Direct air capture (DAC) of carbon dioxide is today a hotly debated carbon management technology, attracting scepticism in some quarters but also growing investment reflecting its crucial role in the maths of delivering Net Zero.
Some firms in the space are focused on large-scale DAC projects with permanent carbon sequestration in mind, while others, like Netherlands-based Skytree or Aircapture in the US, are developing smaller, modular DAC systems designed to integrate directly into industrial CO2 supply chains and deliver CO2 for either utilisation or large scale storage.
Could this modular model make scaling DAC fast more viable, if costs continue to fall?
The economics of DAC
The economics that attach to DAC have long been a focus. Large-scale projects, such as those developed by Swiss carbon removal technology specialist Climeworks and Canada-based clean tech firm Carbon Engineering, have so far relied heavily on government funding and voluntary carbon credit markets to be viable.
While these firms aim to drive down costs over time through scaling and tech and learning advances, the current price of DAC-derived CO2 is still high.
Public estimates made by leading DAC projects suggest costs well above $500 per tonne of CO2 for many, which is far more expensive than commercial merchant CO2 prices.
But the wider point is that gaseous waste management needs a large-scale solution. Waste per capita keeps rising, and gaseous emissions, particularly CO2, are easily the largest share. Data shows that more CO2 waste by mass has been released into the atmosphere than solid and liquid waste combined. It is a stark truth that highlights both the urgency of DAC and the scale of the challenge. In short, the numbers need to be made to add up.
Skytree has argued that its approach is ahead of the pack in delivering faster cost reductions through modularity and cost benefits from mass manufacturing through many near term deployments. Further reductions are possible by utilising available onsite waste heat from industry, geothermal or data centers. According to Rob van Straten, CEO of Skytree, the company’s iterative, fail-fast mentality also drives down cost.
“We are on our 14th technology iteration already” he says. “That is because we deploy machines, collect performance data, and improve each generation rapidly. We do not have to wait years to see what works.”
Modular DAC still faces questions, since energy remains a key expense and all DAC techs , require significant power to run. Without access to low-cost renewable energy, DAC-derived CO2 will struggle to compete with existing industrial CO2 sources – but there is lots of competition for renewables.
For van Straten, it is clear cost reductions can be delivered through economies of scale in manufacturing, but it is not a position that all share.
Skytree, all the same, says it is on the way to significant cost reductions. If $100 has long been the target, what might stand in the way of getting there?
Material constraints – Many DAC systems use sorbents that degrade over time, requiring costly replacement.
Energy intensity – DAC is energy-intensive. If powered by fossil fuels, that negates the climate benefits, but to be powered by renewables it must compete and win out against other industries for that energy supply.
Infrastructure limitations – Transporting and storing captured CO2 remains a challenge and a cost.
The company sees near-term applications in greenhouses and food and beverage production, where DAC could provide an alternative CO2 source as fossil-based supplies decline. The Netherlands, where Skytree is based, is already seeing a shift, with CO2 suppliers like Shell and Yara redirecting captured emissions toward permanent sequestration instead of selling it to industry.
“If CO2 from point-source capture is redirected to permanent storage, industrial users will need alternative sources. DAC could play a role here,” van Straten said. “We are working on solutions that deliver CO2 reliably at stable prices without requiring an entirely new infrastructure.”
What next? Key questions for the summit
With the gasworld European CO2 Summit 2025 around the corner, the discussion around DAC is shifting, while key questions remain:
How fast can modular DAC reduce costs to compete with existing CO2 sources?
What are the realistic timelines for making DAC an economically viable for industrial CO2 supply?
What policy mechanisms, beyond subsidies, could support DAC adoption in the short term?
Are there specific industrial applications now where DAC already stacks up financially?
