Circular Economy Strategies and the Battle Against CO2 Emissions in Cities

Introduction

Cities are hubs of human activity, drawing large populations and consumption patterns, making them significant contributors to resource consumption and, consequently, climate change. The growing urbanization trend places an ever-increasing burden on the environment, making it imperative to rethink how urban centers can operate more sustainably. Circular economy strategies are emerging as a promising approach to enhance resource efficiency and reduce the carbon footprint generated by cities. This study delves into the role of circular economy strategies in mitigating CO2 emissions in four diverse cities: Beijing, Shanghai, Vienna, and Malmö.

Circular Economy and its Potential

The circular economy, an economic model designed to minimize waste and make the most of available resources, is gaining traction as a solution to address climate change. In essence, this concept promotes a sustainable, cyclical approach to production, consumption, and waste management. By keeping products and materials in circulation for as long as possible and reducing waste, circular economy strategies have the potential to significantly reduce carbon emissions.

Methodology and Scenarios

This study employs a scenario analysis using two primary scenarios: the Business-As-Usual (BAU) scenario and the Circular Economy (CE) scenario, spanning the years 2017 to 2050. The analysis relies on the multi-regional input-output (MRIO) method. To identify CO2 emission hotspots, the study focused on the most carbon-intensive sectors in the Exiobase database associated with downstream consumption in households and government. Emission reduction targets were established and applied to these sectors.

Key Findings

1. European vs. Chinese Cities:

   Contrary to the expectation that European cities with well-established sustainability strategies would outperform their Chinese counterparts, the results suggest that CE strategies do not show a significant advantage in Vienna and Malmö compared to Beijing and Shanghai. This finding underscores the need for tailored, context-specific approaches to address CO2 emissions in cities.

2. Energy and Materials Consumption:

   Across all cities, the sectors of energy use and materials consumption emerge as pivotal areas for CO2 emissions reduction. This emphasizes the importance of prioritizing these sectors in any circular economy strategy aimed at mitigating emissions.

3. Effectiveness of CE Strategies:

The study reveals that CE scenarios exhibit a higher potential for CO2 emissions reduction compared to BAU scenarios in all cities. However, the extent of reduction varies between cities, with Vienna and Beijing demonstrating more effective CE strategies compared to Shanghai and Malmö. This discrepancy highlights the need for more ambitious circular economy initiatives in certain contexts.

4. Production Dependency:

   A notable distinction among the cities is the distribution of emissions concerning domestic and international production. While Beijing, Shanghai, and Vienna rely heavily on domestic production for consumption, Malmö exhibits a higher dependency on international production. This variance underscores the importance of considering global supply chains when implementing circular economy strategies.

Conclusion

As cities grapple with the challenges of climate change and resource scarcity, the adoption of circular economy strategies emerges as a promising approach to mitigate CO2 emissions. This study highlights the complexity of the urban landscape, demonstrating that the effectiveness of CE strategies is not solely dependent on geographical location or sustainability history. Instead, the focus should be on tailoring strategies to target the most carbon-intensive sectors – energy and materials consumption – and recognizing the importance of international production dependencies. This research provides valuable insights into the potential of circular economy strategies in different urban contexts, paving the way for more sustainable, eco-friendly cities worldwide.

References:

Yiwen, Liu., Leonardo, Rosado., Nelli, Melolinna., Johan, Holmqvist., Brian, D., Fath. (2023). Consequence CO2 footprint analysis of circular economy scenarios in cities. Cleaner production letters, 100045-100045. doi: 10.1016/j.clpl.2023.100045