Heat pumps are a low-carbon alternative to conventional fossil fuel-based heating systems, yet their adoption in the Netherlands remains limited. To better under-stand heat pump adoption dynamics, we propose an integrated behavioral frame-work that combines the Capability-Opportunity-Motivation-Behavior (COM-B) model with the HUMAT modeling framework. This integration translates behav-ioral theory into an agent-based modeling structure that captures how heterogene-ous household characteristics, social interactions, and economic conditions shape adoption decisions. A household survey was conducted to calibrate household characteristics, and the model was further calibrated and validated using historical Dutch and Swedish adoption data. Results show that adoption dynamics are highly sensitive to behavioral assumptions, with different decision-making im-plementations producing substantially different outcomes. Scenario analysis indi-cates that adoption is primarily constrained by Capability and Opportunity rather than Motivation alone.

This work-in-progress paper studies whether prior carbon pricing changes the heating stock in ways that reduce households' exposure to later fossil fuel price shocks. It develops an agent-based model of residential heating choice with heterogeneous households, replacement cycles and failures, financing constraints, liquidity lock-in, and an unanticipated persistent gas/oil price shock. The current paper uses a synthetic household population designed to resemble the German 2018 Income and Expenditure Survey (IES), because the licensed microdata are not yet available for this submission. Across two background price environments, prior carbon pricing increases pre-shock low-carbon adoption and thereby reduces the incremental policy-adjusted burden caused by the later shock. The protection effect also lowers energy poverty and appears across all income quintiles, with larger gains in the lower part of the distribution. These findings are preliminary and should be read as mechanism evidence rather than representative estimates, but they suggest that the social evaluation of carbon pricing should account not only for contemporaneous burden but also for how policy changes future shock exposure.

The transition from a linear “take–make–dispose” economic model toward a circular economy poses a strategic challenge for firms seeking to reconcile environmental sustainability with economic performance. Although circular economy principles promise reductions in resource use and waste generation through recycling and product redesign, their economic feasibility remains debated, particularly for firms transitioning from linear production models. Moreover, the role of downstream actors—especially users—has emerged as a critical yet insufficiently explored determinant of circular economy outcomes.

This paper investigates the economic feasibility and transition dynamics of circular production by developing an agent-based simulation model of an interconnected supply chain composed of suppliers, manufacturers, users, and recyclers. The model explicitly represents material flows, pricing and inventory mechanisms, and user purchasing behavior. To disentangle interaction and aggregation effects from ex ante heterogeneity, we consider a multi-agent setting in which multiple agents operate within each functional category, while manufacturers adopt a common circular strategy—defined by the share of recycled material used in production—and users share a common sentiment toward circular products. A systematic computational experiment explores different combinations of circular strategies and user sentiment under varying cost conditions.

The results show that manufacturers’ economic performance is jointly shaped by circular strategies and user sentiment. Mixed production strategies combining virgin and recycled materials consistently outperform both purely linear and fully circular configurations across a wide range of scenarios. Full circularity rarely emerges as the economically optimal outcome, whereas the coexistence of linear and circular production constitutes a stable system-level regime. Furthermore, user sentiment significantly affects not only profitability but also the temporal dynamics of the transition toward circular production, exerting a stronger influence than upstream cost structures.

By highlighting demand-side behavior, interaction effects, and temporal dynamics, this study contributes to a system-level understanding of circular product innovation and its economic viability.