Bridging stakeholder perspectives through deliberation: A participatory approach to weighting decision criteria for seasonal thermal energy storage

easonal Thermal Energy Storage (STES) is central to the heat transition, but decision-makers must master a heterogeneous, highly context-dependent technology landscape. This study combines Constructive Technology Assessment (CTA) with elements of Multi-Criteria Decision Analysis (MCDA) to identify and weight 13 decision criteria for Seasonal Thermal Energy Storage. It examines how deliberative processes shift the perspectives of Selectors and Enactors. It is based on 19 expert interviews, two stakeholder workshops (n = 25 participants), and a pre/post survey. The results show that economic criteria dominate across all roles. Selectors systematically weight social aspects such as acceptance, space requirements, and visibility more heavily, while enactors place greater emphasis on technical criteria. It is also apparent that deliberation leads to noticeable shifts in weighting. The study thus makes three contributions: First, it demonstrates MCDA as a CTA platform for reflection and negotiation of conflicting goals. Second, it is the first MCDA application for STES selection with role-specific stakeholder weights. Third, it shows that the involvement of non-technical actors establishes MCDA as an instrument of participatory technology design and that technological assessments remain context- and perspective-dependent.