Microsoft funding new approach for carbon removal

Microsoft agreed to fund a carbon capture technology that uses the natural properties of limestone to take carbon dioxide out of the atmosphere, the startup firm Heirloom Carbon announced Thursday.

The tech giant will purchase about $200 million worth of carbon credits — equivalent to 315,000 tons of carbon — over 10 years from Heirloom to fund its carbon capture operations in Louisiana and elsewhere in the U.S. 

Heirloom’s direct air capture process uses processed limestone to draw carbon dioxide out of the air, where it is then removed from the stone and stored underground or in concrete.

“Microsoft’s agreement with Heirloom is another important step in helping build the market for high-quality carbon removal and supports our path to become carbon negative by 2030,” Microsoft Senior Director of Energy and Carbon Brian Marrs said in a statement. 

“As an investor in and customer of Heirloom, we believe that Heirloom’s technical approach and plan are designed for rapid iteration to help drive down the cost of large-scale Direct Air Capture at the urgent pace needed to meet the goals of the Paris Agreement,” he continued.

In addition to a pledge to go carbon-negative by 2030, the company has also committed to paying back all carbon the company has ever produced by 2050. 

Heirloom’s Louisiana facility was selected to receive up to $600 million from the Department of Energy last month, funding provided by the Bipartisan Infrastructure Law passed under the Biden administration. 

Energy Secretary Jennifer Granholm described the technology as “giant vacuums that can suck decades of old carbon pollution straight out of the sky.” The Heirloom project in Louisiana and a second project in south Texas were selected for federal funds.

Heirloom leadership said Microsoft’s funding is critical to finance future direct air capture facilities and continue the company’s goals.