CIRCULAR ECONOMY
What is the definition of a circular economy?
A circular economy is an economic system of closed loops in which raw materials, components, and products lose their value as little as possible, renewable energy sources are used and systems thinking is at the core.
Definitions often focus on the use of raw materials or on system change. Definitions that focus on resource use often follow the 3-R approach:
• Reduce (minimum use of raw materials)
• Reuse (maximum reuse of products and components)
• Recycle (high-quality reuse of raw materials)
Three elements
According to Korhonen, Nuur, Feldmann & Birkie (2018), definitions that focus on system change often emphasize three elements, which are further explained below:
• Closed cycles
• Renewable energy
• Systems thinking
Some researchers argue that social inclusiveness is also a necessary part of the circular economy (Korhonen, Honkasalo, and Seppälä, 2018).
How is a circular economy different from a linear economy?
A circular economy is fundamentally different from a linear economy. To put it simply, in a linear economy we mine raw materials that we process into a product that is thrown away after use. In a circular economy, we close the cycles of all these raw materials. Closing these cycles requires much more than just recycling. It changes the way in which value is created and preserved, how production is made more sustainable, and which business models are used. These aspects are explained in more detail below.
From eco-efficiency to eco-effectiveness
The perspective on sustainability is different in a circular economy than in a linear economy. When working on sustainability within a linear economy, the focus is on eco-efficiency. This is to minimize the ecological impact of the same output. This will extend the period in which the system becomes overloaded (Di Maio, Rem, Baldï, and Polder, 2017). Within a circular economy, sustainability is sought in increasing the eco-effectiveness of the system. This means that not only the ecological impact is minimized, but that the ecological, economic, and social impact is even positive (Kjaer, Pigosso, et al. 2019).
This difference can be illustrated by the production of beef. Raising cows for beef results in emissions of methane gas, a strong greenhouse gas. In a linear economy, the production of beef is made more sustainable by changing the way cows are fed, so that they emit less methane gas for the same amount of meat. This makes production more eco-efficient. In a circular economy, production is made more sustainable by not making beef from cows, but by imitating it as a meat substitute. For the beef substitute, plants are then grown that contribute to biodiversity, employment, and landscape management. In this way, the ecological, economic, and social impact of the same production of ‘beef’ is increased.
How do materials circulate in a circular economy?
In a circular economy, materials circulate in two separate cycles: the bio-cycle and the techno-cycle. The distinction between these cycles helps to understand how materials can be used in a long-lasting and high-quality way. A general rule of thumb is that the fewer process steps a material has to go through for reuse, the higher the quality of the material it can contain.
Technical and organic materials
Organic materials follow a different reuse process than technical materials. Technical materials are also called synthetic materials. Because of this difference in the reuse process, it is important that after use, organic and technical materials can be properly separated from each other after use.
Technical materials such as fossil fuels, plastics, and metals have limited availability and cannot easily be recreated. In the techno-cycle, it is important that stocks of such finite materials are properly managed. In a circular economy, these materials are only used instead of being consumed. After use, materials are recovered from residual flows at their original value.
Organic materials such as wood, food, and water can be incorporated into the ecosystem and re-generated through biological processes. In the bio-cycle, it is important to let the ecosystem do its work as well as possible. Consumption may take place during this cycle (fertilization, food, water) as long as the streams are not contaminated with toxic substances and ecosystems are not overloaded. Renewable organic raw materials can then be regenerated (Ellen MacArthur Foundation, 2015a).
Re-use in cascades
Within the bio-cycle, reuse takes place in cascades. Cascading means ‘using (part of) a product for another application’. When a product is no longer able to perform its initial function, it is passed on for reuse. During cascading, the quality of the material is reduced and energy is consumed (Ellen Macarthur Foundation, 2013a).
Cascading differs from ordinary reuse and recycling in that it changes function and the extent to which the product is processed. A cotton T-shirt can serve as an example. When reused, a worn T-shirt is sold in a second-hand shop. When recycled, the T-shirt is shredded into cotton fibers, which are then spun into new yarn. Cascading is the use of old T-shirts as cushion filling.
Long-term cycles
For both the bio-cycle and the techno-cycle, the lifespan of a product must be made as long as possible. The lifespan of products can be extended by:
• Ensuring that a product is used longer, thereby ‘slowing down’ the process, for example by focusing on emotional attachment to a product, lasting fulfillment of a need, and adaptability of the product, so that it can keep up with the times.
• To ensure that multiple consecutive cycles of direct reuse are followed, by facilitating the interchangeability of products and by properly maintaining products so that they can be used for a long time without repair (Ellen MacArthur Foundation, 2015a; Bocken, Bakker & De Pauw, 2015).
How does circularity relate to sustainability?
Circularity contributes to a more sustainable world, but not all sustainability initiatives contribute to circularity. Circularity focuses on resource cycles, while sustainability is more broadly related to people, the planet, and the economy. Circularity and sustainability stand in a long tradition of related visions, models, and theories. Here are some examples. In addition, we briefly explain how circularity fits in with the Sustainable Development Goals (SDGs) of the United Nations.
What are the disadvantages of the current linear economy?
The linear economy results from business practices that assume a constant supply of natural resources. This has resulted in the take-make-dispose mentality. This mentality is based on the extraction of resources, the production of goods and services, and the disposal of post-consumer waste. However, this approach is coming under increasing pressure because of its environmental and economic disadvantages.