Direct air capture: which startup is ahead?
In our CCUS market deck, you will find everything you need to understand the market
SUMMARY
Climeworks is still the direct air capture startup ahead overall, but its lead is now narrow enough that Heirloom could take first place with one successful commercial plant.
The market’s biggest distortion is the gap between what buyers have ordered and what suppliers have delivered. DAC companies had contracted 2.47 million tonnes by mid-2025, while recorded deliveries stood at only 1,186 tonnes.
Climeworks leads because it has removed and stored the most CO₂, operated the largest startup-owned DAC fleet and accumulated years of plant data. Mammoth’s weak early output also shows that installed nameplate capacity is a poor proxy for real removal.
Heirloom has the strongest pure-DAC contract book and the clearest route to overtaking Climeworks. Its planned 17,000-tonne Louisiana plant is the next decisive test: reliable operation would create a near tie, while a later 100,000-tonne phase would likely put Heirloom first.
CarbonCapture and Airhive form the next tier because both have moved beyond laboratory systems. CarbonCapture has first capture at a 2,000-tonne modular site, while Airhive has a roughly 1,000-tonne system in operational ramp-up and has added Carbyon’s sorbent platform.
Mission Zero has built a different kind of advantage. Its three smaller deployments span fuels, building materials and geological storage, giving the company unusually broad integration experience even though it has not yet proved large-scale economics.
Cheap DAC remains unproven. CarbonCapture’s Frontier agreement implies about $440 per contracted tonne, but contract prices include delivery risk, financing, storage and margin, so none of the headline figures should be mistaken for a demonstrated production cost.
Phlair, Avnos and Airhive stand out more for system design than current scale. Phlair can follow intermittent solar power, Avnos produces water while capturing CO₂, and Airhive publishes unusually specific energy and water estimates.
Funding has bought Climeworks a real operating-data advantage, not an unassailable commercial lead. More than $1 billion financed two major plants and several technology generations, but it also exposed expensive scaling problems that smaller competitors have not yet faced.
The ranking will move on measured output, not project announcements. The next meaningful evidence is sustained annual removal from Heirloom’s Louisiana plant, CarbonCapture’s Tamarack modules, Airhive’s Alberta system and Climeworks’ first full Generation 3 project.
For now, the order is Climeworks, Heirloom, CarbonCapture and Airhive. Climeworks has the strongest proof of execution; Heirloom has the strongest credible path to becoming the new leader.
This market map, featured in our CCUS market deck, highlights top companies and startups in the CCUS market
Which direct air capture startups are worth comparing?
The useful direct air capture comparison today contains 12 independent startups with meaningful funding, operating equipment, contracted removals or a credible commercial project.
We focus on companies developing their own DAC process and aiming to supply permanent carbon removal, even when they also sell captured CO₂ for fuels, drinks or materials. Funding totals are minimum publicly disclosed amounts. Private startups often announce one round while keeping earlier grants, strategic investments or project finance confidential.
We exclude 1PointFive because it belongs to Occidental Petroleum. Carbon Engineering and Holocene have been acquired, so they no longer compete as independent startups. Deep Sky provides shared project and storage infrastructure rather than relying mainly on its own capture technology. Skytree and Aircapture are more focused on supplying CO₂ for industrial use, while this comparison gives greater weight to permanent removal.
| Startup | What it is building | Minimum publicly disclosed funding or backing |
|---|---|---|
| Climeworks | Solid-sorbent DAC plants connected to geological storage | More than $1 billion in equity |
| Heirloom | Limestone-based DAC using electric kilns and passive carbonation | At least $203 million, plus later undisclosed strategic investments |
| CarbonCapture | Factory-produced modular DAC machines using replaceable sorbent cartridges | At least $115 million |
| Avnos | Water-positive DAC powered partly by low-grade waste heat | At least $53 million disclosed; more than $100 million in combined backing claimed |
| Spiritus | Passive-air DAC using a low-cost proprietary sorbent | At least $30 million, plus earlier undisclosed funding |
| Mission Zero | Electrochemical DAC requiring electricity but no high-temperature heat | £21.8 million Series A, plus earlier funding |
| Greenlyte | DAC combined with hydrogen and renewable-fuel production | More than $26 million |
| Noya | Modular, water-positive DAC using moisture-responsive chemistry | About $22 million |
| Phlair | Electrochemical DAC designed to run around intermittent solar power | €14.5 million seed round |
| RepAir | All-electric electrochemical DAC for permanent removal | $15 million Series A |
| Octavia Carbon | Modular DAC using Kenyan geothermal power and local geological storage | $5 million seed round |
| Airhive | Mineral-sorbent DAC using fast fluidized-bed equipment | Funding undisclosed |
Is there a clear direct air capture leader today?
