concepts in science and technology studies (STS) and assesses how sociotechnical imaginaries are embedded in technology development and how promissory discourse enacts as justification against uncertainties in the discourses and practices. The empirical study with expert interviews, critical document analysis, and online and onsite ethnographies shows that visions are materialised through experts’ proactive practices in the form of documents (i.e. roadmap, policy and legal documents) that play performatively and reflectively as a reference point. The study unveils how languages, representations, and materialities collectively and complementarily (and sometimes contradictorily) shape the legitimacy of future technology. This paper contributes to the scholarship on the critical assessment of techno-futuristic visions and reflects on their impact on future-making practices for sustainability and energy transition.