Implementing a Circular Economy at City Scale – a challenge for data and decision making, not technology

The circular economy currently receives considerable attention as policy outcome or design intent, with the main focus on how to close resource flow loops, tackled as a problem for technologies to solve. This builds on academic literature of resource efficiency and in particular the concept of an ‘urban metabolism’. Closing resource loops is rarely presented alongside spatial analysis but as cities are significant sites of concentrated resource use, spatial considerations need to be introduced to the discussion of the circular economy. This paper presents a process for identifying circular economy actions which can be deployed at the city scale. Without preferring particular technology solutions, we propose a systematic process identifying options for re-use and recycling before investing in material transformation and energy recovery. At each stage of the process there are different requirements for data, and for governance structures. The process was developed and tested using the city of Leeds as a case study. Datasets for waste, water, energy (electricity and heat) and other resources (e.g. land) were identified and analysed. We found that the barriers to increasing circularity are twofold. First, consistent, coherent and congruent datasets describing resource flows are not available. Second, there is no (or not enough) citywide capacity to ensure circular economy actions are systematically implemented to realise the social, environmental and economic potential of the circular economy at city scale. The paper does not advocate gathering more data or creating complex models. Instead we suggest three foundation datasets and two governance factors which need to be in place to create a platform for the city-scale circular economy to be developed. Once this platform is established, five further datasets and two more governance factors help shape plans for effective implementation of the circular economy opportunities which the city-scale process helped to identify.