This is the latest in a series of guest columns by Nancy Novak discussing important issues related to the sustainability of data centre construction. This column discusses an approach for decarbonizing the most significant material used in data centre construction.
It is not new news that buildings use a lot of concrete. There is no substitute for it, and it is emissions-intensive to produce. What is new is technology for manufacturing concrete that not only lowers cement volume but captures and sequesters CO2. As data centre developers continue to evolve designs to minimise the impact to the environment, carbon capture in concrete production represents a significant opportunity to minimize the carbon footprint.
For years, the data centre industry has focused on operations as a means to reduce carbon emissions through things like higher energy efficiency. From a construction standpoint, though, solutions to reduce the carbon intensity of buildings have been limited. Using materials like recycled steel had an impact, but data centres are highly concrete-intensive structures. Greener concrete would have a much larger impact, which is what led Compass Datacenters to CarbonCure.
Using CarbonCure technology, concrete captures carbon waste and injects it into concrete, sequestering it permanently. Injecting carbon in mineral form not only improves the compression strength of the concrete, but also reduces the volume required per project. Most importantly, it permanently eliminates the captured CO2 from the atmosphere, driving substantial positive change in the impact of concrete production on the environment. All of those factors make this approach to concrete production a significant step toward lowering the carbon footprint of data centres.
Search for a solution
To date, the tech industry has not been a primary target of environmental activism and change. Most climate change discussions focus on limiting emissions from the automotive, aviation and energy sectors. But the industry is mindful of its impact and proactively searching for ways to do better.
It is a well-publicised fact that data centres are energy intensive. According to research firm IDC, the data centre industry has the fastest-growing carbon footprint within the IT sector, with the amount of energy used by data centres doubling every four years. The number of data centres worldwide has grown from 500,000 in 2012 to more than eight million today, and expansion will continue on that trajectory as more people work remotely and stream entertainment from home in the wake of the pandemic. A lot of that expansion will be new construction.
Engineering firm Thornton Tomasetti conducted a multi-year study on embodied carbon. In it, Tomasetti recognises that data centres and hospitals – mission critical structures, have the overall highest levels of embodied carbon of any asset category. In consultation with Thornton Tomasetti, Compass discovered how effective CarbonCure technology could be in reducing the carbon footprint of each of its new campuses. Building sizes vary, but estimates showed that using CarbonCure has the potential to reduce the CO2 footprint of each Compass campus by around 1,800 tons, equivalent to CO2 sequestered by 2,100 acres of forest or driving a car 4 million miles.
Having quantified CarbonCure’s potential, as it relates to Compass Datacenters specifically, and with tested confidence in the integrity and application of the product for Compass’s model, the next step was to ensure Compass’s supply chain was able to meet the need for CarbonCure-manufactured cement across the globe. RFP respondents were widely familiar with the product, and eager to support this new, better way to build.
Compass Datacenters’ customers can now start their projects from a more positive carbon position. As it seeks to continue eliminating carbon in new builds, Compass is now investigating opportunities to use aggregate with captured CO2 in place of natural limestone rock mined from quarries.
The Structural Engineers 2050 Commitment challenges structural engineers to take ownership and a more active role in reducing embodied carbon emissions in the built environment and Compass believes carbon capture in cement is an important, if not the most important, way to achieve those goals. Compass began constructing new centres with CarbonCure technology in 2020. It is an exciting new frontier and opportunity for the engineering and construction industry to deliver more environmentally responsible projects.