Climeworks is still ahead today, although the direct air capture market has become a narrow Climeworks-Heirloom race rather than a one-company category.
The gap between sales and delivery explains why the leadership remains unsettled. CDR.fyi’s latest detailed DAC review counted 2.47 million tonnes contracted between 2022 and the first half of 2025. Only 1,186 tonnes had been delivered. Buyers had therefore ordered more than 2,000 times the volume that suppliers had completed.
Climeworks owns most of the field’s operating history and delivered removals. Heirloom owns the strongest combination of pure-DAC contracts and near-term construction. CarbonCapture and Airhive form the next group because both now have systems operating at around 1,000 tonnes or more in annual nameplate capacity.
Mission Zero has deployed more separate systems than most challengers. Phlair has attracted a large contract at a lower implied price. Avnos has a well-funded commercial demonstration under development. Spiritus has ambitious cost and scale targets but little verified operating evidence.
If you want more recent data on this point, please see our latest CCUS market report.
As this chart shows, and as featured in our CCUS market deck, search interest in carbon credits has grown significantly
Which direct air capture startup has actually removed the most CO₂?
Climeworks has removed and stored the most CO₂ among DAC startups, although Mammoth’s early performance makes the lead look much smaller than its 36,000-tonne nameplate suggests.
CDR.fyi estimated that Climeworks supplied 81% of DAC deliveries recorded by the middle of 2025. That implies roughly 960 tonnes from the industry total of 1,186 tonnes. No independent startup was close.
Mammoth produced 873 gross tonnes during its first thirteen months, according to figures reported by the Financial Times. After emissions from the removal process were deducted, net removal fell to 205 tonnes. Against roughly 39,000 tonnes of proportional nameplate capacity over thirteen months, that equals about 2.2% gross utilization and 0.5% net utilization.
Mammoth was still adding collectors and moving through commissioning, but the shortfall remains severe. A plant promoted around tens of thousands of annual tonnes was initially delivering hundreds.
Heirloom’s Tracy plant has a 1,000-tonne annual rating and has fulfilled customer purchases, but Heirloom has not released a comparable full-year production figure. CarbonCapture’s Tamarack project achieved first capture at a 2,000-tonne site. Airhive started operating its 1,000-tonne Alberta system. Neither has yet published a full year of independently verified removal.
| Startup | Approximate operating nameplate | What has been publicly demonstrated |
|---|---|---|
| Climeworks | About 40,000 tonnes a year | Clear delivery lead; Mammoth reported 873 gross and 205 net tonnes over 13 months |
| CarbonCapture | 2,000 tonnes a year | Tamarack achieved first capture; sustained annual output undisclosed |
| Airhive | About 1,060 tonnes a year | Alberta system operating and Teesside pilot online; sustained annual output undisclosed |
| Heirloom | 1,000 tonnes a year | Tracy operating and supplying customers; full-year verified production undisclosed |
| Mission Zero | About 550 tonnes a year | Three systems operating across the UK and Canada; annual removal totals undisclosed |
Which DAC startup has learned the most from building and running real plants?
Climeworks has learned the most from building and operating complete DAC plants, while Mission Zero has accumulated the broadest range of smaller deployments.
Climeworks has run Orca since 2021 and Mammoth since 2024. Those plants combine air capture, heat, vacuum equipment, CO₂ processing and Carbfix’s underground mineral storage. The company has years of data on weather, maintenance, filter cycles, sorbent degradation and storage integration.
Mammoth’s weak output has also exposed the problems that appear when DAC grows from several thousand tonnes to tens of thousands. Competitors working at pilot scale have not yet faced many of those plant-level constraints.
Climeworks has coordinated construction, geothermal energy, CO₂ handling, measurement and permanent storage across two Icelandic sites. Project Cypress gained further support when the US government released an initial $50 million award shared by the Louisiana project team.
Mission Zero has taken a broader small-system route. Its Sheffield plant supplies CO₂ for fuel research, its Norfolk system connects DAC with building materials, and its Alberta system connects with geological storage. The three deployments expose the same platform to different climates, customers and downstream equipment.
Airhive and CarbonCapture are learning inside Deep Sky Alpha in Alberta, where several DAC suppliers share transport, measurement and storage infrastructure. CarbonCapture’s modular Leo equipment has also moved from a factory concept into a 2,000-tonne operating site.
