Abstract
Municipalities play a critical role in driving sustainability transitions, but they often face significant challenges when considering complex and contested technologies such as waste-to-energy with carbon capture and storage (WtE-CCS). This paper examines the use of a citizen assembly as a deliberative democratic method for exploring sustainability transitions. The study pays particular attention to how knowledge is generated, deliberated, and managed throughout this participatory process. Drawing on deliberative democratic theory, the research conceptualises the citizen assembly not only as a participatory governance mechanism but also as a temporary knowledge intermediary that bridges expert, experiential, and institutional forms of knowledge. Empirically, the study is based on close, participatory observation of an actual citizen assembly process, and in-depth interviews with participants after the assembly. The analysis examines how various types of knowledge are utilised within the deliberative setting. It also explores how these knowledge practices influence participants’ understanding of the WtE-CCS technology specifically and of broader sustainability trade-offs more generally. This combination of observation and interviews provides rich insight into the assembly dynamics and how participants process and reflect on information together. The findings indicate that citizen assemblies can strengthen the reflexive capacity of municipal governance. Through the process, participants and organisers developed shared framings of the problem, and the assembly helped legitimise a diversity of knowledge claims. However, the study also notes tensions that emerged, such as questions pertaining to the mandate, the uncertainty inherent in new technologies, and the limited time available for deliberation. Overall, the paper contributes to the literature on sustainability transitions by highlighting the role of deliberative democratic innovations, such as citizen assemblies, in local knowledge management. It argues that well-designed citizen assemblies, which explicitly focus on the processes by which knowledge is generated and exchanged, can support more inclusive transition pathways at the local level.