This graphic illustrates the historical investment in decarbonization. It’s important to note that the U.S. has been using and transporting CO₂ since the 1970s, primarily for enhanced oil recovery (EOR) in depleted oil and gas reservoirs. EOR uses CO₂ to help get more oil out of old oil fields by pumping the CO₂ into the ground.

Following the work of the Intergovernmental Panel on Climate Change (IPCC) in the 1980s and 1990s on tracking and mitigating human-caused climate change, there was a growing effort to invest in understanding decarbonization, particularly engineered solutions. 

In the early 2000s, the Department of Energy established what were called the Regional Carbon Sequestration Partnership Programs. While the name is a mouthful, the key idea was exploring opportunities to manage CO₂ at a regional scale, such as the Southeast or Western U.S. These programs lasted over 15 years and generated a lot of the knowledge we now rely on: how to safely capture CO₂, transport it, and store it deep underground. These legacy investments helped de-risk the broader carbon management ecosystem, which is vital to enabling large-scale DAC deployment.

In the early to mid-2000s, there was increasing investment in research focused on bench-scale studies, looking at material suitability for DAC. This marked a shift from capturing CO₂ from point sources (like industrial facilities) to capturing it directly from the atmosphere. Significant investment in DAC really started around the 2010s. In 2018, tax credit enhancements provided meaningful financial incentives to support DAC technology development. As a result, many projects began constructing DAC units and working to move from bench scale to more commercial-scale operations.

In the 2020s, we’ve seen historic investments through the Infrastructure Investment and Jobs Act (also known as the Bipartisan Infrastructure Law) and further tax credit enhancements through the Inflation Reduction Act. As of 2024, over 276 carbon management projects have been announced in the U.S., building on decades of research and investment, and playing a key role in DAC deployment.

The landscape has transitioned from bench-scale research to full demonstrations of DAC units. This includes evaluating design efficiencies and cost savings as we move toward commercialization.

A key example is the DAC Hub Program, funded through the Infrastructure Law. Congress allocated over $3.5 billion to support DAC projects with the goal of understanding how to deploy them at scale across the country.

The funding opportunity included three topic areas:

• TA-1 focused on feasibility: exploring where DAC could be deployed and what technologies are best suited to specific geographies and resources.
• TA-2 focused on design: these projects already know which DAC technologies they want to use and have data on regional resource availability and suitability.
• TA-3 focused on advanced-stage technologies: ready for engineering design, material procurement, and construction.

The number of projects awarded in each category:

• 14 for feasibility (TA-1),
• 5 for design (TA-2), and
• 2 for advanced development (TA-3).

In total, 21 DAC hubs were selected across the U.S., as shown in the graphic below. Initial investments totaled $1.1 billion, with the potential to advance into development phases, if the business case and designs are successfully proven.

Early, distributed DAC (5-10 years):

At first, DAC facilities will likely be small-scale, located in rural or industrial areas, where we can test feasibility and performance. Also early on, some businesses might see competitive advantages in removing CO₂ from the air. In that case, we could start to see early deployments closer to where people live and work. This could benefit the community by reducing truck traffic, but it might also raise concerns: the DAC units could produce noise, or affect the visual appeal of the neighborhood.

Maturing DAC installations (12-20+ years):

As the technology proves itself, we’ll start to see larger, industrial-scale sites emerge. These sites would require access to renewable energy and water, and they’d likely be located near CO₂ storage infrastructure, such as geological injection sites or mineralization locations, or near facilities that utilize CO₂ as a resource. They’d likely be built away from major population centers, though they would still require a nearby workforce. Operating these larger DAC hubs will also require new infrastructure, like roads and pipelines, which could be seen as either a benefit (economic development) or a concern (environmental impact), especially in areas that are currently undeveloped.

Long-term DAC (25-50+):

Looking further into the future, we might start to see DAC facilities fully integrated into the fabric of communities. DAC could be part of everyday life: CO₂ is captured, stored underground, and used in manufacturing goods. This kind of system would rely heavily on expanded infrastructure, especially CO₂ pipelines, and large-scale planning.

So across all of these phases, early-stage testing, intermediate-scale industrial sites, and long-term community integration, DAC will require resources: energy, water, and land.

As DAC hubs grow, they will initially start small, but eventually scale up significantly. The key resource considerations include:

• Energy, especially renewables (which are already in high demand)

• Water use

• Land use, including potential impacts on biodiversity

• Infrastructure demands: roads, pipelines, and even housing

Broadly environmental community groups have deemed DAC as well as other industrial forms of carbon removal as “false solutions” because they have failed to meaningfully reduce emissions while allowing polluting industries to continue business as usual.