Heirloom has operated its Tracy facility for more than two years and brought in Chiyoda as an investor and engineering partner for its Louisiana expansion. The next test is whether it can move limestone, run electric calcination and automate the process reliably at 17,000 tonnes.
This chart, included in our CCUS market deck, illustrates yearly VC funding for CCUS startups
Which direct air capture startup has the strongest customers and contracts?
Heirloom has the strongest pure-DAC contract book today, while Climeworks has the largest and most diverse carbon-removal customer network.
Microsoft agreed to purchase up to 315,000 tonnes from Heirloom. Frontier buyers contracted another 26,900 tonnes for $26.6 million. United Airlines Ventures obtained the right to purchase as much as 500,000 tonnes, although that agreement is a purchase option and carries less weight than a firm delivery commitment.
Microsoft’s agreement alone is close to the total annual capacity Heirloom eventually wants to build across its two Louisiana facilities. The demand and construction plans fit together unusually well.
Climeworks has signed prominent buyers across technology, finance and industry. Its disclosed agreements include 40,000 tonnes for Morgan Stanley and 31,000 tonnes for Schneider Electric. Climeworks Solutions also announced 14 new agreements covering roughly 450,000 tonnes during the first half of 2026.
The newer Climeworks figure includes portfolios containing several carbon-removal methods. Some tonnes may come from biochar, enhanced weathering or other suppliers, so the agreements say more about Climeworks’ commercial reach than the demand for its own DAC machines.
CarbonCapture also deserves attention. Frontier buyers agreed to pay it $20 million for 45,500 tonnes. Phlair later secured $30.6 million for 47,000 tonnes. Both contracts came from experienced buyers and include defined delivery volumes.
If you want more recent data on this point, please see our latest CCUS market report.
Which direct air capture startup is gaining ground fastest right now?
Airhive is gaining ground fastest among the DAC challengers currently trying to catch Climeworks and Heirloom.
Airhive entered operational ramp-up at its 1,000-tonne Alberta system, started commissioning a 60-tonne pilot in Teesside and joined Mission Zero in the UnionDAC consortium. UnionDAC targets an initial 20,000 tonnes of annual capacity, followed by another 40,000 tonnes.
Airhive then acquired Carbyon, adding a second technical platform and a team working on fast-cycling thin-film sorbents. The company now combines operating hardware, mineral-sorbent expertise and another route for improving capture speed and energy use.
Phlair is also accelerating. Its 10-tonne outdoor pilot has been operating since early 2025, Frontier is financing a 47,000-tonne offtake, and the company recently added WISAG as a customer and project partner. Phlair is also involved in a phased Norwegian project that could eventually reach 500,000 tonnes, although most of that scale remains on paper.
Spiritus raised a $30 million Series A, established a New Mexico pilot site and continued development around its proposed Wyoming Carbon Orchard. Its passive-air design and sub-$100 target are eye-catching, but public plant data remains limited.
This chart, included in our CCUS market deck, shows why CarbonCure stands out in CCUS
Which DAC startup is closest to making carbon removal affordable?
Nobody has proved cheap DAC yet. CarbonCapture has the lowest implied large contract price, while Airhive and Phlair have the most interesting newer cost evidence.
BloombergNEF has placed current industry capture costs around $900 per tonne. Airhive says credits from built DAC plants have recently remained near $1,000. These numbers remain far above normal carbon-credit prices and the support available from most public incentive programs.
Dividing CarbonCapture’s $20 million Frontier contract by 45,500 tonnes produces an implied price of about $440 per tonne. Phlair’s $30.6 million contract for 47,000 tonnes implies about $651. Heirloom’s $26.6 million agreement for 26,900 tonnes comes to roughly $989.
Contract prices can include financing, verification, storage, delivery risk and margins, so they should not be confused with production costs. CarbonCapture’s price is still notable because an experienced buyer accepted it for a large, defined volume.
