Tools for Communicating the Nexus between Renewable Power-, Bioeconomy- and Circular Economies

Sankey diagrams have been essential for improving industrial processes' efficiency over the last century. Now it is time to advance this toolset to support efficiency improvements of the entire economic metabolism, including its interactions with the bio-, litho-, and atmosphere and between different sectors. In this paper, we propose and illustrate Sankey diagrams for the communication, comparison and discussion of synergies and trade-offs between anthropocentric transformation strategies regarding (1) renewable power, (2) circularity measures, and (3) the Bioeconomy. Therefore, this work brings together official and openly-accessible statistical representations of economy-wide energy, materials and biomass flows. The result is the first combined Eurostat derived database and Sankey diagram focusing on primary societal needs, circular flows and outflows, including emissions, landfilling and losses. Based on the presented advancements, we discuss major research gaps, including detailed resource flow accounts for other resources, including carbon dioxide, water, financial resources and labour. Next to missing resource flow accounts, novel indicators are also needed to address the broader economic metabolism's efficiency, with progress identified regarding non-equilibrium perspectives in metabolism modelling and Sankey illustrations. Finally, we stress the importance of overcoming barriers regarding accounting for stock accumulation and depletion for this tool set to support dynamic scenario analysis. Advanced Sankey diagrams will be decisive for quantitative approaches in transformation research, envisioning, illustrating, analyzing, and communicating transformation strategies to obtain the broader public's attention and necessary policies to implement them.