How much CO2 can direct air capture remove today?

As of 2023, global DAC facilities collectively capture less than 20,000 tons of CO2 per year—orders of magnitude below the gigaton-scale needed for climate impact.

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Direct Air Capture: Weighing the Pros and Cons

Exploring the benefits and challenges of direct air capture technology for carbon removal and climate solutions.

By Medha deb

Created on Sep 27, 2025

Exploring the benefits and challenges of direct air capture technology for carbon removal and climate solutions.

Direct Air Capture: Understanding the Technology Behind Carbon Removal

Direct air capture (DAC) is a rapidly evolving climate technology designed to remove carbon dioxide (CO₂) directly from the ambient air. Its promise lies in helping the world progress toward net-zero emissions by extracting legacy CO₂ already contributing to global warming. As the urgency for climate solutions becomes clearer, DAC’s potential—as well as its limitations—are coming into sharper focus.

What Is Direct Air Capture?

Direct air capture is a suite of engineered processes that chemically or physically separates CO₂ from the atmosphere. Air is forced through a contactor containing either a liquid solvent or a solid sorbent that reacts with or binds to the CO₂. Once captured, the CO₂ can be compressed and either permanently stored underground in geological formations or reused in products such as fuels, building materials, or carbonated beverages.

Liquid solvent systems use chemicals (often alkaline solutions) to absorb CO₂ as the air passes through them.
Solid sorbent systems rely on filter-like materials that chemically bind CO₂.

After absorption, external power—commonly heat, electricity, or pressure—separates (“regenerates”) the CO₂ from the solvent or sorbent, creating a concentrated CO₂ stream for storage or utilization.

How Direct Air Capture Works

The process of DAC involves several critical stages that determine its effectiveness and environmental impact.

Air Intake: Large fans draw enormous volumes of atmospheric air into the capture system.
CO₂ Capture: The air is exposed to solvents or sorbents within the system’s chambers, selectively removing CO₂ molecules from the incoming air stream.
Regeneration: The CO₂-laden medium is processed—usually heated—to release pure CO₂. This purified CO₂ is then collected.
Compression and Storage or Utilization: The extracted gas is compressed for pipeline transport and injected deep underground for long-term storage, or—less commonly—used in the production of goods.

Why Direct Air Capture Matters

While reducing emissions from industry, energy, and transportation is essential, those actions alone are insufficient to stabilize the climate. Many climate models indicate that, even with aggressive emissions cuts, it will be necessary to remove gigatons of CO₂ from the air to stay below critical warming thresholds. DAC represents a scalable and technology-driven pathway to achieving negative emissions. Unlike point-source carbon capture, which sequesters emissions from specific sites like power plants, DAC can counteract legacy or “diffuse” emissions that have dispersed globally over the past century.

Types of Direct Air Capture Technologies

Leading DAC systems fall into two main categories, each with unique characteristics and challenges:

Technology Type	Description	Sample Companies	Main Inputs
Liquid Solvent Systems	Passes air through a liquid (often alkaline solution) that binds to CO₂	Carbon Engineering (Canada)	Heat, water, electricity
Solid Sorbent Systems	Uses solid filters or resins to capture CO₂	Climeworks (Switzerland), Global Thermostat (USA)	Heat, electricity

Novel variations continue to be developed, including electrochemical DAC approaches that could further reduce energy costs by relying mostly or entirely on electricity.

Key Advantages of Direct Air Capture

Advocates and scientists highlight several unique strengths of DAC as an emissions reduction tool:

Permanent Carbon Removal: When paired with secure geological storage, DAC can effectively and permanently remove CO₂ from the carbon cycle.
Addressing Legacy Emissions: DAC can target “historical” emissions that are unrelated to today’s activities, offering a means of genuinely reducing atmospheric concentrations.
Flexible Application Locations: Unlike point-source CCS, DAC plants can be sited almost anywhere, as the CO₂ in the atmosphere is globally mixed.
Potential to Balance Hard-to-Abate Emissions: DAC could help offset residual emissions from sectors that are challenging to decarbonize (e.g. aviation, shipping).
Enabling Net-Zero or Net-Negative Pathways: DAC is increasingly seen as critical for scenarios in which humanity achieves not just net-zero, but net-negative emissions to reverse past damage.