Airhive expects its Alberta system to capture CO₂ for less than $500 per net lifecycle tonne after ramp-up, excluding transport and storage. Climeworks targets $250 to $350 per captured tonne by 2030 after missing earlier cost-reduction goals. Spiritus claims a pathway below $100, but its public evidence currently comes from modelling and technical targets.
| Company or benchmark | Approximate public price or cost | How much confidence should we place in it? |
|---|---|---|
| Current DAC industry | Around $900–$1,000 per tonne | Based on market estimates and existing DAC credit prices |
| CarbonCapture and Frontier | About $440 per contracted tonne | Strong buyer evidence, though future delivery risk remains |
| Airhive Alberta system | Below $500 per net captured tonne | Company calculation excluding transport and storage |
| Phlair and Frontier | About $651 per contracted tonne | Strong buyer evidence for future deliveries |
| Heirloom and Frontier | About $989 per contracted tonne | Strong buyer evidence from an earlier first-of-a-kind contract |
| Climeworks | $250–$350 per captured tonne targeted | Future target that still needs plant-scale proof |
| Spiritus | Below $100 per tonne targeted | Early company projection with little operating validation |
If you want more recent data on this point, please see our latest CCUS market report.
Which direct air capture technology uses energy and water best?
No DAC startup has proved the best full-system energy and water performance, although Phlair, Avnos and Airhive currently have the clearest differentiated designs.
Climeworks has produced the strongest large-scale test data. Its Generation 3 equipment completed more than 1,300 cycles using structured adsorbents developed with Svante. Climeworks reported twice the capture capacity and half the energy use of its previous design. The company is aiming for roughly 1.5 megawatt-hours per tonne.
Phlair also targets less than 1.5 megawatt-hours per tonne. Its electrochemical process can separate regeneration from air contact, allowing parts of the system to follow cheap solar generation while stored liquids keep the capture process running. That flexibility could matter as much as the headline energy number.
Airhive publishes unusually specific resource figures. Its 1,000-tonne system is expected to use around 2 megawatt-hours per tonne across capture and regeneration. Water consumption reaches a maximum of 0.6 kilograms per kilogram of CO₂ in dry air and falls as humidity rises. The company says no additional water is required at 100% humidity.
Avnos has the strongest water proposition. Project Cedar is designed to capture 3,000 tonnes of CO₂ and produce more than 6,000 tonnes of clean water each year. Its process can also use low-grade waste heat, which creates a possible fit with data centers and industrial sites that already need cooling and water.
Mission Zero avoids high-temperature regeneration and has demonstrated a system powered entirely by solar electricity in Alberta. The published figures remain too uneven for a clean ranking because companies use different boundaries for electricity, heat, construction and storage.
This chart, included in our CCUS market deck, illustrates yearly funding for CCUS startups
Is Climeworks turning its huge funding advantage into a real DAC lead?
Climeworks has converted more than $1 billion into the field’s deepest operating record, but the resulting DAC lead is far weaker than that funding advantage suggests.
The money funded Orca and Mammoth, two commercial equipment generations, a large innovation center, certification work and relationships with many of the world’s largest carbon-removal buyers.
It has also funded expensive mistakes and slow ramp-ups. Mammoth’s early utilization remained below 3% on a gross basis, while net removal was lower again. Climeworks later cut a meaningful share of its workforce as capital became harder to raise and several government-backed projects faced uncertainty.
The company still raised another $162 million and has enough resources to redesign its technology. Generation 3 performed well across more than 1,300 test cycles, with reported capture capacity doubling and energy consumption halving. Those gains now need to appear inside a full commercial plant.
Climeworks’ expansion into managed removal portfolios provides revenue and keeps corporate buyers close, though it makes commercial growth less dependent on the performance of Climeworks’ own DAC technology.
Can Heirloom overtake Climeworks in direct air capture?
Heirloom can overtake Climeworks, and its first 17,000-tonne Louisiana plant will decide whether the challenge is real.
Heirloom’s website still presents that facility as coming online in 2026. Full commercial operations have not yet been publicly demonstrated, so the plant remains a construction milestone rather than operating capacity.
A 17,000-tonne facility would be seventeen times larger than Heirloom’s Tracy plant and equal to roughly 42% of Climeworks’ current operating nameplate.
Heirloom then plans a 100,000-tonne phase, followed by another 200,000 tonnes. Reaching the first two phases would give it around 117,000 tonnes of annual capacity, nearly three times the combined ratings of Orca and Mammoth.
Microsoft’s 315,000-tonne agreement gives Heirloom a buyer for almost the same volume as its wider Louisiana plan. Few DAC startups have aligned one major customer with one major buildout so neatly.
The engineering risk remains high. Heirloom is attempting a seventeenfold first jump, followed by another increase of almost six times. Reliable operation at 17,000 tonnes would bring it close to a tie. Successful operation above 100,000 tonnes would probably put it first.
If you want more recent data on this point, please see our latest CCUS market report.
