The Circular Economy and Embodied Carbon, two sides of the same coin

Theo Meslin, Sustainability Consultant, Longevity Partners

Circular Economy is a principle that has long existed but has only recently gained popularity. In fact, one could argue that the concept has always existed, since circularity is an inherent principle upon which nature itself is based. What is born from the Earth, eventually returns to the Earth. From “ashes to ashes, dust to dust”.

The concept of circularity as a design principle has also become widespread in recent years and has even been integrated into policy. This is the case with the Greater London Authority (GLA) requiring major developments to provide a “Circular Economy Statement”, explaining how circularity was considered during the design stage [1] and implemented during construction. Some key examples of circularity and circular design can be found in methodologies such as “cradle to cradle”, which has been previously discussed in this Longevity article, outlining the key pillars of this methodology and explaining how it relates to the circularity and the benefits it brings.
This article will explore one of the “hottest” topics (pun intended) that is looming over us all: global warming. Indeed, as the title of this article implies, the Circular Economy and Embodied Carbon are inextricably linked.

 

But what is Embodied Carbon? And why does it matter?

To put it simply, Embodied Carbon represents all the carbon emissions caused by a product that are not directly linked to its use. In the case of a building, while the focus often lies on the carbon emissions caused by its operation and energy use, embodied carbon looks at the carbon emissions that are generated by the production of the building itself. This covers the extraction of the raw materials that are used, their transportation to a manufacturing facility, their processing into specific products, the transportation of the products to the construction site, and the construction process itself. Embodied Carbon also looks at the end-of-life emissions, namely the demolition of the building, transportation of materials to processing plants, material processing, and finally landfilling or recycling. This can be included as part of Scope 3 emissions, which is described in more detail in this article, but one main difference between these two principles is their focus. Emission scopes focus on a company and its processes while Embodied Carbon focuses on a product.

Embodied Carbon plays a vital part by allowing us to gain a better understanding of the bigger picture: the Whole Life Carbon of a product. This represents the sum of Embodied and Operational carbon, providing us with an overview of all the emissions over the whole life cycle, from material extraction, manufacturing, and use to the eventual disposal (or reuse). Embodied Carbon is especially important in construction, a sector which is responsible for nearly 40% of global energy related greenhouse gas emissions [2], and where Embodied Carbon is predicted to increase in share as operational emissions reduce over the coming years (mainly thanks to improving energy efficiency measures and grid decarbonisation). Without considering Embodied Carbon, we could find ourselves praising a “zero” emission building, covered in solar panels, and equipped with state-of-the-art energy management systems, only for it to be more polluting over its lifetime than would be a comparable building with less efficient systems and fewer solar panels – all because this crucial Embodied Carbon measure was overlooked.

 

The two faces: How does Embodied Carbon fit into the concept of Circularity? 

When applying circular design principles, the idea is to close the loop by identifying the output of one system and connecting it to the input of another. By doing so, waste is turned into value, and the use of virgin materials is bypassed. This inevitably cuts several steps in the value-chain, namely the carbon-intensive extraction of raw materials. This is even more consequential when looking at re-use instead of recycling, as all three first stages of a product’s lifecycle (material extraction, transportation to a manufacturing site, and the manufacturing of the product) are eliminated in that case. Given that these three stages are the largest contributors to Embodied Carbon, it is clear how circularity inevitably reduces carbon emissions. This is true of other core principles of Circular Design as well, whereby avoidance is always the preferred option, and the life of a product is extended as much as possible. Both principles reduce the carbon emissions generated by a product, either by minimising the amount of ‘new materials’ used to create a product, or by trying to extend the lifespan of an existing product.

 

Two birds, one carbon: 

From this perspective, Circularity can be understood as a “holistic” approach, allowing us to simultaneously address two very important issues: On one hand, we can reduce our contribution to global warming, while on the other, it allows us to reduce the use and waste of our planet’s finite materials.
The key concept at the heart of sustainable development can be defined as: “Our ability to meet the needs of the present without comprising the ability of future generations to meet their own needs” [3]. Relying on finite materials is most certainly unsustainable, and it is only right for the sake of future generations that we learn how to improve the re-use and recycling of such materials, as well as increase our use of regenerative, natural materials.

 

Following mother nature:

Nature is inherently circular, and so natural materials are an ideal element to include in any circular framework. From the growth of these natural materials to their eventual end-of-life, the loop is closed by nature itself, we need only be respectful of the nature’s default process. An example of going against this natural cycle is to dispose of biodegradable materials in landfills. This results in the decomposition of organic material into methane [4], a potent greenhouse gas, without any chance for the by-products of this decomposition to feed more life.

Another benefit of using bio-based materials, especially when one is mindful of these materials’ end-of-life, is carbon sequestration. Planting trees to offset carbon emissions has been scrutinised and criticised [5] in recent years, but if sequestered carbon was stored in a building, with a guaranteed storage of at least 60 years, and considerate end-of-life disposal, wouldn’t this be the favoured option? The source for these materials does not necessarily have to be trees either; fast-growing plants such as hemp have been effectively used as a building material to make brick and mortar, allowing for effective carbon capture and sequestration at a fast rate [6].

 

Closing the loop to make a point: 

This article has presented the reasons why Embodied Carbon is so important, why Circularity is one of our key tools to address this hidden side of carbon emissions, and why this approach teaches us so much about our world, our habits, and the sustainable way forward for design and innovation. The linear economy is, by definition, finite. We are free-falling through our planet’s reserves, and unless we learn to turn that line into a circle, we are doomed to hit the ground.

Here at Longevity Partners, we strive to help our clients consider circularity, whether that be through creating their Circular Economy Strategy, or helping them implement circular design principles in their new developments, subsequently reducing their Embodied Carbon. Click here, to find out more about Circular Economy and the services we provide.
If we’re going to hit the ground, let’s hit the ground running.

 

 

[1] Circular Economy Statement Guidance | GLA (london.gov.uk)

[2] How much carbon does the construction industry emit? | World Economic Forum (weforum.org)

[3] Sustainable Development (unesco.org)

[4] What is a landfill? Why are landfills bad for the environment? | Unisan UK

[5] The biggest problem with carbon offsetting is that it doesn’t really work | Greenpeace UK

[6] Hemp for Construction — UK Hemp Association

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