Microsoft commits to purchase low-carbon cement from Sublime Systems

Microsoft signed May 22 a binding agreement with Massachusetts-based Sublime Systems to purchase up to 622,500 mt of low-carbon cement over a six- to nine-year period.

The deal involves cement from Sublime's first commercial factory in Holyoke. The company uses a technology that avoids conventional carbon emissions in cement manufacturing, eliminating the need for carbon capture. This agreement is part of Microsoft's strategy to reduce construction emissions and access clean cement technology for its projects.

"In designing creative transactions such as this one with Sublime, Microsoft aims to accelerate the mass production and adoption of clean construction materials, enabling innovators to overcome the real, acute challenges of scaling in heavy industries with existing manufacturing capacity," said Jeff Leeper, vice president of Global Datacenter Construction at Microsoft.

"This purchase enables Microsoft to access Sublime's low-carbon cement technology regardless of where their construction is," said Sublime Systems CEO and cofounder Leah Ellis.

"This solves a previously intractable challenge for clean cement scale-up: the lack of long-term cement transactions contrasted with the immediate need for innovators to demonstrate bankable customers to fund their manufacturing. Microsoft is stepping up as the first customer for our future megaton-scale plant, enabling us to more rapidly build and scale Sublime Cement as a global, enduring solution for clean construction."

The contract includes a priority option for Microsoft to deploy Sublime Cement in its projects, with environmental attribute certificates available separately from the physical cement. This model is intended to address geographic and supply chain challenges in the cement industry.

Sublime Systems is developing its first commercial factory in Holyoke, supported by an $87 million award from the US Department of Energy. The company claims to produce an ASTM-compliant replacement in concrete for ordinary portland cement, which is made in kilns running at 1,450 C to decompose the feedstock limestone.

Earlier this week, Suffolk Technologies, the venture capital arm of builder Suffolk, announced an investment in Sublime Systems. It aims to accelerate Sublime's development of its electrochemical cement production process, which significantly reduces emissions and waste compared to traditional methods.

Suffolk Technologies has also prepurchased capacity from Sublime's upcoming commercial manufacturing plant.