Direct Air Capture: Can We Really Pull Carbon Out of Thin Air?

Direct Air Capture (DAC) is one of the most technical and futuristic carbon removal (CDR) strategies. At a high level, DAC works like a giant air filter pulling in ambient air, capturing CO₂, and converting it into concentrated forms that can be safely stored underground or used in products such as concrete and building materials.

Can DAC Scale? Understanding the Technology Behind the Promise

The biggest unanswered question around DAC is not whether it works (it does), but whether it can scale affordably, sustainably, and fast enough to matter. To understand the challenge, it’s useful to look at how DAC systems operate. There are two primary types:

Active DAC Systems: These use large fans to push air across chemical sorbents that absorb CO₂. 

• Benefit: faster capture 

• Challenge: extremely energy-intensive

Passive DAC Systems: These rely on natural wind flow over sorbents. 

• Benefit: lower energy needs 

• Challenge: slower capture, harder to reach high volumes

Both approaches require significant heat to release the CO₂ from the sorbent during regeneration, allowing the sorbent to be reused. This heat requirement is one of the most expensive and carbon-intensive parts of the process.

Some companies have addressed this by colocating DAC facilities near geothermal resources, harnessing renewable heat from the earth. This dramatically improves the net carbon removal efficiency.

Other barriers include:

• Cost and durability of sorbents, which determine long-term operating expenses

• Energy sources, as fossil-powered DAC plants risk emitting more CO₂ than they remove

• Gigaton-scale infrastructure, which would require massive global build-out

Even with these challenges, DAC plays a unique role in the climate solution toolkit, especially for hard-to-decarbonize sectors such as shipping, travel, or oil and gas. Utilizing DAC as a solution to offset these industry emissions through carbon capture is critical for future carbon accounting strategies. 

Additionally, because DAC pulls CO₂ from the ambient atmosphere rather than land-based baselines, the carbon accounting is extremely transparent and straightforward. This makes DAC one of the most credible and verifiable forms of carbon removal available today.

Where Science, Policy & Community Intersect

Despite rapid technological progress, the enabling environment for DAC still lags behind.

Policy Support

Governments can accelerate DAC by:

• Offering subsidies or tax incentives for facilities powered by renewable or waste heat

• Strengthening carbon reduction policies like cap-and-trade

• Setting clear global accounting rules for high-quality carbon credits

Community Support

Scaling DAC will create new long-term jobs, particularly in regions transitioning away from fossil fuel extraction. But community buy-in is essential for siting facilities, especially since DAC plants operate for decades. Trust-building, transparent communication, and local workforce training will influence whether communities embrace or resist this new climate infrastructure.

Bottom Line: DAC’s Future Depends on More than Technology

Direct Air Capture has the potential to remove historic emissions, support hard-to-decarbonize sectors, and provide high-integrity carbon storage. But for DAC to fulfill its promise, we must align technology, policy, and community readiness.

For DAC to reach its potential, we need:

• Low-carbon energy sources to power large-scale capture

• Internationally consistent carbon markets that reward verified removals

• A skilled local workforce to operate facilities and sustain regional economies

With the right enabling conditions, DAC can become a backbone of global carbon removal, not replacing nature-based solutions, but strengthening the entire climate portfolio. 

The information shared in this post came from the resources shared during the AirMiners BootUp program. If you’re interested in diving deeper into DAC as a carbon removal pathway, you should think about joining their free introductory CDR cohort. 

Glossary 

• Compliance Market — A regulated carbon market where governments require companies to reduce emissions or buy certified carbon credits to meet legal limits.

• Byproduct — A secondary material or substance produced during a process. In DAC, this could be concentrated CO₂, heat, or carbonate solids.

• Additionality — The principle that a carbon removal project must store more CO₂ than would have occurred without the project. If the activity would have happened anyway, it is not additional.

• Mineralization — A process where CO₂ chemically reacts with minerals to form stable, solid carbonates. Often used for permanent carbon storage.

• Sorbent — A material used to capture CO₂ from air. Sorbents can be solid (like resins) or liquid (like alkaline solutions).

• Cap-and-Trade — A policy where governments set a limit (“cap”) on emissions and allow companies to trade emission permits. Firms that reduce emissions can sell their excess allowances.