We have a growing demand for energy due to a growing population, and this demand is increasing even faster than expected, thanks in part to widespread AI use and the rapid development of data centers. So, fossil fuels are going to remain part of our energy landscape for a while. If we imagine a carbon-free society in the near term, say 10, 20, or 30 years down the road, it would require all of us to drastically reduce our energy use, instead of continuing the lifestyles we've grown accustomed to. Because of this, proponents of DAC believe that carbon-based energy will be with us for most of our lifetimes, and the only way we can continue using it responsibly is by cleaning it up, through solutions like DAC.

But the way we implement those solutions matters, if we’re not thoughtful, they could result in net negative outcomes. So intention and process are critical to ensuring that DAC and other technologies actually deliver climate and community benefits. One thing we do need to be cautious about, though, is if DAC begins using large amounts of renewable power, but we continue running legacy fossil plants without carbon capture, that’s not a good outcome. If we're using energy to run DAC but still relying on unmitigated fossil power, we risk increasing emissions, which defeats the purpose. We must move hand in hand, deploying renewables while also retiring high-emitting sources. And, we also need to reduce other air pollutants that accompany these fossil sources. Additionally, building dedicated renewable assets just for DAC may not be the best strategy. That could divert renewable resources from other users. Instead, we need to invest in scalable grid infrastructure that allows renewables to deliver maximum carbon and community benefits.

"Early stages," means we’re still doing laboratory experiments to understand what kinds of chemicals are involved in these materials as they degrade. The next stage would involve the five to ten small deployments around the world that are currently using, for example, amine-based chemicals. We’d then want to visit those sites to see if we can detect similar chemicals at these small pilot facilities. That data is what we would eventually need, so that when a larger site is proposed, like one of the DAC hubs, we can use that information to inform discussions with the community about potential chemical exposures. Early stages means we're still at the point of not fully knowing what those chemicals might be, and we’re trying to figure that out now in the lab.

From a research perspective, we need to know what questions we should be asking about those technologies as we move them forward, so that we don't, through a lack of attention because we’re focused on the science and engineering, end up doing something that we later realize, “Oops, that was really shortsighted; we could have done something differently early on and changed direction.” So we have to be mindful, not just looking at the current suite of technologies, but also figuring out the right questions to ask so we can understand what future technologies will or should be constrained by. One of the key goals of the Community DAC series has been to ask: "What are the right community and environmental questions to raise at the very early stages of research?” These questions that might then become part of the design criteria, alongside things like cost or how much carbon can be captured.

When a technology is commercially deployed, it should have achieved a Technology Readiness Level (TRL) of 8 or 9. A technology that has achieved TRL 9 is one that has been incorporated fully into a larger system. It has been proven to work smoothly and is considered operational.

Direct Air Capture (DAC) systems require energy to remove carbon dioxide (CO₂) from the air. The type and amount of energy needed depend on the specific DAC technology being used, but in general, DAC systems require both electricity and heat. In practice they tend to have dedicated combined heat and power (CHP) systems which generate both electricity and heat simultaneously, making them more efficient.

While any energy source could technically power a DAC system, using renewable energy, such as solar, wind, geothermal, or hydropower, is ideal to minimize the environmental impact. Using non-renewable energy sources like coal or natural gas could result in carbon emissions, which would reduce the climate benefits of DAC.

Some DAC systems also use waste heat, which is excess heat produced by industrial processes or power plants that would otherwise go unused. For example, Climeworks' first industrial-scale DAC plant in Switzerland, which captures about 900 tons of CO₂ per year, is powered by heat and electricity from a waste incineration facility. The facility aims to supply up to 90% of the DAC plant’s energy needs through process heat, with about 50% of that heat coming from organic waste, making it partially renewable. However, we don’t have specific details on whether this goal was fully achieved or on the other energy sources used by this particular DAC plant (Climeworks). Another example is Climeworks' DAC plant in Iceland, which uses geothermal energy, a renewable energy source that harnesses heat from beneath the Earth's surface.

The total amount of energy required for Direct Air Capture (DAC) depends on the size of the facility and how much CO₂ it captures.

For example, Climeworks’ DAC facility in Switzerland requires about 2,000 kWh of energy per metric ton of CO₂ captured (Beuttler et al. 2019) which is comparable to about 2–3 months of an average US household’s natural gas consumption (Source: World Resources Institute). 

The part of the process that consumes the most energy depends on the type of DAC technology used. There are two main approaches:

1. Solid Sorbent-Based Systems: These systems use solid materials (sorbents) that chemically bind with CO₂. Air is passed over these sorbents, capturing CO₂, which is then released when the material is heated or placed under low pressure. The most energy-intensive part of this process is regenerating the sorbent material and releasing the captured CO₂. Example: Climeworks’ DAC plant in Iceland uses a solid sorbent-based system.

