Microsoft has announced a new partnership with a Canadian startup to remove 300,000 tonnes of carbon dioxide. Microsoft’s 10-year deal with Arca Climate Technologies will see the Corporation purchase almost 300,000 tonnes of permanent carbon removal credits, marking a major milestone in scaling permanent carbon removal through mineralisation.
Arca Climate Technologies provides carbon dioxide removal (CDR) by repurposing mine tailings (waste rock) and other industrial waste. The company harnesses mineralisation to remove carbon dioxide from the atmosphere, leveraging existing industrial infrastructure and repurposing alkaline waste streams to capture and permanently store atmospheric CO2 as stable carbonate minerals. The approach offers a low-cost and permanent means to store carbon within existing industrial sites.
Further, Arca utilises autonomous robots to continuously monitor and verify the rate and volume of carbon capture. The company’s measuring and reporting technologies support third-party verification and having a real-time picture of CO2 flux enables it to remotely direct the rovers’ Smart Churning counterparts for maximum efficiency. This means that Microsoft will be provided with the credits and verified proof of carbon removal, helping to offset the tech giant’s rising emissions from AI and data centre operations.
Arca rover performing Smart Churning activities on mine waste
Research by Arca has identified 21 gigatonnes of carbon removal capacity in suitable historical mine waste material, plus gigatonnes more in other streams of alkaline industrial waste. For context, the world emitted 37.8 gigatonnes of CO2 in 2023 alone.
“We have a unique opportunity to utilize one form of waste (mine tailings) to neutralize another (excess atmospheric CO2). The result is less waste and a healthier environment”, commented Paul Needham, Arca CEO. “This agreement with Microsoft validates Industrial Mineralization as a viable pathway for durable carbon removal with the potential to scale and meaningfully contribute to global climate goals”[i].
Phil Goodman, Director of Microsoft’s Carbon Dioxide Removal Program, has said: “This offtake agreement diversifies Microsoft’s carbon removal portfolio into a pathway that combines scalability and permanence. Arca brings notable scientific expertise and has proven they can sequester carbon through their demonstration project, giving us confidence to enter into a multi-year agreement.”[ii]
Microsoft continues drive for carbon negativity by 2030
The deal with Arca is part of a wider push by Microsoft towards carbon removal as the corporation targets becoming carbon negative by 2030 and erasing all historic emissions by 2050.
“By 2030 Microsoft will be carbon negative, and by 2050 Microsoft will remove from the environment all the carbon the company has emitted either directly or by electrical consumption since it was founded in 1975.”[iii]
With expanding data centre, artificial intelligence and supply-chain operations, tech giants are faced with a mounting and pressing challenge in how to address their emissions. As of early 2025 Microsoft was the biggest purchaser of carbon credits, accounting for 63% of total CDR purchase volume in 2024. The corporation secured around 5.1 million metric tonnes of CDR credits[iv], it dwarfs second-placed Google which secured just over 500,000 tonnes. Microsoft now has a range of investments in carbon removal technologies, including direct air capture (such as Canada’s Deep Sky), as well as major biomass sequestering projects in the U.S. and Europe.
[i] Arca-Press-Release-MSFT-offtake-29-October-2025.pdf
[ii] Ibid
[iii] Microsoft will be carbon negative by 2030 - The Official Microsoft Blog
[iv] What Is Carbon Dioxide Removal? Top Buyers and Sellers of CDR Credits in 2024
Lauren has extensive experience as an analyst and market researcher in the digital technology and travel sectors. She has a background in researching and forecasting emerging technologies, with a particular passion for the Videogames and eSports industries. She joined the Critical Information Group as Head of Reports and Market Research at GRC World Forums, and leads the content and data research team at the Zero Carbon Academy. “What drew me to the academy is the opportunity to add content and commentary around sustainability across a wealth of industries and sectors.”
