Overview
The aim of this study is to evaluate the value of direct air capture and storage (DACCS) in the energy transition (down to the regional level), accounting for key factors, including carbon removal eiciency, timeliness, durability, land footprint and techno-economic performance. The analysis focused on comparing the performance of liquid sorbent direct air capture (L-DAC) and solid sorbent direct air capture (S-DAC). Comparison of DACCS with other mitigation technologies was outside the scope of this study.
Key Messages
- DACCS should not be viewed as a substitute for emissions reduction. The mitigation/abatement of greenhouse gas (GHG) emissions should be the priority, but carbon removal and permanent CO2 storage (e.g. geologically, in cement or concrete but not in synthetic fuels as it would be re-emitted when the fuel is combusted) will still be an essential technology required to address residual emissions.
- Current cost and performance estimates for DACCS vary widely across literature due to inconsistent assumptions about energy supply, plant scale, sorbent degradation, and economic parameters.
- Given that energy supply carbon intensity (CI) is a strong contributing factor in overall value chain emissions, it is critical to incorporate energy supply scenarios based on realistic assumptions and to recognise the related uncertainty.
- Achieving net-negative emissions with DACCS depends primarily on the CI of supplied energy. Both L-DAC and S-DAC with permanent storage can deliver negative emissions today in regions where clean energy is available, or when co-located with renewable energy (RE). Thus, dedicated low-carbon energy supply systems (e.g., stand-alone renewables, geothermal, or CCS-abated fossil) should be actively explored as enablers of early DACCS deployment.
- DAC is relatively expensive but delaying all DACCS deployment until after 2030 may miss critical opportunities to build supply chains, test regulatory frameworks, and reduce costs via learning.
- Scaling DACCS to the gigatonne (Gt) scale requires major investment in manufacturing, workforce, and logistics, especially for modular components like contactors and heat exchangers. Deployment could face bottlenecks in power supply, CO2 transport and storage (T&S) infrastructure, which may delay or limit DACCS’s contribution. Projects also require significant upfront capital investment which can be challenging to acquire, which can contribute further to delays.
- Reducing energy consumption is one of the most effective ways to improve DAC performance across multiple dimensions, including carbon removal efficiency, land footprint, and operating costs (OPEX).
- The report makes several recommendations for further work, such as improving energy supply assumptions, better recognising uncertainty, considering biodiversity impacts, expanding scenarios to include other DACCS technologies and compare them with other carbon dioxide removal (CDR) pathways, and exploring dedicated low CI energy supply systems.
