Direct Air Capture has grown in importance as a prospective mitigation technology and an option for providing a renewable and sustainable carbon feedstock. However, there are very large engineering and commercial hurdle to its successful deployment.  I will present an update on its current status and highlight future developments and provide a perspective on its place in the future.

AspiraDAC is an Australian DAC technology provider, that proudly leads the global charge with the world's pioneering solar-powered Direct Air Capture (DAC) system. At its core, AspiraDAC is distinguished by cutting-edge innovations, prominently featuring advanced metal-organic framework (MOF) nanomaterials and a specialized modular DAC design. 

 

The specially designed DAC modular units include an innovative energy solution, to minimise the amount of energy required to capture a specific amount of carbon dioxide.  It is the only DAC solution to integrate the energy supply with the capture technology.  Being modular, its pathway to scale is via large scale manufacture, leveraging the cost reduction strategies of industries such as solar pv and automotive.

 

Noteworthy is AspiraDAC's integration of innovation, renewable energy utilization, and environmental stewardship, offering a holistic approach to the global imperative of carbon reduction in the face of climate change. The presentation will provide summary of AspiraDAC technology and its journey in creating an Australian native DAC technology to solve climate change.  AspiraDAC's strides towards DAC with permanent geological storage of captured CO2 exemplify not only a great example of Australian CCUS solutions but also reinforce Australia's pivotal role in shaping a greener and more sustainable future.  

Direct air capture is now considered an essential part of the portfolio of technologies that can enable us to limit global warming to acceptable levels. Apart from geological storage of the product CO₂, it can also be used for the manufacturing of carbon neutral chemicals. CO₂-capture from air is challenging because the low CO₂ concentration requires huge amounts of air to be moved through the contactors and the thermal release of CO₂ from the capture agents will require significant amounts of energy.

 

Here we provide a technical development roadmap by which liquid-absorbent based CO₂-capture processes, the leading technology in CO₂-capture, can be used for air capture. This is advantageous as one can build upon the existing and standard design and engineering practices, which will facilitate development and deployment. The technical roadmap is based on the following staged approach:

This approach reveals that CO₂-capture costs below $100/t CO₂ are achievable.

The outcome of the technical roadmap is used for an estimate of costs to produce methane from CO₂ and H₂, which results in a renewable fuel that could be exported using the existing infrastructure that can compete with export of liquid hydrogen.

Direct Air Capture (DAC), a groundbreaking concept in the realm of climate solutions, has emerged as a pivotal avenue for achieving negative emissions. By directly extracting CO₂ from ambient air, DAC offers a unique advantage by addressing the root cause of increasing atmospheric CO₂ levels. Among DAC methodologies, the adsorption-desorption process utilizing solid adsorbents presents notable promise. However, the large heat of adsorption requires high energy consumption for regeneration of adsorbents, significantly compromising the economic viability and productivity of DAC. 

Here, we show a vapor promoted DAC process to recover the adsorbed CO₂ by in situ vapor purge using water harvested from atmosphere synergistically. The desorption of CO₂ is substantially enhanced in the presence of concentrated water vapors at around 100 °C, resulting in the concurrent production of 97.7% purity CO₂ and fresh water without the use of vacuum pumps. Moreover, we demonstrate a prototype of this DAC powered by sunlight, which recovers 98% of the adsorbed CO₂, the highest among all other DAC technologies, and consumes 20% less thermal energy. 

In another case when 10 kPa vacuum is applied, this in situ vapor purge can achieve near complete regeneration of the chemisorbents at temperatures as low as 60 °C, producing 99% purity CO₂ with a stable working capacity of 1.10-1.13 mmol/g for 45 cycles. The minimum work required for regeneration was only 1.62 MJ/kgCO₂, over 37% lower than temperature-vacuum swing desorption. This low-temperature regeneration process not only reduces the energy demand but also reduces the overall cost of DAC.

People in this sector tend to talk in acronyms and assume the audience knows what they are talking about. I used three in my very short title. No wonder peoples’ eyes sometimes glaze over when talking about this subject. I hope to provide clarity and insight into this sometimes complex and evolving space.

 

I aim to highlight how Direct Air Capture (DAC) is being supported in the Voluntary Carbon Market (VCM) through Standards and Registries, such as Puro.earth and Puro’s CO2 Removal Certificates (CORCs). 

 

This presentation aims to highlight an overview of global initiatives supporting DAC while providing a vision for the future of the DAC industry in Australia.