Assessment of circular economy for global sustainability using an integrated model

The circular economy is increasingly gaining importance as one of the ways of transitioning towards a sustainable future. Assessment of the systemic effects of the circular economy on a global scale from a holistic perspective is the need of the hour. This work addresses this challenge and models the circular economy in a planetary model with integrated human, ecological and industrial components. The circular economy is modelled as an industry which processes the used industrial goods. These are used along with the goods produced using virgin raw materials. Different time delays and circulation rates parameterize 90 different routes of implementation of the circular economy. These are implemented for nine levels of resource consumption increase by humans complemented by population growth. System collapse due to the scarcity of ecosystem based resources occurs sooner as the consumption level increases. Model simulation results indicate substantial benefits of adopting the circular economy. Incorporation of circular economy delays the system collapse by at least a few decades and aggressive implementation of the circular economy, in several cases, avoided this collapse entirely. Based on these results, the time horizon of the next 70 90 years is identified as critical, before which a large scale implementation of the circular economy is essential. However, very aggressive implementation of circular economy leads to system collapse because of the depletion of common access ecosystem services caused by continued high consumption. Thus, this work establishes benefits of the circular economy and recommends a balanced approach for the adoption of the circular economy.