Integrated Assessment of the Role of the Circular Bioeconomy in Climate Change Mitigation: The Case of Plastics

Next to the use of biomass, also the contribution of a circular economy to climate change mitigation are increasingly discussed. The concept of a circular bioeconomy (CBE) has found its way into European bioeconomy strategies. So far, the benefits and drawbacks of (biomass) cascading and recycling, key elements of a CBE, have only been assessed in life-cycle based case studies. Assessing cascading and recycling in integrated assessment models (IAM) offers a dynamic, long-term perspective and show aggregated effects. Using an IAM and plastics as an example, the goal of this paper is to assess if, to what extent, and under which circumstances biomass use in combination with recycling & cascading could lower the emissions of the chemical sector and improve the climate change mitigation potential of the bioeconomy up to 2050. Our results show global projections of plastics demand, their production pathways and end-of-life strategies according to different socioeconomic pathways and policy scenarios. We compare the results regarding their GHG-emissions, land-use change and economic costs and discuss potential preferences for certain biomass end-uses & end of life options.