Circular Urban Metabolism Framework

Abstract

In our cities, the production and consumption of resources are achieved at an unsustainable rate. Combined with an increasing global population and accelerating urbanization, the absence of a new approach will almost certainly have dramatic environmental consequences. Potential solutions are emerging: the concepts of circular economy (CE) and urban metabolism (UM), which contrast the current and traditional linear extract-produce-use-dispose model of the modern economic and urban systems, offer a new approach. In this Primer, we present the principles of CE and UM as well as their origins and definitions, strengths and weaknesses, similarities, and limits. We introduce how these concepts can be used for designing a new urban framework called circular urban metabolism (CUM), which encourages urban planners and decision makers to study, design, and manage sustainable cities. CUM has the potential to unite research fields to promote collaboration across disciplines that operate on the planning, design, and management of cities and their complexities.

Seeking Circularity: Circular Urban Metabolism in the Context of Industrial Symbiosis

“…Aguledo-Vera et al [110] briefly discussed the CUM concept, but they conceptualized the main framework of the CUM in the context of the city-low consumption rate, recycling and reuse of the different urban flows, with less impact on hinterlands and other cities. A recent publication of Lucertini and Musco [111] presents a framework of CUM by integrating CE and UM principles to simplify the complexity of the city to facilitate the assessment of urban complexity and the implementation of a sustainable urban vision [111]. In other words, CUM could be explained as a recognition of the city's material and energy outputs as recycled inputs [105,112], while city's relationship with his hinterlands and other cities was excluded.…”

“…Lucertini and Musco [111] proposed CUM framework builds on the combination of the 3R framework developed by CE and UM as an urban ecosystem. CUM framework helps to understand, how urban flows interact with the environment and ecosystems within and outside the city.…”

“…CUM has the potential to maximize co-benefits, evaluate the effectiveness of land use, re-project infrastructure use, and improve cities' ability to respond to climate change. CUM implies CE principles in the city level with the connection of flows, rethinking urban activities, redesign social and urban infrastructure, reduction and recovery of resources [111]. However, Lucertini and Musco [111] proposed CUM framework, which does not include hidden flows impact analysis to urban ecosystems.…”

“…CUM implies CE principles in the city level with the connection of flows, rethinking urban activities, redesign social and urban infrastructure, reduction and recovery of resources [111]. However, Lucertini and Musco [111] proposed CUM framework, which does not include hidden flows impact analysis to urban ecosystems. Hidden flows can be understood as flows included in goods and services city consume or produce [101,113] and are not visible in economic records, trade and production statistics.…”

“…Hidden flows can be understood as flows included in goods and services city consume or produce [101,113] and are not visible in economic records, trade and production statistics. It reflects that modern cities can significantly reduce the direct material and energy flows, but can remain intensively dependent on material and energy intensive processes and services elsewhere [111,113]. Generally, hidden flows consist of secondary energy consumption in processing products or services.…”