Abstract for: Exploring policy mixes for the decarbonization of the Swiss residential sector: a hybrid System Dynamics approach

Decarbonizing the residential sector requires the coordinated diffusion of multiple technologies and policies within complex socio-technical systems. Traditional modelling approaches often capture either household heterogeneity or system-level dynamics, but rarely both. This limits the ability to analyze how policy mixes shape technology adoption, energy demand, emissions, and distributional outcomes during the energy transition. This study develops a hybrid system dynamics model of the Swiss residential sector that integrates micro-level adoption decisions with macro-level system feedbacks. The building stock is represented through 8,580 archetypes where households adopt photovoltaic systems, heating technologies, and building retrofits using discrete choice formulations. An exploratory analysis of 1,500 simulations examines alternative policy mixes under techno-economic uncertainty. The scenario ensemble reveals substantial variability across policy configurations. Regulatory measures and higher CO₂ tax levels are strongly associated with lower cumulative emissions and reduced heating demand. Stronger incentives accelerate photovoltaic deployment but tend to increase inequality linked to electricity levies. The results highlight trade-offs between decarbonization, technology diffusion, energy efficiency, and distributional outcomes. The findings emphasize the importance of coherent policy mixes and institutional design in shaping residential energy transitions. In particular, policy financing mechanisms influence not only technology adoption but also the distribution of costs and benefits. Hybrid simulation models provide a useful framework for exploring these interactions and supporting evidence-based policymaking under deep uncertainty.