Microsoft Contracts with Sublime Systems for Low-Carbon Cement

Building with low-carbon materials

In Northern Virginia, we recently built our first datacenters made from a hybrid of cross-laminated timber, steel, and concrete. Together, concrete and steel account for approximately 13% of global CO₂ emissions. By introducing cross-laminated timber into the mix, we’re able to reduce the embodied carbon footprint of these two new datacenters by an estimated 35% compared to conventional steel construction and 65% compared to typical precast concrete.

Fortunately, there’s been a growing demand for cross-laminated timber over the past decade, particularly in the United States and Europe, which enabled us to secure enough material to build our Northern Virginia datacenter. But that’s not always the case—we often see gaps in markets for innovative and low-carbon solutions that we’re relying on to meet our carbon negative goal. One strategy we use when low-carbon building materials aren’t available is purchasing EACs.

Buying environmental attribute certificates

For example, let’s say we’re planning to build a new datacenter in Washington when we find a low-carbon cement solution in Florida. Rather than shipping this cement across the country, incurring both monetary costs and carbon emissions, we can use traditional cement purchased locally while obtaining an EAC from Florida. That low-carbon cement is still sold, and likely at a cost more competitive with traditional cement.

While EACs have been used for years for other products like electricity and sustainable aviation fuels, their use for building materials is relatively new. Given the nascency of the EAC market for low-carbon building materials, Microsoft collaborated with Carbon Direct to publish ”Criteria for High-Quality Environmental Attribute Certificates in the Concrete and Steel Sector.” Microsoft will use the criteria to guide our high-quality EAC purchases, accelerating decarbonization and catalyzing market expansion for decarbonized materials across supply chains. The criteria cover seven key areas: qualifying conditions, social harms and benefits, environmental harms and benefits, additionality and baselines, catalytic impact, verifiability, and leakage.

Additionally, Microsoft has joined RMI (formerly known as the Rocky Mountain Institute) and the Center for Green Market Activation’s cement and concrete Working Group in developing a book and claim system—which provides a chain of custody model that allows environmental attributes to be decoupled from the physical product—in partnership with other leaders in cement and concrete technologies.

Buying EACs over several years signals demand in a sector that often operates on an as-needed basis. Demonstrating that customers are willing to pay  for the environmental attributes can help unlock the capital necessary to build plants that will operate for decades, helping to reduce carbon in the sector and build markets.

While EACs are an important strategy for us today, we see them as a temporary strategy for catalyzing construction of new low-carbon building material manufacturing facilities. Our first priority is to buy and use low-carbon materials. The third prong of our strategy to build new markets is investing to signal market demand.

Investing to signal market demand

Through our $1 billion Climate Innovation Fund (CIF), we accelerate the development and deployment of first-of-their-kind technologies, helping introduce and hopefully scale companies’ innovative solutions into the market. We’ve used this market-building approach to accelerate progress in sectors like carbon dioxide removal, advanced energy systems, building materials, and sustainable fuels.