2. Liquid Solvent-Based Systems: In this approach, air is brought into contact with a liquid solution that absorbs CO₂. The CO₂-rich solution is then processed to separate and collect the CO₂, allowing the solvent to be reused. The highest energy demand in this process comes from regenerating the solvent and releasing the captured CO₂. Example: Carbon Engineering’s DAC plant in Canada uses a liquid solvent-based system (Singularity Hub).

In both cases, the energy required for releasing CO₂ from the sorbents or solvents is the largest portion of the total energy demand.

DAC systems require a lot of energy to operate. The biggest concern is making sure they don’t take too much energy from the grid, which could cause blackouts or brownouts in local communities. A blackout is when the power goes out completely, and a brownout is when the power gets weaker, making lights dim and devices not work right. To support energy needs without straining the power grid, integrating dedicated energy sources, such as solar farms and battery storage systems, can help meet the energy demands of DAC facilities. Additionally, DAC developers can work closely with utility providers to conduct load analyses and ensure that operations do not negatively impact local power supply. This proactive planning helps maintain grid stability and prevents disruptions.

Yes, DAC can emit CO₂ during its operation, depending on the energy sources used to power the system. The type and amount of energy needed depend on the specific DAC technology being used, but in general, DAC systems require both electricity and heat. If this electricity comes from fossil fuel sources (like coal or natural gas power plants), then the DAC system will have an associated carbon footprint from the energy it consumes. Some DAC plants burn fuels to generate the heat and power they need. This combustion releases CO₂, which may or may not be captured, depending on the plant's setup.

To account for these emissions, DAC discussions often refer to two key terms:

• Captured CO₂: The total amount of CO₂ captured from the air.
• Net Captured CO₂: The actual amount removed, including the amount captured, subtracting any emissions produced during the process.

Direct Air Capture (DAC) systems use chemicals to help remove carbon dioxide (CO₂) from the air. The type of chemicals used depends on the specific DAC technology being used.

Many of the chemicals used in Direct Air Capture (DAC) are common industrial chemicals that are already handled with established safety protocols in large-scale facilities. For example, DAC systems often use sodium hydroxide or calcium hydroxide, both are strong bases that help capture carbon dioxide (CO₂) from the air. While these chemicals can be caustic, meaning they can cause burns or irritation, they are regularly used in industrial processes with risk management measures in place. While the risks associated with handling them are no greater than those in many industries today, maintaining reliable safety protocols would be crucial during the operation of these types of DAC facilities.

Some DAC companies use a different approach, relying on amine-based chemistry. Amines are chemical compounds that can absorb CO₂, but over time, they break down, which can release small amounts of ammonia or urea. These substances can have strong odors, and in high concentrations, they can be harmful. However, DAC facilities are not the same as ammonia or urea production plants; those factories make large amounts of these chemicals, whereas DAC systems may release only small traces as by-products of material breakdown.

A Direct Air Capture (DAC) facility is an industrial site that requires energy to operate, which can come from fuels or electricity. Like other industrial facilities that use fuels, there are potential fire or explosion risks. However, industries have established safety protocols for handling fuels, similar to those used at gas stations or power plants. While no industrial process is entirely risk-free, these risks are not unique to DAC and are managed using well-known safety measures.

Comparing Direct Air Capture (DAC) to natural methods like trees and reforestation is challenging because they serve different purposes. DAC is specifically designed to remove carbon dioxide (CO₂) from the air, while trees provide a range of environmental benefits beyond carbon capture, such as supporting biodiversity and improving soil health. They also differ in cost, land use, capture efficiency, storage methods, and measuring techniques.

One key difference is cost: planting trees is much cheaper than building DAC facilities. However, trees cannot grow everywhere, whereas DAC plants can be placed on land that is not suitable for forests.

In terms of efficiency, DAC is much more effective at capturing CO₂ per square meter of land (although trees are more efficient per dollar). DAC also requires an external energy source, while trees rely on sunlight.

The way CO₂ is stored also differs. DAC captures CO₂ in a pure form, which can then be pressurized and stored underground for permanent removal. Trees store carbon in their biomass, but this is not permanent, as when trees die or decompose, some of the stored carbon is released back into the atmosphere.

Finally, measuring carbon capture is more straightforward for DAC because the amount of CO₂ removed can be directly monitored through pipelines. In contrast, tracking carbon storage in trees is more complex and requires indirect estimation methods.

The amount of land required for DAC depends on the technology, but it is likely to be very significant for large-scale operations since it requires that air be moved over a large surface area at low velocity, and it requires some atmospheric mixing before you can remove more CO2 from the same flow. Overall, if we implemented DAC at the scale necessary to capture CO2 that would make a difference in the atmosphere, or offset significant industrial emissions, we would need areas that are similar to those proposed for solar or wind farms.