This chart, included in our CCUS market deck, compares the main business model options for carbon capture project developers
Is CarbonCapture the best modular DAC startup?
CarbonCapture is the strongest modular DAC startup today because Tamarack has moved the Leo design from a factory concept to an operating 2,000-tonne site.
Each Leo unit fits inside the dimensions of a shipping container and is rated above 500 tonnes annually. Tamarack therefore represents roughly four modules working as one project, creating a useful test of repeatable manufacturing, installation and maintenance.
CarbonCapture can change sorbent cartridges rather than tying every machine permanently to one material. Better sorbents could enter an established hardware platform without forcing the company to rebuild the whole system.
We still need to know how often the modules operate, how quickly sorbents degrade, how much maintenance each container requires and whether the factory can produce dozens of identical units at a predictable cost.
Tamarack has achieved first capture. A full year of high availability would carry much more weight.
What can the leading DAC startups do that rivals cannot easily copy?
Climeworks has the strongest operating-data advantage, while Heirloom and CarbonCapture may have systems that are easier to industrialize.
Climeworks has years of maintenance records, weather data, filter-cycle information and storage experience from Iceland. A competitor can buy similar fans and study similar sorbents. Recreating years of failure data and operating adjustments takes much longer.
Heirloom’s raw material is ordinary limestone, yet the process around it is specialized. The company must control carbonation speed, particle handling, hydration, calcination, heat recovery and automation across millions of repeated cycles. Its partnerships with electric-kiln and engineering specialists add knowledge that cannot be copied from a patent alone.
CarbonCapture’s advantage could come from manufacturing. A standardized machine, qualified suppliers and repeatable servicing procedures can create a stronger position than one exceptional sorbent. Its cartridge approach also gives the company flexibility when materials improve.
Airhive now combines fluidized-bed engineering with Carbyon’s fast-cycling sorbent research. Mission Zero has patents and experience connecting its electrochemical process to three different downstream uses. Phlair is building around load flexibility. Avnos combines CO₂ capture, water production and waste-heat use inside one system.
Large industrial companies remain a serious threat to every startup. Occidental already owns Carbon Engineering and is building through 1PointFive. Oil, chemical and engineering groups have the capital, subsurface knowledge and project teams required for large plants.
This chart, featured in our CCUS market deck, illustrates revenue distribution by customer segment in the CCUS market
Can we trust the numbers published by direct air capture startups?
We can trust verified stored tonnes. Nameplate capacity, cost targets and distant project pipelines require much more caution.
The strongest evidence is a measured tonne that has been captured, stored and independently certified. Full-year plant production comes next because it reveals downtime, energy consumption and maintenance under real conditions.
A binding offtake with a defined buyer, quantity, price and delivery period is useful commercial evidence. A purchase option, reservation or memorandum of understanding carries less weight because the buyer may never take the full volume.
Nameplate capacity only describes the plant’s intended output. Mammoth’s rating and early net production were separated by two orders of magnitude. The same caution should apply to every planned Heirloom, Phlair, Spiritus or CarbonCapture facility.
Cost figures also need clear boundaries. Capture alone excludes compression, transport, storage, verification, financing and some lifecycle emissions. A contract price can differ substantially from the supplier’s production cost.
Which direct air capture startup is actually ahead?
Climeworks is still the direct air capture startup ahead overall today, with Heirloom close enough to take first place if its Louisiana plant works as planned.
We give Climeworks the lead because it has delivered the most removal, operated the largest startup-owned DAC fleet, learned from complete capture-and-storage plants and built the broadest commercial organization. Its recent plant performance prevents a comfortable victory.
Heirloom comes second through its contracts, financing and credible path toward much larger capacity. It remains behind because its planned scale has not yet become verified production.
CarbonCapture takes third through Tamarack and a genuinely repeatable modular design. Airhive follows closely after a rapid sequence of deployment, technology development, project partnerships and acquisition activity.
Mission Zero ranks fifth because it has repeatedly put machines into different operating environments. Phlair ranks sixth because its commercial contract and energy design are strong, although its current pilot remains tiny. Avnos has a well-backed 3,000-tonne project under development. Spiritus has high upside but much thinner operating evidence.
