Modernization Versus New Build Data Centers
What’s the real carbon cost?
With current global circumstances pointing to ever-growing demand for capacity, the industry must use every means possible to reduce its carbon emissions.
Modernization of data centers, which reuses existing buildings while expanding capacity, can deliver embodied carbon savings of 88% when compared with the material carbon cost of new projects.
Reusing this building eliminates the carbon emissions for a standard new construction building resulting in a modeled 88% embodied carbon emission reduction.
To analyze the carbon savings potential from the reuse of an existing facility, Serverfarm asked an independent consultant to calculate the carbon cost of using an existing data center compared with a new build of the same scale.
Consider an enterprise accessing 1MW of power through the construction of a new facility versus sourcing that same MW from a modernized pre-existing data center. This analysis found that when comparing embodied carbon savings, it would mean an extra four years of operation before an enterprise adds to its carbon footprint in the modernization case (accounting for both operational and embodied).
What is embodied carbon?
Embodied carbon is the CO2 emission associated with the manufacture, transport, construction, maintenance and end of life/disposal of a product or service.
To determine the embodied carbon cost of data centers, HKS, an international design firm, examined the operations of Serverfarm’s Chicago data center using a Whole Building Life-Cycle Analysis.
“Buildings and construction directly represent around 39% of all annual global greenhouse gas emissions. These emissions can be divided into two categories, building operations and building materials & construction. Each represents the operational carbon and the embodied carbon of buildings respectively,” says HKS.
HKS analyzed Serverfarm’s Chicago facility, a six-story building of just under 150,000 square feet with a capacity for housing more than 4,000 server cabinets. With a rack consumption of 61,320 kWh, the building consumes 25MW of power annually.
Were such a building to be constructed today using standard materials, the carbon cost, carbon dioxide equivalent or CO2e, would be 9,425,673kgs (use of low carbon materials would see a carbon cost of 8,301,691kg but add significantly to the financial cost).
The carbon costs were itemized by material including concrete, steel, glass, wood, plastics, composites, thermal and moisture protection, openings and glazing, and finishes. The factors analyzed by HKS covered potential for global warming, acidification, eutrophication, smog formation and cost of production in non-renewable energy.
The graph shows the embodied carbon for the same building in three different scenarios. The first one is a standard new construction, the second is a standard new construction with a low carbon concrete, and the third is reusing an existing building. These scenarios are broken down per material, showing how concrete is the main contributor of embodied carbon in this case.
Compare this to not constructing a new building but instead modernizing an existing building using epoxy coverings, gypsum boards and studs, and the embodied carbon cost drops to 1,151,439kg.
A modernized existing building avoiding a new construction project sees an 88% reduction in embodied carbon use largely associated with preserving the concrete structure of the building.
Carbon Savings for 1MW of power in a reused building
What can this tell us about the savings for an enterprise requiring 1MW of data center power per annum?
This calculation compares reuse of an existing building versus the construction of a brand-new facility at a utilization rate of 100%. While some buildings may achieve full capacity utilization, it is well known that uptime, redundancy and other operating parameters mean average utilization rates of around 50% are far closer to the average in the data center sector.
The Chicago data center has a total building operating carbon output of 144,044,154kg based on the operational carbon output per 7kW cabinet at 34,825kg for 4,136 cabinets.
In normal operations with the 88% reduction in embodied carbon, where 94% of carbon is produced from ongoing operations and 6% of carbon is embodied, this amounts to an equivalent of 238 server cabinets.
For an enterprise that needs to put into place 1MW of power per annum at 53% utilization (1.6MW annually capacity at 1.3PUE), using this existing data center can mean an enterprise gains 4 years of operation before it adds to its carbon footprint (accounting for both operational and embodied).
Reuse and modernization means carbon savings
The great strides made by the construction industry to address its carbon impact are welcome. Yet, all construction projects involve embodied carbon in the form of new raw materials such as concrete, steel and glass – and the building process itself.
In dealing with the immediate emergency, we must not lose sight of the long-term existential climate crisis.
It falls to end user enterprises requiring new capacity and those that provide such capacity to consider every potential carbon savings. Modernization versus new build means reduced greenhouse gas emissions now, which is our greatest urgency. If we consider mid-century as the timeframe, and acknowledge that we must resolve the climate crisis within, addressing embodied carbon is an essential component to mitigating this existential crisis. This strategy – building reuse – is immediately essential to address climate change.