Some DAC technologies consume water as part of their capture processes. DAC requires water because some of its processes rely on chemical reactions that involve water or expose water to moving air, leading to evaporation. In humid climates, the higher moisture in the air can reduce water loss for some technologies, also reducing evaporation. However, for solid-based systems, high humidity can slow down the process because cooling takes longer, which can reduce efficiency.

Yes, some other pollutants in the air might need to be removed before capturing CO₂. First, tiny solid particles need to be filtered out so they don’t clog or damage the machine that captures CO₂. This is kind of like how a dryer has a lint trap to catch fuzz from clothes. Over time, we would need to clean these filters so the machine keeps working well. There are also other gases in the air, like sulfur oxides (SOx) and nitrogen oxides (NOx), which don’t have to be removed but can make the CO₂ capture process less effective. These gases can slowly wear down the materials used to capture CO₂, making the process less efficient over time.

The the cost per ton of CO₂ removed by the most well-known Direct Air Capture (DAC) processes varies significantly depending on the company, technology, scale, and energy source (CDR.fyi) The Swiss company Climeworks provided a quote of $500 - 600/tonCO2 for the cost of removal (New York Times).

This is one of those examples of how quickly the industry is innovating. A number of advanced cement formulations are being developed (e.g., geopolymer cement, self-healing cement that reacts with CO2, expandable metal seals). Essentially, the wellbore material isn't necessarily different but materials are being developed that address the weak/pain points (well plugging/abandonment).

Likely, there will be removing parts of the contactors to replace them on a regular basis.  These contactors would be shipped back to a manufacturing facility to be regenerated.  This facility would have to have a solvent recovery and reuse plan and would be likely generating levels of non-hazardous.

Current analyses of DAC systems focus on two key performance metrics:

1. CO₂ removed from the atmosphere, and
2. Net CO₂ removed, which accounts for emissions associated with the energy required to run the system.
    

For example, if a DAC system runs on natural gas, the actual net CO₂ removed may only be one-third to two-thirds of the amount it captures, depending on how much carbon is emitted in the process.

So, the energy source matters a lot. That’s why net removal is the metric used by the Department of Energy and others. Many DAC developers today are looking for low-cost renewable energy to power their systems.

There was a recent case where a DAC project planned to site in North Dakota but chose not to move forward because they couldn’t compete with electricity demand from data centers. That’s the kind of challenge we’ll continue to see.

In the U.S., it would be unwise not to leverage our existing infrastructure to scale DAC in the near term. But if we’re talking about scaling to millions or tens of millions of tons, that will require new energy infrastructure, and it’s critical that this infrastructure is not carbon-intensive. Otherwise, we’re just undoing our own progress.

The equipment is usually much bigger than people. Some machines needed for DAC, like the ones from 8 Rivers, can be as long as a football field (100 meters) and about as tall as a one-story house (10 meters), but they are not very wide. Other machines, like those for Air Capture, are much smaller - a few meters wide and about as tall as a tall person (3 meters). Some machines look like thin buildings, while others are more like short, chunky towers that can fit on a big truck.

These machines probably won’t be built in neighborhoods. They are more likely to be placed in open areas, kind of like wind turbines. But unlike wind turbines, these machines are shorter and don’t have big spinning blades, so they won’t stand out as much. Since they won’t be in neighborhoods and don’t change the view too much, they probably won’t affect home prices or community projects.

Hurricanes could damage the DAC equipment, but the machines are designed to let air pass through them easily so strong winds don’t push too hard against them. Flying debris (like tree branches or signs) could still cause damage. Any electricity system disruptions associated with extreme weather events can also disrupt DAC operations.

Hot and humid weather can affect how well the machines work, but it depends on the type of technology being used. Some machines work faster in the heat but might not be able to hold as much carbon. Also, very hot weather could wear down the materials faster, but scientists are studying this and finding ways to control the damage.

Most DAC (Direct Air Capture) facilities are built in places with very few people and good underground storage for CO2. Some countries, like Norway and Iceland, also have strong climate policies that encourage building these facilities. Different countries use different ways to encourage companies to reduce pollution. Some offer rewards (like tax breaks), while others have strict regulations(like extra taxes on pollution).

Climeworks’ Iceland Orca DAC system has advantages over the Hinwil pilot plant in Switzerland for a few reasons. Iceland has special rocks called basalt that help store CO2 underground. It also has a lot of geothermal energy, which is a clean and renewable energy source. This means Iceland’s system can run on low-carbon energy, making it more efficient. The Hinwil facility utilized waste heat from a garbage incineration system and supplied the CO2 to a nearby agricultural greenhouse. Although this design is not as suitable for permanent CO2 storage, it served as a proof-of-concept and contributed to future developments such as the facilities in Iceland. 