Heirloom’s 17,000-tonne plant is the most likely event to change first place. Climeworks’ next Generation 3 project is the strongest opportunity to widen the lead again.
| Rank | Startup | Why it ranks here now | What would change the ranking |
|---|---|---|---|
| 1 | Climeworks | Leads verified delivery, operating experience, installed nameplate and customer access | Strong Generation 3 plant performance would secure the lead; continued weak utilization would threaten it |
| 2 | Heirloom | Strongest pure-DAC contracts and most credible large startup construction pipeline | Reliable operation at 17,000 tonnes could create a near tie; 100,000 tonnes would probably put Heirloom first |
| 3 | CarbonCapture | Operating 2,000-tonne modular site, repeatable hardware design and strong contracted pricing | Needs a full year of reliable output and several replicated sites |
| 4 | Airhive | Fastest recent momentum, operating 1,000-tonne system, UnionDAC role and Carbyon acquisition | Independent validation of its sub-$500 cost could move it into the top three |
| 5 | Mission Zero | Three deployed systems across different uses and climates | Needs to convert small deployments into a plant above 10,000 tonnes |
| 6 | Phlair | Large Frontier contract, load-flexible electrochemistry and attractive implied price | Must move from a 10-tonne pilot to commercial delivery |
| 7 | Avnos | Well-backed 3,000-tonne Project Cedar and a distinctive water-positive design | Project Cedar must enter operation and publish energy, water and output data |
| 8 | Spiritus | Strong investors, passive-air design and ambitious cost targets | Needs independently measured pilot performance before its megatonne plans carry weight |
| 9 | Octavia Carbon | Strong geothermal and geological-storage position in Kenya | Commissioning of its 1,000-tonne project must become verified annual removal |
| 10 | Greenlyte | Commercial partnerships and a differentiated DAC-plus-hydrogen system | Needs more evidence of permanent removal rather than fuel-focused CO₂ use |
| 11 | Noya | Credible funding and a water-positive modular approach | Recent commercial deployment evidence remains limited |
| 12 | RepAir | Promising all-electric electrochemical process | Needs a larger operating system, binding demand and public performance data |
If you want more recent data on this point, please see our latest CCUS market report.
This chart, included in our CCUS market deck, shows how carbon removal marketplace technology has evolved over time
OUR METHODOLOGY
This analysis asks which independent direct air capture startup is ahead based on evidence available today. We compare demonstrated carbon removal, operating experience, customer commitments, deployment momentum, affordability, energy and water performance, industrial scalability and the advantages that may be difficult for rivals to reproduce.
We include companies developing their own DAC process and pursuing permanent carbon removal, even when they also supply captured CO₂ for fuels, drinks or materials. The comparison covers 12 independent startups with meaningful funding, operating equipment, contracted removals or a credible commercial project.
We exclude 1PointFive because it belongs to Occidental Petroleum. Carbon Engineering and Holocene are no longer independent after being acquired. Deep Sky is treated as shared project and storage infrastructure rather than a primary DAC-technology developer, while Skytree and Aircapture are more focused on industrial CO₂ supply.
Verified captured and permanently stored tonnes receive the most weight. Sustained plant operation comes next because it reveals availability, maintenance, energy use, sorbent performance and the gap between nameplate capacity and real production.
Commercial agreements are assessed by their structure. Binding offtakes with a named buyer, defined volume, price and delivery period carry more weight than reservations, purchase options or memoranda of understanding. Contract prices are treated as commercial evidence, not as direct production-cost estimates.
Planned facilities, nameplate capacity and cost targets are used to assess future potential, but they do not count as current operating performance. Funding totals are minimum publicly disclosed amounts and may exclude grants, debt, project finance, strategic investments or earlier rounds that were not fully disclosed.
The final ranking combines the individual Q&A conclusions rather than relying on one metric. A company can rank highly through delivered removal and operating data, through contracts and near-term construction, or through repeatable hardware and credible deployment. Claims without plant-scale evidence receive less weight.
Key market-wide evidence comes from CDR.fyi’s 2025 Direct Air Capture Market Snapshot, which provides the comparison between contracted and delivered tonnes and Climeworks’ share of recorded DAC deliveries.
Important company and transaction sources include Climeworks’ Generation 3 testing results, Climeworks’ technology and cost targets, Heirloom’s Louisiana project overview, Heirloom’s Microsoft agreement, Frontier’s Heirloom offtake profile, Frontier’s Phlair offtake profile, CarbonCapture’s Leo platform, CarbonCapture’s Tamarack project, Airhive’s operating-project portfolio, Airhive’s Carbyon acquisition, Mission Zero’s deployment report, Avnos’ Project Cedar announcement, and the US Department of Energy’s Project Cypress award.
In our CCUS market deck, we identify pain points entrepreneurs should prioritize
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