Circular decarbonisation? Material and waste implications of the transition to low-carbon technologies in Switzerland

This study examines the critical raw material (CRM) demand of the transition to photovoltaic panels, electric vehicles and wind turbines in Switzerland. We take a bottom-up dynamic stock modelling approach to calculate current stocks and project in- and outflows until 2050. Waste flows are projected to increase six-fold in the following five years, from 980 tons (2020–2025) to 6200 tons (2025–2030). In 2050, decommissioned stock could theoretically meet 85% of annual CRM demand. We explore the impacts of circular economy practices such as repair, reuse and diversification, and find that a combination of longer technology lifespans and increased local recycling capacity are necessary to reduce the pressure on demand for CRMs. Policies to ensure a sustainable energy-mineral nexus in the built environment will therefore benefit from supporting local recycling infrastructure and (re)manufacturing capacity, and encouraging regulatory frameworks for quality assurance, product warranties, and acceptance of repaired products. Our study highlights that a holistic energy strategy needs to consider the underlying material cost of powering the built environment.