Microsoft announced a new agreement for the removal of up to 350,000 tonnes of CO2 from the atmosphere over ten years with marine carbon dioxide removal (mCDR) provider Ebb Carbon.

Founded in 2021 by former Tesla, SolarCity, and Google X executives, Ebb Carbon provides a solution aimed at enhancing the natural ability of the ocean to store CO2, while improving ocean health by reducing ocean acidification. The company’s utilizes an Electrochemical Ocean Alkalinity Enhancement (OAE) approach to ocean-based carbon removal that accelerates the natural ocean alkalinization process, by separating seawater into acidic and alkaline streams, with the alkaline stream returned to the ocean, where it mimics natural alkalization, converting CO2 in seawater into bicarbonate ions and enabling the ocean to absorb additional CO2 from the atmosphere. By countering rising ocean acidification resulting from climate change, the solution can also help to addresses threat to marine life and coastal ecosystems.

Ben Tarbell, CEO of Ebb Carbon, said:

“Microsoft is setting a powerful example with its commitment to becoming carbon negative by 2030 and by using its purchasing power to accelerate the most promising climate solutions. This agreement underscores the potential of Ebb Carbon’s technology to contribute meaningfully to gigaton-scale carbon removal in the years ahead.”

Under the new agreement, Ebb Carbon will initially deliver 1,333 tonnes of carbon removal, with the option for Microsoft to purchase up to 350,000 tonnes over ten years. The agreement marks the latest in a rapidly growing series of carbon removal deals for Microsoft, forming part of the tech giant’s initiative to become carbon negative by 2030, which span an increasing range of solutions and technologies, including an ocean-based deal last year with Running Tide, as well as direct air capture (DAC), ocean-based carbon removal, and biochar-based projects, and several large-scale nature-based and BECCS-based carbon removal deals.

Brian Marrs, Senior Director of Energy & Carbon Removal at Microsoft, said:

“The ocean is a critical part of the carbon cycle. Ebb has developed technology to leverage the natural attributes of the ocean – its massive surface area and natural ocean processes that already pull CO2 from the atmosphere – to durably remove and store large volumes of atmospheric carbon. We are pleased to collaborate with Ebb to both accelerate the scientific foundation for ocean-based carbon dioxide removal and explore the potential of ocean-based carbon removal solutions at scale.”

CO2 removed through the new agreement will be measured reported and verified by Ebb using a recently-released OAE protocol by carbon removal standard and registry provider Isometric, ensuring that the credits delivered meet high standards of scientific rigor and transparency.

Stacy Kauk, P.Eng., Chief Science Officer at Isometric, said:

“OAE is promising because of the vast surface area of the ocean. This same fact requires careful monitoring, reporting and verification (MRV). Isometric’s protocol requires measurements and the use of internationally recognized ocean models to quantify carbon removal so buyers and suppliers can be sure one credit equals one tonne of carbon dioxide removed from the atmosphere. This is another step towards creating trust and transparency in carbon markets.”