DAC (Direct Air Capture) in 2024: Where do we stand?

For the last few decades, Direct Air Capture (DAC) has been promising to solve one of our biggest climate questions: how can we get all that excess CO2 out of the atmosphere? 

It started with an idea; to take a process that normally takes 100,000 years and compress it into just 30 minutes, modeled after one of the most common and complicated carbon sequesters in nature—a tree leaf. Early innovation was pretty small scale, but since then several companies have since emerged with this goal in mind—so where do we stand now?

How does DAC technology work?

Okay, here is where things get a little more complicated. There are two main approaches to DAC tech: Liquid-based methods and solid-based methods. In liquid-based methods , air is bubbled through a liquid solvent  which reacts, forming a carbonate or bicarbonate compound. The CO2-rich solvent is then heated between between 500°F and 1500°F, causing the release of pure CO2 gas which can either be permanently stored underground or used to make new products.

As the name suggests, solid-based methods use solid materials that capture and bind CO2 modules to the surface. When the solid is saturated with CO2 it’s heated at between 32°F and 212°F and exposed to a vacuum, slowly releasing the CO2 where it can be captured and stored. 

There are also a handful of other methods scientists and chemists are experimenting with. One example isCarbon Collect Limited from Ireland who have developed a MechanicalTree™. This Passive Direct Air Capture device uses wind delivered air to capture CO2 in a specially designed chamber where it can be regenerated and recycled. The company says using wind to capture the CO2 massively reduces energy and costs. 

How does DAC help the environment?

If successful, DAC farms could draw massive amounts of excess CO2 from the atmosphere, helping slow global warming and the climate crisis. By capturing CO2 and either storing it safely or using it in products, DAC could be essential for reaching global net-zero emissions targets. Captured CO2 can be stored underground for a long time (a process called carbon sequestration), or could even be used as a raw material in different industrial processes, supporting a more sustainable, circular economy. 

Barriers to DAC

The biggest barrier for rolling out DAC is the price tag. Developing this kind of technology at a scale large enough to have real impact is expensive. Some estimates put the cost from $100 to $600 per ton of CO2 captured. But cost isn’t the only issue – energy is a huge challenge too. 

Capturing, processing, and compressing CO2 requires a ton of energy.  If this energy comes from fossil fuels, it could offset the CO2 captured and reduce the overall climate benefit. To make DAC truly effective, it needs to be powered by renewable energy, keeping the process green and not adding more emissions. However, getting access to those renewables is another barrier to the rollout. 

According to a 2024 University of Oxford study, we need to remove between 7–9 billion tonnes of carbon dioxide annually to hit current climate targets. The Direct Air Capture 2022 IEA report states that DAC will capture more than 85 million tons of CO2 in 2030, growing to 980 million tons CO2 in 2050. Right now though, DAC facilities capture just about 0.01 million tons CO2 per year – so there’s a long way to go

The state of DAC in 2024

As of now, 27 DAC plants have been set up worldwide. Plans for at least 130 large-scale DAC facilities are now in the works, but only three remove more than 1000 tonnes of CO2 per year. Companies like 1PointFive and Carbon Engineering (now Oxy) have big plans to roll out 100 DAC facilities by 2035. Three DAC projects are currently under construction, with two largest expected to start running in 2024 in Iceland (36 kt CO2/year) and in 2025 in the United States (500 kt CO2/year). 

Governments are getting more involved in DAC as part of wider climate strategies. The U.S. is betting big on DAC, with the Department of Energy committing $1.2 billion to develop large-scale DAC hubs across the country. The EU is also backing DAC through its Horizon Europe program, which supports research and innovation in carbon capture technologies. On top of that, DAC is also attracting more and more private investment. In March 2024, California-based climate tech start-up CarbonCapture raised more than $80 million USD from investors that included Amazon and Siemens.

However, while DAC technology has advanced enormously in the last 25 years, it is still in the early stages of commercialization. That being said, the future is looking bright for DAC, if costs can be reduced through innovation, there are more supportive policies to support it, and they can ensure environmental sustainability.