It is very unlikely that DAC will be deployed at scale in metropolitan areas. The key infrastructure requirements for DAC will depend on whether it is being used for sequestration and enhanced oil recovery (EOR) or if it is used for other forms of utilization. In the former case the geology will dictate where it can be deployed along with the appropriate permitting of sequestration wells. Therefore, DAC is likely to happen in locations such as the shale formations in Texas, Pennsylvania, and North Dakota where EOR may already be deployed and there is the workforce and familiarity with the drilling of wells.

Coastal locations could be used if offshore sequestration were to be developed, the liquefaction of CO2 could be carried out at expanded liquified natural gas (LNG) facilities in the U.S. The reverse revaporization of LNG at the receiving ports affords cold temperatures that can be used to enhance DAC efficiency but this would likely be outside the U.S.

For utilization at small scales carbon dioxide could be used for flash freezing and refrigeration of foods. This would not require any new infrastructure as CO2 is already used for these purposes and storage and tankers can be constructed if this were to be expanded. The Technology Readiness Level (TRL) of this type of utilization is high.

DAC has not yet been deployed at a scale large enough to fully understand how these systems interact with major weather events. If we were to deploy in places like the Gulf Coast, where hurricanes are a concern, we would expect DAC facilities to be engineered to withstand those conditions. Currently, no one is proposing DAC systems that are especially tall or structurally unique; they'll likely be 10–20 meters high, comparable to other industrial structures in hurricane-prone regions. So the construction standards already in place for chemical plants should apply. In terms of extreme temperatures or humidity, most DAC systems are designed to shut down if conditions exceed safe operating limits.

1. Noise Management

One modality of DAC uses fans to blow air through the system. These fans will inevitably produce some level of noise. If these systems are placed within or near communities, that noise becomes a factor that must be addressed. Evaluation is needed to determine whether noise mitigation is feasible, or whether alternative DAC designs are preferable. It’s worth noting that these fans don’t rotate at extremely high speeds, they don’t require high air velocities, but they will still generate consistent background noise.

2. Local CO₂ Reduction

DAC systems remove CO₂ from the atmosphere, which means the air exiting the device has a lower CO₂ concentration than the air entering. How far this CO₂-depleted air travels depends on local atmospheric mixing, but under some conditions, the effect could persist for several hundred meters. Most systems are expected to reduce CO₂ by about 200 parts per million at the output. This is not harmful, pre-industrial CO₂ levels were around 270 ppm, but it could become a concern if DAC units are placed next to agricultural operations. Crops like corn depend on ambient CO₂ for growth, and temporary reductions could affect productivity in adjacent fields.

3. Chemical Use and Emissions

Many DAC systems use chemical agents, such as strong alkalis or amines (which have ammonia-like properties). These can degrade over time within the system. Since DAC involves pulling large volumes of air through these devices, there is the potential, albeit modest, for chemical releases into the environment. That said, based on the design of these systems, the volume of any such emissions is expected to be relatively low. Significant degradation and loss of chemicals would be inefficient and costly, so the systems are designed to minimize this.

4. Water Impacts

Some DAC technologies remove water vapor from the air as part of their operation. Others may return water to the air, depending on the specific process and local humidity levels. These effects are difficult to generalize. On humid days, removing moisture might be beneficial; on dry days, it could exacerbate arid conditions. So the net environmental impact on humidity will vary by location and weather, but it’s important to acknowledge that DAC can influence local atmospheric moisture.

5. Plant and Pipeline Safety

Finally, there are concerns related to the storage and transport of captured CO₂, particularly via pipelines. Since CO₂ is heavier than air, a rupture in a pipeline could result in CO₂ pooling in low-lying areas. This poses a serious health risk, as high concentrations of CO₂ can displace oxygen and potentially lead to asphyxiation. There have already been a few incidents involving CO₂ pipeline ruptures, so careful safety planning and regulation will be critical as deployment expands.

Tens to hundreds of millions of tons of CO₂ can be stored geologically. Right now, we know geological storage better than utilization, but that can change as more utilization technologies develop and more research is done. Scientists are trying to find more ways to use CO₂ in things like plastics (which are made from a type of material called polymers traditionally sourced from petrochemicals). Some companies also use CO₂ to help get more oil out of old oil fields by pumping the CO₂ into the ground. This is called Enhanced Oil Recovery (EOR). But researchers are especially focused on using CO₂ to make new products so that we don’t just store it but actually put it to good use. Right now, storage is more typically done than usage, but in the future, we might utilize more CO₂ in useful ways.

