Sucking CO2 Out of Thin Air Is No Longer Science Fiction
The Intergovernmental Panel on Climate Change has been clear: even aggressive emissions reductions will not be enough to limit warming to 1.5 degrees Celsius. Carbon dioxide removal, physically extracting CO2 from the atmosphere, is now considered a necessary complement to decarbonization. Direct air capture (DAC), the most technologically mature approach, uses chemical processes to filter CO2 from ambient air, concentrate it, and either store it underground or use it in industrial applications. In 2026, the DAC industry is scaling from demonstration to deployment, though enormous cost and energy challenges remain.
How Direct Air Capture Works
Two main approaches dominate the field. Climeworks, a Swiss company, uses solid sorbent filters: fans draw air over a material that chemically binds CO2. When the filter is saturated, it is heated to around 100 degrees Celsius, releasing pure CO2 for collection. Carbon Engineering, now owned by Occidental Petroleum, uses a liquid solvent process: air passes through a potassium hydroxide solution that absorbs CO2, which is then extracted through a series of chemical reactions at high temperatures. 24 New Species Discovered in the Deep Pacific: Exploring the Clarion-Clipperton Zone discusses the chemistry and engineering principles behind carbon capture. Both methods work; the question is whether they can work cheaply enough and at sufficient scale to matter.
The Mammoth Plant and What Comes Next
Climeworks’ Mammoth plant in Iceland, which began operations in 2024, captures 36,000 tonnes of CO2 per year, making it the world’s largest DAC facility. That sounds impressive until you realize global CO2 emissions exceed 40 billion tonnes annually. Mammoth removes roughly one-millionth of what humanity emits. To make a meaningful dent, the industry needs to scale by a factor of 100,000 or more. Climeworks plans a 10-fold larger plant for 2028. Carbon Engineering’s Stratos plant in Texas, under construction in partnership with Occidental, aims to capture 500,000 tonnes per year when it opens in 2026. The US Department of Energy has committed $3.5 billion to regional DAC hubs across the country.
Cost Is the Central Challenge
Current DAC costs range from $400-600 per tonne of CO2 removed. For context, a Canadian emits roughly 15 tonnes per year. At current prices, offsetting one person’s annual emissions through DAC would cost $6,000-9,000. The industry targets $100 per tonne by 2030-2035, which would bring costs in line with carbon prices in the EU Emissions Trading System and make DAC economically viable at scale. Getting there requires cheaper sorbent materials, waste heat integration, and massive economies of scale. Mariana Trench Deep Ocean Species: Exploring Life at Extreme Depths explores the broader economics of the energy transition. The learning curve for DAC mirrors early solar power: costs dropped 99% over four decades. Whether DAC can follow a similar trajectory is the trillion-dollar question.
Storage: Where Does the CO2 Go
Capturing CO2 is pointless if it escapes back into the atmosphere. Climeworks’ Iceland operations benefit from a unique geological advantage: captured CO2 is dissolved in water and injected into basalt rock formations, where it mineralizes into carbonate rock within two years, a process called CarbFix. This is permanent storage with negligible leakage risk. In Texas, Occidental plans to inject CO2 into depleted oil reservoirs, a proven technique from decades of enhanced oil recovery operations. Deep saline aquifers offer potentially unlimited storage capacity worldwide. The geology is generally well understood, but public acceptance of underground CO2 storage varies, and rigorous monitoring over decades will be essential to maintain trust.
DAC Is Not a Free Pass to Keep Emitting
The most important caveat about carbon removal: it supplements emissions cuts, it does not replace them. At any foreseeable scale, DAC will remove a small fraction of annual emissions. Fossil fuel companies that promote DAC as an alternative to reducing emissions are engaging in a well-documented delay strategy. The math is unambiguous: the cheapest tonne of carbon is the one never emitted. Efficiency improvements, electrification, and renewable energy deployment remain the primary tools for decarbonization. DAC addresses the residual emissions that cannot be eliminated through other means, and the historical CO2 already accumulated in the atmosphere. It is a necessary tool, but only one tool in a very large toolbox.
