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, 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 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. 

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 regulation 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). Government 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 the CO2 needs to travel from the DAC plant to the storage site
• What kind of energy the plant uses ( 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.

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 the 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.

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.