Deciding whether to use captured CO₂ in a product or store it underground depends on a few things: the cost of the process, the technology in place, and the regulations in place. Right now, many projects use captured CO₂ to help get more oil out of the ground. This is called Enhanced Oil Recovery (EOR). This makes it easier to get more oil, but some people don’t like it because it continues our dependency on fossil fuels (Carbon180). EOR helps make money, while storing CO₂ underground doesn’t have the same financial benefit. Also, EOR is included in the US Sequestration Tax Credit (Section 45Q), which provides an additional financial incentive for companies. New ideas are being developed, like using CO₂ in building materials (like concrete), but these methods need more research before they can be used on a large scale and before they can provide the same financial benefit as EOR (Van Roijen et al. 2025). Governments' policies and regulations will play an important role in influencing what happens to the CO₂ that gets captured (Burke and Schenuit 2023).

Plastics are mostly made from oil and natural gas, which come from deep underground. When we keep making plastics this way, we take carbon from underground and add more CO₂ pollution to the air (when plastics are made) and add more waste (when plastics are thrown away). But if we use the captured CO₂ instead, we wouldn’t be adding extra carbon to the atmosphere. Some people worry that this doesn’t fix the problem because plastic waste can still be harmful if it’s not recycled or managed properly.

To store CO₂ underground, it is first collected and squeezed into a smaller, supercritical form, which means it acts like both a liquid and a gas. Then, it is sent through pipes to a special storage site. At the storage site, the CO₂ is injected deep underground, usually more than half a mile (800 - 1000 meters) below the surface (Carbon180). It is stored in special rock formations that trap the CO₂ and prevent it from leaking back out. These storage sites must be big enough to hold CO₂ for many years and have the right kind of rocks to keep it underground (Source: From Guidelines for Community Engagement in Carbon Dioxide Capture, Transport, and Storage Projects).

When CO₂ turns into a solid, typically through chemical reactions that convert it into a salt. In this case, "salt" refers to a compound formed when an acid and a base react (baking soda and chalk are examples of this type of salt compound), not the table salt (sodium chloride) we eat. These solid forms of CO₂ can be used in different ways. One common solid form is calcium carbonate (CaCO₃), which can help farmers grow better crops by reducing soil acidity. It is also used in antacid medicine to help with stomach acid. Another way CO₂ is used in solid form is by turning it into rock-like materials to be stored permanently in nature, keeping it out of the atmosphere.

CO₂ can be transported via pipeline, truck, rail, and boat, while underground pipelines (like those used for natural gas) are a more efficient option (Great Plains Institute). These pipelines move the CO₂ from where it is captured to where it will be stored or used.

If the storage site is chosen carefully (e.g. geologists have chosen the rock formation structure that wouldn't collapse easily or leak gas) and managed well (e.g. there are regular monitoring and safety protocols and those are done properly), the CO₂ stays underground permanently and has almost no chance of leaking. Scientists say that more than 99% of the CO₂ will stay underground for at least 100 years, and probably even for thousands of years. (source: Guidelines for Community Engagement in Carbon Dioxide Capture, Transport, and Storage Projects and Carbon180)

CO₂ can leak if there is damage to the pipelines that transport it. One big risk is that cracks in the pipe can spread quickly, causing a large amount of CO₂ to escape all at once. Water inside the pipeline can make the problem worse by creating an acid that eats away at the metal, making the pipes weaker. CO₂ is usually transported as a supercritical fluid, which means it is in a state where it acts like both a liquid and a gas. In this form, CO₂ is denser and easier to move through pipelines. However, safety rules for CO₂ pipelines don’t always cover all the risks, especially when CO₂ is transported as a liquid or gas instead of a supercritical fluid. If pipelines aren’t built and maintained properly, leaks can happen more easily (Pipeline Safety Trust).

If done correctly, storing CO₂ underground should not affect drinking water. However, there are some risks. If the injection wells (the deep holes where CO₂ is stored) are not built properly, or if there are cracks in the surrounding rock, CO₂ could leak and mix with underground water. This could change the water’s quality. To prevent this, experts carefully choose where to store CO₂, monitor the pressure, and track where the CO₂ moves underground. In the U.S., the Environmental Protection Agency (EPA) has strict rules under the Underground Injection Control (UIC) program to make sure underground wells don’t contaminate drinking water (Carbon180).

Solidified carbonates in salty underground areas (called saline deposits) are generally stable and do not react much with their surroundings, meaning they are inert. The U.S. Environmental Protection Agency (EPA) sets standards for drinking water quality to ensure compliance. Before any project is approved, scientists do detailed studies and use computer models to check for risks.

The amount of CO2 produced depends on different things, like:

• How far does the CO2 need to travel from the DAC plant to the storage site
• What kind of energy does the plant use ( electricity from the grid or 100% renewable energy)
• Whether the process needs extra heat to work

A 2021 study found that for every 1 ton of CO2 captured, the amount of CO2 released during the whole process can range from 0.05 tons (very efficient, 95% capture) to 0.91 tons (not very efficient, only 9% capture). This means some DAC plants are much better at removing CO2 than others, depending on how they are designed and powered.

