Regional Techno-economic Analysis of Different Solid Sorbent-based Direct Air Capture Configurations

Abstract

Direct air capture (DAC) combined with storage has the potential to deliver carbon dioxide removal (CDR) at scale and will likely play an important role in achieving climate and net-zero targets. The ambient condition of air differs widely across regions with seasonal and daily variations – this can have a major impact on DAC process performance. In this work, we investigate the effect of ambient conditions on two solid sorbent-based DAC configurations: vacuum-pressure temperature swing adsorption (VTSA) and steam-assisted vacuum-pressure temperature swing adsorption (SA-VTSA) and show how they perform in different regions of the world. We found that colder regions where the temperature does not drop below −15°C for a substantial part of the year can provide better process productivity, while drier regions can provide lower energy requirements. Based on the calculated regional DAC process performance and interest rate, the calculated Levelized cost of DAC (LCOD) for the VTSA cycle ranges between $348−603 per tCO2, captured from the air assuming an electricity price of $50 per MWh. Adding a steam purging step was shown to reduce LCOD in all regions by up to 15% in hotter and drier regions.

Keywords: Negative emission technologies (NETs), carbon dioxide removal (CDR), direct air capture (DAC), solid sorbent-based adsorption, techno-economic analysis, cost