Designing circular resource flows in European cities

A blueprint for the management of critical urban flows to fast-track the transition toward circular and regenerative cities.

In this project, spanning three years and six cities, the Metabolic Institute explored how key material flows such as plastics, textiles, organic waste, and construction materials move through urban landscapes. Once these flows are clearly mapped and their environmental hotspots understood, an exciting array of circular innovations and strategies came forth to reconfigure them and strengthen the participating cities’ regenerative capacities. 

Many cities across Europe are aiming to become truly circular, not just by recycling  the resources available from waste materials, but also by changing their production modes and optimising materials’ flows. The EU-funded REFLOW project developed innovative tools and guidelines to help them achieve this goal. The work will support greener cities for citizens. 

  • Funder: EU Horizon 2020
  • Grant Agreement: N°820937
  • PartnersCopenhagen Business School, Dyne, IAAC, Waag Society, Ecovala, Gemeente Amsterdam, Commune de Paris, Comune di Milano, Kommune Vejle, Municipul Cluj-Napoca, Senatskanzlei Berlin
  • Participating Cities: Amsterdam, Berlin, Cluj-Napoca, Milan, Paris, and Vejle
  • Date: July 2019 – August 2022

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 820937

The challenge

Cities account for 3% of the total land surface of the planet, yet use 75% of the total resources extracted by the world’s economy. They are responsible for three quarters of global consumption, the vast majority of which is produced outside the urban boundaries. With 68% of people projected to live in cities by 2050, their size and economic impacts are expected to grow. Reducing urban waste and environmental impacts has become both a priority and a key leverage to transition the economy into a regenerative and circular state.

The challenge
Our approach

Metabolic Institute applied Material Flow Analysis to understand and trace the metabolism of six European cities. Practically, this tool enables the assessment and modeling of the materials, energy, water and waste that move into, out of, and within a city. In each REFLOW pilot city, we assessed critical urban resource flows including plastic, textile, organic waste, timber and energy. We identified the major environmental hotspots caused by these flows and offered interventions aimed at reducing their negative impacts. The social-cultural, environmental, and economic context of cities and their stakeholders act as leading lights for how we guided the reconfiguration of these resources flows and intervened effectively in each pilot city. 

Our team was also involved directly in the Amsterdam pilot, working to find smarter local and regional ways to reuse textiles in a way that embodies circular thinking and achieves financial viability. 

Our approach
The outcome

REFLOW offers a new strategic vision for circular and regenerative cities, and provide tangible and tested blueprints on how to reconfigure urban metabolisms while catering to the needs of citizens as well as public and private actors. The social, environmental, and economic impacts of the interventions implemented in each pilot was closely monitored for the duration of the project. REFLOW provided critical insight on circular urban resource flows, and the conditions required for circular innovations to flourish in European cities. The project presents real-life and open-source examples, tools and learnings which can be widely applied to other existing urban contexts. Some examples include:

Results of the project in Milan produced BOTTO – an automated communication system that facilitates the reallocation of surplus food. It enables close cooperation between fruit/vegetable wholesalers and associations working against food waste or helping people in need. 

The REFLOW OS – an operating system designed specifically for communities who want to create federated and secured economic networks across a value chain  helps incentivise circular practices in local ecosystems by monitoring and optimising urban metabolic processes. 

In Cluj-Napoca, the REFLOW Knowledge Hub provides essential resources to those interested in energy saving. In Amsterdam, participants worked on denim supply chain sustainability by making post-consumer recycling the industry standard. In Berlin, they focused on wastewater heat: partners developed an app in the style of a radar to map wastewater heat supply and demand while connecting suppliers with users. In Vejle, the Value Chain Mapping Game helped outline the whole value chain flow of retail plastic through gamification. 

These, along with the rest of the innovations developed in each pilot city, provide inspiration to other cities and their citizens to take action and embrace the circular economy.  

The outcome
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