Strong monitoring, verification, and reporting requirements are a good start towards this. However, in order to meaningfully reduce our reliance on fossil fuels, we collectively have no choice but to reduce our consumption of fossil fuels.

Yes, banks could be encouraged to invest in DAC projects. Banks usually invest in projects that make a lot of money, like oil pipelines, because those have clear profits. DAC projects, on the other hand, don’t make as much money yet because there is no U.S. law requiring companies to remove CO₂. That means banks won’t invest unless they see a big financial benefit.

DAC removes CO₂ from the air so it can count as Scope 3 emissions reduction. In theory, DAC can be used to offset Scope 3 emissions for any industry as companies could fund DAC projects and use the captured CO₂ toward their carbon reduction or ESG goals. In practice, relying on DAC alone is neither economically nor environmentally efficient, especially when existing solutions can directly reduce emissions. For example, replacing coal-fired electricity with renewable energy is a more effective way to cut emissions than using DAC to offset coal-related emissions.

It’s uncertain. Right now, the federal government supports DAC through programs like the DAC hubs, but future funding could change. Some of the first DAC hubs are in Red States, bringing jobs and money to those areas, which might help keep funding in place. However, if the administration shifts funding to tax cuts, fewer DAC projects might get money. At the same time, the Trump administration has supported Carbon Capture and Storage (CCS), which could help DAC projects since they both focus on carbon management. Key officials, like Doug Burgum (Department of the Interior), Lee Zeldin (EPA), and Chris Wright (Department of Energy), have spoken in favor of CCS, which might also benefit DAC.

The planning for very many of these DAC facilities is not far enough along to provide a fully informed answer. There are still a lot of open questions about what community-centered agreements will look like, and how we ensure that DAC is deployed in a way that doesn’t negatively impact local resources.

To develop tools and processes for community-centered cumulative impact assessments, it is important to adopt a definition of cumulative risk that includes both chemical and non-chemical stressors. This broader approach recognizes that exposures to pollution often overlap with social stressors such as poverty, poor housing quality, and limited access to healthcare. Early in the assessment process, it is also critical to incorporate environmental and demographic indicators to help identify and prioritize vulnerable communities that may face a disproportionate burden of harm.

One example of a new tool that can support community-centered cumulative impact assessments is the CHIA tool, which stands for Cumulative and Health Impact Assessment. Developed by the U.S. Environmental Protection Agency (EPA) Region 7 team for Resource Conservation and Recovery Act (RCRA) permits in Iowa, CHIA provides a structured desktop review process to identify cumulative environmental and health risks around regulated facilities. The tool combines screening for chemical exposures with broader assessments of environmental quality, public health burdens, and quality of life indicators in nearby communities. CHIA emphasizes early public engagement, systematic cross-program coordination within EPA, and a multi-step evaluation of potential risks before permitting decisions are finalized. It uses a wide range of data sources, including environmental monitoring databases, demographic screening tools like EJSCREEN and CEJST, to create a more complete picture of cumulative impacts on communities. By applying CHIA early in the permitting process, agencies can identify potential risks, prioritize health protections, recommend mitigation measures, and support decisions that avoid compounding existing burdens in already overburdened areas.

Similarly, Health Impact Assessment (HIA) programs, such as those led by The Pew Charitable Trusts and the Centers for Disease Control and Prevention (CDC), offer a model for systematically integrating health considerations into decision-making processes across sectors like housing, transportation, land use, and environmental permitting. An HIA is a structured, evidence-based process that evaluates the potential health effects of a proposed policy, project, or plan, with a strong emphasis on stakeholder and community engagement. Like CHIA, HIAs aim not only to identify risks, but also to recommend practical steps that maximize health benefits and address community priorities. Together, tools like CHIA and the broader practice of HIA show how cumulative risk and health data can guide agencies toward more protective, community-responsive decisions on mitigation measures, permit conditions, and project designs.

Cumulative risk and health data should ultimately guide decisions about mitigation measures, permit conditions, and the exploration of alternative project designs.

Sources: ChemCon Conferences, NEIHS, EPA Regions

Generally, Post-Injection Site Closure, and Emergency, and remedial response plans are included in the UIC Class VI permit application. As a result, the strategies are agreed upon during the permitting process. There are ongoing legislative initiatives addressing these concerns as well. Trust funds are being established that are to be paid on a per tonne of CO2 basis to the state to support future remediation, should it be needed. Many operators are also active in supporting local EMS and providing training exercises where CO2 storage projects are located.

