05 MAR, 2024
EMBODIED CARBON, OPERATIONAL CARBON
& ZERO NET CARBON BUILDINGS
‘To achieve a zero net carbon building, you must generate and execute a comprehensive plan that may incorporate various strategies to eliminate the embodied and operational carbon of your construction project’ said Jessica, your Building Sustainability Consultant.
Okay, and now what do you do?
Well, let’s take a step back for a minute – before we know the solution, we must understand what is the problem. In this case, before we know the ‘how’ of constructing a zero net carbon building, we must understand the ‘what’ that is preventing any regular building from being carbon net-zero. Our Building Sustainability Consultant, Jessica, has already pointed out a part of the answer to this question. In a nutshell, a non-carbon-net-zero building would be constructed and operated with a carbon footprint that exceeds the capacity of which it reduces. This carbon footprint can be calculated as the total of the building’s embodied carbon and operational carbon. With that being said, it would be necessary for us to understand what embodied and operational carbons are in order to solve our problem. Thus, if you are unfamiliar with these two terms (or if you’d like a little review), then allow me to explain their fundamental concepts to you:
Embodied Carbon
Embodied carbon (sometimes also referred to as upfront carbon) refers to the greenhouse gas (GHG) emissions arising from the manufacturing, transportation, installation, maintenance and disposal, of a product or a system. A building or construction’s embodied carbon is measured before its operation and refers to the total embodied carbon of its building materials. It is measured by scientists using a method called life cycle assessment (LCA) to track the emission produced over the full cycle of a product or process. These emissions are converted into metrics that reflect their potential effects on the environment. A common metric is global warming potential (GWP), which is quantified in kilograms of CO2 equivalent (kgCO2e).
Operational Carbon
Operational carbon, in contrast with embodied carbon, refers to the GHG emissions due to a building or construction product’s energy consumption during operation and is measured after a building or construction product starts its operation. These energy consumptions may due to air conditioning and other functions of the HVAC system, water heating, lighting, elevator/lift operation, and electronic equipments (plug loads). Operational carbon is typically measured in tonnes of CO2 equivalent per year (MT CO2e./yr).
Now, having had some understanding about embodied and operational carbons of a construction project, we may begin to look into how to handle them in building a zero net carbon building. A zero net carbon building is defined as a building whose carbon emission during its construction and operation is equal to the amount of emission that it removes from the atmosphere via various emission removal measures. It requires thorough planning from its construction process through its final operation strategies. Ideally, the planning objective for a zero net carbon building project shall focus on minimising the building’s embodied carbons in order to reduce the efforts and expenses that may be required to offset it once the building is completed and begins to operate with unpredictable variables, such as different occupancies and user needs. However, it is inevitable that different projects with different existing social, environmental and economical context will require different strategies to achieve zero net carbon requirements. In cases where a project’s capability to minimise its embodied carbon is limited, more efforts and/or expenses shall be spent on carbon offsetting through environmental-friendly operation methods and infrastructures.
Is a zero net carbon building, then, worth it? You may wonder…
The simple answer is probably yes. Like trying to eliminate your personal carbon footprint through consciously pursuing low-carbon products and lifestyles, choosing to build, live, or work in a zero net carbon building is also a conscious action that we can do to demand for a carbon neutral world. In addition, even though, it is the responsibility of all industries to eliminate the embodied carbon of their products, the embodied carbon of construction projects has been identified as a significant contributor to the global GHG emissions and therefore requires urgent action to address it. Thankfully, with increasing demand for sustainable solutions in the building and development industry nowadays due to either public or private agenda, various associating industries, such as those in raw material resourcing and energy sectors, are urged to become more in-tuned with local and global sustainability visions in order to maintain their competence against advancing and emerging competitors. With that, building professionals, consultants and/or project owners are given the power to determine how a sustainable environment shall be built for our future selves as well as the next generations.
Do you believe that a carbon neutral world is possible in the near future? If the world must be carbon neutral or even carbon negative asap, what should we do and improve at this very moment? Share your ideas in the comment section below and let us know!
Sincerely,
J.