Circular economies usually focus on a specific technology dealing with an individual resource flow. At the scale of a city, the required governance and policy decisions, as well as the relevant evidential data to underpin those decisions, have not been explored so far. Even though individual resource streams may have rich data associated with them and a variety of techniques can explore the economic and environmental impacts of altering these resource flows, it is not clear how these distinct streams of analysis can be combined to develop a truly integrated understanding of what a city-scale circular economy means.
This project has generated a method for systematically identifying opportunities that would increase the circularity of a city’s economy. This method uses a novel conceptual framework that combines the ideas of the circular economy with the principles of the waste hierarchy, all with a spatial constraint. Through qualitative interviews of experts, purposive and snowball sampling and quantitative data analysis, eight types of dataset and four aspects of governance or decision-making support have been identified as essential for systematic city-scale circular economy action (called the 8+4 framework, for short). The City of Leeds was used in a case study for testing the 8+4 framework. We identified areas of good practice and suggested city-specific opportunities, building on grassroots activity and social enterprises, as well as the requirement to develop a coherent, city-wide policy framework.
No city has been identified that tackles the opportunities of the circular economy on a systematic, city-wide basis.
A global review of circular economy activities revealed 78% focussed on a technology or tackling a specific resource flow and lacked a spatial component. The remaining 22% of projects were identified as potentially 'city-scale' due to their explicit connections with city actors.
There is a focus on the technological processes involved in solving waste problems. However, there are not many examples of cities and other governing bodies investing in these processes to increase the overall size of the circular economy in particular locations. Waste to energy installations remain the most common circular economy process.
A coherent policy framework is important to the implementation of circular economy principles as it helps establish a platform for circular economy actions to be discussed and provides the impetus some actors may need to pursue circular waste interventions.
Linking the circular economy and the waste hierarchy is, as far as our research was able to determine, a novel approach to implementing a city-scale circular economy. The conceptual model developed could provide the basis for engaging cities in thinking through circular economy actions and impacts within theory boundaries. The outcomes of this project enable us to enhance our circular economy offering for cities by adopting the most suitable route – which is determined based on the identified challenge. The responsive, technology-facing route can be applied if a city is motivated to tackle a challenge regarding a particular resource. If the starting point is the policy framework and stakeholder engagement, a system-changing route is to be used. Each of the routes envisages provision of specific services, putting emphasis on the features specific to a challenge.
Categorising circular economy actions according to waste hierarchy principles enables a more systematic approach to developing a circular economy which delivers across social and economic impacts as well as environmental benefits. The opportunities for social enterprise and economic opportunities through small-scale or site-specific activity becomes clearer when the step-wise model is used. Through this research we managed to identify the knowledge gaps that need to be filled if the vision of a circular economy on a city scale is to be realised. These gaps can contribute to the formation of the next wave of research and collaboration that will help Arup stay at the forefront of circular economy developments.