The Major Drawbacks and Concerns

Despite its promise, DAC poses high hurdles—especially regarding scaling, environmental impacts, and economic viability:

Energy Intensity: Both solvent and sorbent systems consume significant energy, typically in the form of heat and/or electricity. If this energy comes from fossil sources, the net climate benefit is undermined.
High Cost: Current DAC technologies generally range from $94–$1000 per metric ton CO₂ captured and stored, substantially higher than most emission abatement or nature-based removal practices.
Water and Land Use: Some liquid systems require substantial water; large facilities also have notable land footprints.
Slow Deployment: As of 2023, there were only a handful of large DAC facilities in operation worldwide, capturing tens of thousands of tons per year—well short of the gigaton scale needed.
Permanence and Leakage Risks: Geologic storage appears safe, but public concern persists over potential leaks or improper site management over the long term.
Ethical and Political Concerns: Some worry that focusing on DAC could detract from essential emission reductions, leading to a “moral hazard” where continued emissions are tolerated in anticipation of future cleanup.

Energy Use: A Critical Bottleneck

One of the defining challenges for DAC is the high energy demand per ton of CO₂ removed. Energy requirements range from 1–8 GJ (gigajoules) per tonne of CO₂, depending on the technology used. The consequences of this include:

Upstream Emissions: If DAC facilities are powered with fossil fuels, a significant fraction of the carbon removal is negated.
Pressure on Renewables: Large-scale DAC could compete with other sectors—like transportation, industry, and residential power—for clean energy.
Cost Implications: The need for vast, affordable, reliable clean energy sources both increases the financial burden and introduces infrastructure challenges.

Comparison: Direct Air Capture vs. Other Carbon Removal Methods

Method	Carbon Removal Mechanism	Scalability	Cost (per ton CO₂)
Direct Air Capture	Chemical or physical extraction from air, then storage	Medium (scalable but slow and costly now)	$94–$1000
Afforestation/Reforestation	Plant trees to sequester CO₂ biologically	High (large land required)	$10–$50
Soil Carbon Sequestration	Changes to farming practices to increase soil carbon content	High (depends on local conditions)	$5–$100
Bioenergy with Carbon Capture (BECCS)	Grow biomass, capture and store combustion emissions	Medium	$50–$200

Potential Environmental Impacts

The deployment of DAC at global scale could have ripple effects beyond energy consumption:

Water Use: Liquid-based DAC systems may require significant freshwater, raising concerns in water-scarce regions.
Land Use: While less demanding than afforestation per ton removed, siting many large plants could affect land availability and ecosystem services.
Resource Extraction: Manufacture and operation of DAC equipment may involve mining or processing materials, with associated environmental footprints.
Local Air Quality: The operation of large fans and machinery could generate noise and air movement disturbances, especially in populated areas.

The Future of Direct Air Capture

The major agencies and scientific panels—including the Intergovernmental Panel on Climate Change (IPCC)—see a role for DAC in achieving climate targets, but not in isolation. Policy, funding, and innovation are all required to unlock its potential:

Investment and Innovation: Both public and private investment in research and pilot facilities is rapidly increasing, as is interest from the corporate sector for “carbon removal credits.”
Policy Incentives: Policies that reward durable carbon removal can spur deployment, provided they avoid creating perverse incentives for delayed emissions cuts.
Cost Reductions: Experience with renewable energy suggests that costs could fall as deployment scales up and new materials/techniques are developed.
Integration: DAC will likely need to operate alongside, not in place of, aggressive emissions reductions and nature-based removals for meaningful climate progress.

Frequently Asked Questions (FAQs)

Q: How much CO₂ can direct air capture remove today?

A: As of 2023, global DAC facilities collectively capture less than 20,000 tons of CO₂ per year—orders of magnitude below the gigaton-scale needed for climate impact.

Q: Is the stored CO₂ at risk of leaking back into the atmosphere?

A: Most geologic storage methods are considered very safe for long-term containment, but ongoing monitoring and careful siting are required to maintain security and public trust.

Q: How expensive is direct air capture compared to other climate solutions?

A: DAC is currently among the most expensive carbon removal options, at $94–$1000 per ton. Costs are expected to drop with innovation and scale, but for now it is costlier than nature-based approaches like reforestation.

Q: Can DAC offset all global emissions?

A: DAC is better suited to handle hard-to-abate and legacy emissions, but should not be viewed as a substitute for deep emissions reductions across all sectors.

Q: What role does DAC play in corporate or national net-zero plans?

A: Many organizations are investing in DAC as part of “net-zero” pledges, though best practice is to use it for residual emissions that cannot otherwise be eliminated, and to pair it with proof of permanent CO₂ storage.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

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