Applying system dynamics sustainability assessments (SDSA) to assess circular economy solutions in cities and regions – 09.06.2025

Life Cycle Sustainability Assessment (LCSA) has seen an increasing uptake in the past years, promising a comprehensive assessment of sustainability over the life cycle, with a consideration of environmental, economic, and social impacts. And yet, a linear life cycle model as used in LCSA struggles to reflect some key concepts of sustainability, including thresholds and possible non-linear system behaviour, as well as system transition scenarios. With these limitations, LCSA has often failed to capture the true enablers and benefits of circular economy (CE) solutions.

In the EU-funded Horizon project TREASoURcE, a novel sustainability assessment approach that combines system dynamics and LCSA, namely system dynamics sustainability assessment (SDSA), was developed and applied. This approach was developed to overcome limitations of LCSA, while offering a practical modelling and assessment approach for stakeholders in CE decision-making positions. It comprises of two linked parts: (1) a system dynamics model that includes market data and context indicators that influence system behaviour, and (2) a prospective LCA model, implemented in openLCA, that calculates environmental impacts over time.

A case study application for plastic value chains in Gothenburg, Sweden, has now led to some interesting results. By including context indicators, such as infrastructure accessibility, technology adoption, and regulatory support, and simultaneously calculating environmental impacts, further insights into the feasibility of certain CE solutions for specific regions emerged. Four different scenarios were simulated and it was found that increasing impulses for consumer awareness and subsidising circular plastic solutions was the most effective scenario for the region.

The graph here shows the climate change impact over time of the region linked to high density polyethylene (HDPE) value chains. Through a wider implementation of circular economy strategies, the climate change impact decrease over time.

The graph shows the depletion of fossil resources over time. The decline slows and eventually flattens for the scenarios that take on circular economy solutions for plastics. These are preliminary results, but the new sustainability assessment approach is already showing that it essentially has the potential to support cities and regions in setting up suitable and effective CE strategies.

9.6.2025 | Alexander Koch (GreenDelta)

For more information, contact: koch@greendelta.com