Modular circular economy in energy infrastructures: The case of Small Modular Reactors

Policymakers, practitioners, and academics increasingly discuss modularisation and Circular Economy (CE) in the energy sector. However, these topics are usually discussed individually, failing to recognise their interdependency. Recognising interdependency is crucial because modularisation can become a key enabler of CE. This PhD research addresses this gap in knowledge. Traditional stick-built infrastructures have a lifecycle often predetermined by components very difficult or expensive to replace. Modular energy infrastructures could be made reconfigurable and extend their lifecycle by decoupling the life of the infrastructures from their modules. Modules can be designed in a way that, when a module reaches its end of life, it could be exchanged, extending the life of the infrastructure. Moreover, when the infrastructure needs to be retired, modules still functioning could be used in another infrastructure. Shifting the attention from component to module level can facilitate CE initiatives. Leveraging this intuition, this research investigated the link between modularisation and CE, focusing on the case of Small Modular Reactors (SMRs), which the literature considers a key modular technology in the next 10-20 years. This research contributes to both theory and practice. Regarding the contribution to theory, the link between modularisation and CE has been theoretically conceptualised by introducing the Modular CE, which is the key novelty of this PhD research. The Modular CE has been compared to traditional modularisation by leveraging a systematic review and a case study. Regarding the contribution to practice, this research focused on the reuse initiative, identifying and examining enabling factors and barriers for the Modular CE by interviewing 24 experts in the nuclear and oil and gas sector. Furthermore, this research identified and ranked the most relevant elements hindering and favouring Modular CE in the case of SMRs by conducting a questionnaire survey involving 97 SMR experts. Finally, this research paves the way to future research opportunities, such as investigating the Modular CE in other infrastructures (e.g. wind farm) and the quantitative evaluation of the economic and environmental implications of Modular CE initiatives.