Do We Need a New Sustainability Assessment Method for the Circular Economy? A Critical Literature Review

Abstract

The goal of the circular economy (CE) is to transition from today's take-make-waste linear pattern of production and consumption to a circular system in which the societal value of products, materials, and resources is maximized over time. Yet circularity in and of itself does not ensure social, economic, and environmental performance (i.e., sustainability). Sustainability of CE strategies needs to be measured against their linear counterparts to identify and avoid strategies that increase circularity yet lead to unintended externalities. The state of the practice in quantitatively comparing sustainability impacts of circular to linear systems is one of experimentation with various extant methods developed in other fields and now applied here. While the proliferation of circularity metrics has received considerable attention, to-date, there is no critical review of the methods and combinations of methods that underlie those metrics and that specifically quantify sustainability impacts of circular strategies. Our critical review herein analyzes identified methods according to six criteria: temporal resolution, scope, data requirements, data granularity, capacity for measuring material efficiency potentials, and sustainability completeness. Results suggest that the industrial ecology and complex systems science fields could prove complementary when assessing the sustainability of the transition to a CE. Both fields include quantitative methods differing primarily with regard to their inclusion of temporal aspects and material efficiency potentials. Moreover, operations research methods such as multiple-criteria decision-making (MCDM) may alleviate the common contradictions which often exist between circularity metrics. This review concludes by suggesting guidelines for selecting quantitative methods most appropriate to a particular research question and making the argument that while there are a variety of existing methods, additional research is needed to combine existing methods and develop a more holistic approach for assessing sustainability impacts of CE strategies.

The Circular Economy Lifecycle Assessment and Visualization Framework: A Case Study of Wind Blade Circularity in Texas

“…As of 2020, commercial recycling technologies exist for approximately 85% by mass of the materials used in wind turbines in the United States. Blade materials, particularly the glass and carbon fiber reinforced polymers that form the bulk of blade materials, are the exception (Razdan and Garrett, 2019;Vestas -Sustainability Report, 2019). Many of the wind turbine blades in use as of 2020 are made from glass fiber reinforced polymer (GFRP), whereas newer and future turbine blades are more likely to be made from carbon fiber reinforced polymer (Hao et al, 2020;Wood, 2020) or from thermoplastic composite (Murray et al, 2019(Murray et al, , 2021.…”

“…Anticipating and accounting for potential negative impacts-environmental, economic, social, and others-in the decision-making processes that drive circularity transitions will decrease the likelihood of unintended consequences and provide a more complete picture of circularity transition impacts (Corona et al, 2019;Helander et al, 2019). We posit that a circularity transition represents a fundamental, systemic, dynamic shift in supply chain and economic structure, and that adequately modeling and assessing the impacts of a circularity transition in order to inform related decisions therefore requires capabilities beyond what any single previously developed method offers (Walzberg et al, 2021).…”

“…The level of aggregation of CGE models thus limits their utility for analyzing systems during a circularity transition. Partial equilibrium (PE) models, which capture a sub-set of economic sectors in greater detail than CGE models, offer less aggregation than CGE along with a much FIGURE 1 | Summary of the scope (A,C) and capability (B) requirements for modeling circular economy transitions, building on an analysis of circularity methods in Walzberg et al (2021). Capabilities of existing modeling methods are shown in blue ovals, while CELAVI capabilities are indicated with orange rectangles.…”

Integrating sociotechnical factors to assess efficacy of PV recycling and reuse interventions

“…However, current studies of material circularity are limited to technical and economic material efficiency potentials and do not account for consumer behavior 13,15 . This assessment means that major changes in the way CE is analyzed need to be undertaken 12,16,17 .…”

“…We apply a novel agent-based model (ABM) to represent multiple actors involved with the PV life cycle as well as social factors (attitude and peer influence) constraining CE strategies and build a machine-learning (ML) metamodel to conduct a global sensitivity analysis. An ABM is well suited for studying the CE transition because it considers temporal aspects, adopts a systemic view, and accounts for human decisions and interactions between actors 16 , exploiting recent advances in behavioral economics and psychology 16,[18][19][20] . ABMs have been used to study CE scenarios in relation to waste management [21][22][23][24] , but no previous model has included secondary market dynamics underlying the reuse CE strategy.…”