Consequence CO2 footprint analysis of circular economy scenarios in cities

Cities concentrate a large amount of people and activities thus being responsible for large amounts of resources being consumed which generate significant impact footprints contributing to climate change both directly and indirectly. In the meantime, circular economy is seen a promising concept to improve resource efficiency. Circular economy strategies are an emerging and important paradigm that can have an important effect in reducing CO₂ emissions.

This study aims at evaluating how circular economy strategies can reduce CO₂ emissions in cities with different contexts to find similarities and differences between them. The studied cities are Beijing, Shanghai, Vienna, and Malmö.

A scenario analysis study is done for two scenarios: 1) Business-As-Usual scenario (BAU) and 2) Circular Economy scenario (CE) from year 2017–2050, using multi-regional input-output (MRIO) analysis. The most CO₂-intensive Exiobase sectors associated with downstream consumption in households and government were identified as CO₂ emission hotspots, and emission reduction targets were identified and applied to these sectors.

The main results from the study show that although Vienna and Malmö have applied sustainability strategies for quite some time, the results do not show that CE strategies work better in the European cities compared with Chinese cities. The results also suggest that the greatest potential and effectiveness in reducing consumption lies in the sectors of energy use and materials consumption for all cities. It can also be seen that CE scenarios have higher potential for CO₂ emissions reduction when compared to the BAU scenarios but the reduction level in Shanghai and Malmö is weaker compared to Vienna and Beijing, which indicates the effectiveness of current CE strategies in reducing Beijing and Vienna's emissions. It also suggests that for Shanghai and Malmö, more ambitious CE strategies should be considered. Finally, comparing the distribution of emissions among the four cities it can be seen that consumption of Beijing, Shanghai and Vienna relies highly on domestic production whilst Malmö is more dependent on international production.