The world's largest direct air capture plant is now ramping up operations in Ector County, Texas. STRATOS, operated by 1PointFive, a subsidiary of oil company Occidental, is designed to remove 500,000 tonnes of CO2 per year from the atmosphere at full capacity. That is roughly equivalent to the annual emissions of 100,000 average Americans, and represents the first demonstration that industrial CO2 removal at this scale is technically possible.
How the Plant Pulls CO2 From the Air
In direct air capture (DAC), outdoor air is drawn by fans into contact with a chemical solution that selectively binds CO2. STRATOS uses a liquid-based technology developed by Carbon Engineering: an aqueous potassium hydroxide solution reacts with CO2 from the air to form potassium carbonate. Through subsequent heating (calcination), the CO2 is concentrated and separated. It is then compressed and injected into deep saline aquifers beneath the Texas surface, where it remains permanently stored.
The process is energy-intensive. 1PointFive states that STRATOS will be powered by renewable electricity to avoid undermining the plant's carbon balance with its own emissions. Critics point out that the Texas grid still relies heavily on fossil fuels, making the actual net balance of the plant difficult to verify independently.
In Comparison: What Other Facilities Achieve
Until now, Iceland's Mammoth plant by Climeworks was the world's largest DAC facility. Mammoth, which began operating in 2024, captures around 36,000 tonnes of CO2 per year according to the manufacturer. STRATOS is designed for 500,000 tonnes at full capacity, fourteen times as much. Global DAC capacity before STRATOS stood at around 57,000 tonnes per year; with STRATOS, it rises above 550,000 tonnes.
To put these numbers in perspective: humanity emits around 37 billion tonnes of CO2 per year according to IPCC estimates. Five hundred thousand tonnes amounts to roughly 0.0014 percent of that total. The International Energy Agency has calculated that in a net-zero scenario by 2050, around one billion tonnes of CO2 would need to be mechanically removed from the atmosphere each year. STRATOS is a meaningful proof of technical feasibility, not yet a game-changer for the global climate.
What distinguishes STRATOS from earlier plants is its modular design with several parallel production units, enabling step-by-step scaling, and the first-ever demonstration of economic operability under real industrial conditions at this scale.
Microsoft as Buyer, Occidental as Operator
The largest single buyer of STRATOS carbon removal credits is Microsoft. The company has contractually committed to purchasing 500,000 tonnes of CO2 removal, which 1PointFive describes as the largest single DAC purchase agreement to date. Microsoft has set a target of becoming carbon negative by 2030 and offsetting all historical emissions since the company's founding in 1975 by 2050.
That an oil company operates the world's largest climate remediation plant raises questions. Occidental produces around 1.2 million barrels of oil per day; the CO2 emissions from burning that volume far exceed STRATOS's annual capacity. The plant is also a business model for Occidental: carbon removal credits trade at between 400 and 1,000 US dollars per tonne. At full utilization, STRATOS could generate up to half a billion dollars in annual revenue.
Scale and the Road to Cost Parity
STRATOS began its phased ramp-up in early 2026, with full operating capacity targeted for later in the year. Construction costs are reported at around one billion US dollars, equivalent to 2,000 dollars per tonne of annual capacity.
The industry expects these costs to fall sharply through economies of scale over coming decades, similar to the trajectory of solar energy: a solar module cost around 100 dollars per watt in 1976 and now trades below 0.30 dollars. If a similar learning curve applies to DAC, carbon removal could become economically competitive with other climate measures within a few decades. STRATOS is the first real evidence that this path is at least industrially walkable.