Pipeline and Hazardous Materials Safety Administration (PHMSA)’s investigation revealed several contributing factors to the accident, including but not limited to, Denbury not addressing the risks of geohazards in its plans and procedures, underestimating the potential affected areas that could be impacted by a release in its CO2 dispersion model, and not notifying local responders to advise them of a potential failure (PHMSA).

They are not. WHEJAC released a report calling for the consideration of cumulative impacts, among other policy changes.

As for what a Class 6 well is: the EPA regulates the construction, operation, permitting, and closure of all injection wells. Class 6 specifically covers geologic sequestration wells. It includes requirements like site characterization, an emergency response plan, a monitoring, verification, and assessment plan, and a site closure plan. It can sometimes take up to 2 years for that permit.

The post-injection site care period (the post-operations monitoring time frame) is determined as part of the permitting process. The default standard set by EPA is 50 years - that is, the injecting company is responsible for monitoring the secure storage of CO2 over 50 years. Now, some states have different default monitoring timelines (e.g., 10 years) and the regulating authority can reduce that monitoring timeline if they feel confident that the site has been closed out appropriately and the monitoring program shows no migration (movement) of the injected CO2. Long term, many states have introduced and passed legislation that establishes a state-level trust fund that would handle any future issues that fall outside of this agreed-upon monitoring period.

They are secured in a similar way or manner as typical oil and gas wells. Likely, they are gated, have proper signage, and gate access. Overall, it depends, different communities, regulators, and project developers can take a variety approaches to ensure sites remain undisturbed. For example, there are guidelines for project developers to note in deeds, and other documents typically reviewed during title searches, so future property owners should be aware of the carbon dioxide stored underground.

Yes. Very commonly, DAC business models include both tax credits AND credits from the voluntary credit marketplace. For example, Microsoft is buying credits from the Climeworks plant in Iceland.

There are several different DAC technologies in development, maybe four to six that are seriously being considered. Each has a different emissions profile. Some systems may emit small amounts of ammonia, for example. Ammonia is already found in agriculture, from fertilizers, so it’s not unfamiliar. But it’s also detectable by smell, which means even low levels might be a nuisance in communities. Research is just starting around these potential emissions, this work only really began in the last 3–5 years. Some technologies have very low emissions, but everything comes with trade-offs. For example, a system with less noise might emit more trace chemicals, and vice versa. In the case of CO₂ storage, it is highly regulated. Permits are needed at both the federal and state levels, often requiring extensive proof that the storage is safe, permanent, and trackable. These permits also include financial instruments, long-term monitoring, and community engagement requirements.

Based on this report by the Rhodium Group, a DAC plant with a carbon capture capacity of 1 million metric ton per year (1MMt/year)  can create about 3,428 jobs, according to the Rhodium Group report. These jobs are split into:

• 3,070 jobs (89.55%) for plant investment (construction, engineering, and equipment manufacturing) – These jobs are temporary and mostly happen during the building phase.
• 359 jobs (10.4%) for plant operation and maintenance – These jobs are long-term and more likely to stay local.

The report does not say exactly how many construction jobs stay in the host community. It also does not provide details on how developers plan to hire local workers.

DAC hubs can help local businesses grow by creating opportunities in their supply chain and service networks. Some examples of small businesses that could benefit include:

• Welding and fabrication shops (making steel parts and pipes for DAC plants).

• HVAC and cooling system providers (Maintaining the air filtration systems that DAC technology needs to work properly).
• Chemical suppliers (Providing special materials like sorbents and solvents that help capture CO₂).
• Environmental monitoring firms (Helping DAC facilities track emissions, follow regulations, and build trust with the community).

Furthermore, DAC hubs can introduce broader economic development in the area beyond the sectors closely associated with DAC. With higher income, the local communities would have higher demands for other goods and services, including restaurants and local shops.

Yes, DAC can benefit small businesses and communities, but it requires intentional efforts to connect them to opportunities. For example, in Hipperous, Virginia, small businesses were recruited for offshore wind projects using job fairs, community partnerships, and economic development agencies. Similar efforts could be made for DAC.

The benefit of educating K-12 teachers, students, parents, and other stakeholders from underrepresented communities is that they hold lived experiences that should inform project development and project operations. The DAC industry is still very young, which means that despite a project developer's best intentions, there will be variables that they have yet to consider or prioritize. For DAC to be highly accountable, it must be visible to and well understood by the public.

DAC is a good topic for educating any community about technology deployment and its inevitable tradeoffs.  Any time communities engage in decision-making and guidance at the grassroots level, it is easier to create development scenarios that offer benefits to the breadth of an impacted community.  DAC technology deployment could bring jobs, infrastructure enhancements, and reduce the carbon footprint of a community or region, while also contributing to changes in the landscape (visual, noise, etc.).