The rankings of importance of the input parameters and how these rankings change across the different performance indicators are visualised in Figure . ‡ Figure shows the TVSA Sobol indices for purity, productivity, specific thermal energy, and specific electricity. Whereas Figure shows the same for an S-TVSA process. Firstly, a key observation from Figures is that DAC performance is dictated by both adsorbent and process parameters. This confirms they need synergistic optimisation to develop an optimal DAC process. In a TVSA process, the process parameters that consistently rank high are vacuum pressure and heating temperature. Meanwhile, the adsorbent properties that consistently rank high are the CO2 LDF constant, monolayer H2O uptake, and the CO2 isotherm affinity parameter, whilst the heat transfer coefficient is also crucial for productivity. The material properties consistently ranked in the bottom half are the maximum CO2 capacity isotherm parameter, the density of the pellet, and in all but the specific thermal energy, the heat capacity of the adsorbent. ‡ The scatter plot results of the global sensitivity analysis from every performance indicator for both processes can be found in the ESI Figures . The results of the global sensitivity analysis for working capacity can be found in the ESI Figures S17-S18. Email: jpy1@hw.ac.uk RCCS, Heriot-Watt University