This article is co-written by Ed Ansett of i3 Solutions. Both authors are members of of the i3 Solutions EYPMCF GHG Abatement Group.
Embodied carbon costs are mostly accrued at the construction stage of any project. However, such costs go further than simply the carbon price of concrete and steel manufacture and use. How best then to identify, consider and evaluate the real embodied carbon cost of infrastructure-dense and energy-intensive buildings such as a data center?
According to the United Nations Environment Programme (UNEP) the carbon cost of building is rising. The UNEP Global Alliance for Buildings and Construction (GlobalABC) global status report highlighted two trends. It says: “CO2 emissions from the building sector are the highest ever recorded” and “new GlobalABC tracker finds sector is losing momentum toward decarbonization.”
The simple fact seems to be that emissions from embodied carbon in construction are getting further away from, and not closer to net zero.
A fixed carbon cost?
But while it is obvious that not all buildings are the same in embodied carbon terms, in almost all cases these emissions are mostly created at the beginning of the building lifecycle and cannot be reduced over time. This is often and, in some cases, especially true in data centers.
When focusing on the data center as a building – say a new build 50MW facility - it is clear that in order to meet its design objective, it will require more power and cooling infrastructure equipment when compared with other forms of commercial real estate such as offices, warehousing and retail spaces.
For data centers, embodied carbon includes all emissions not attributed to operations and the use of energy and water in its day to day running. This includes emissions associated with resource extraction, manufacturing, and transportation, as well as those emissions during the installation of materials and components used to create the built environment. It also includes lifecycle emissions from their ongoing use including maintenance, repair and replacements as well as the end-of-life activities of deconstruction, transportation, waste processing and disposal. These lifecycle emissions must be considered to account for the total embodied carbon cost.
The complexity of mission critical facilities makes it more important than ever to have a comprehensive process to consider and address all sources of embodied carbon emissions early in design and equipment procurement. Only by early and detailed assessment can operators inform best actions which can contribute to immediate embodied carbon reductions.
Embodied Carbon + Operational Carbon = Whole Life Carbon
Boundaries to measure the embodied carbon and emissions of a building at different points in the construction and operating lifecycle are Cradle to Gate; Cradle to Site; Cradle to Use and Cradle to Grave carbon calculations, where “Cradle” is referenced as the earth or ground from which raw materials are extracted.
For data centers these higher levels of infrastructure are equipment-related, additional, and important considerations. In embodied carbon terms they will be categorized under Scope 3 of the GHG Protocol Standards - also referred to as Value-Chain emissions.
Much of the Scope 3 emissions will be produced by upstream activities that include and cover materials for construction. However, especially important for data centers is that they also include the carbon cost for ongoing maintenance and replacement of the facility plant and equipment.
That brings us to whole of life calculations which will combine embodied and operational carbon.
Combining embodied and operational emissions to analyse the entire lifecycle of a building throughout its useful life and beyond is the Whole Life Carbon approach. It ensures that the embodied carbon (CO2e emissions) together with embodied carbon of materials, components and construction activities are calculated and available to allow comparisons between different design and construction approaches.
Sustainability is much more than operating efficiency
The great efforts to improve efficiency and reduce energy use – as measured through improvements in PUE – have slowed operational carbon emissions even as demand and the scale of facilities has surged. But reducing operational energy of the facility is measured over time and such reductions are not accounted for until 5, 10, 30 years into the future.
However, embodied carbon is mostly spent up-front as the building is constructed; there is, therefore a compelling reason to include embodied carbon within all analyses and data center design decisions. A ‘Whole Life’ carbon approach that considers the Embodied and the Operational emissions, provides the opportunity to contribute positively to global goals to reduce emissions of greenhouse gases – and will save financial costs.
For more guidance on the subject, the i3 Solutions Group and EYP MCF GHG Abatement Group has recently published Embodied carbon considerations for Data Centers, Scope, Impact, Reductions.
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