The solid sorbent direct air capture plant is designed to capture 1 Mt-CO2/year. The sorbent, which is polyamine supported on silica in this analysis, is assumed to be in polymeric structured contactors, and the contactors are installed in the process as modules (Fig. ). The model is agnostic to the geometry of the contactor (i.e., fibers, monolith, laminate) but does consider the sorbent loading inside the contactor (e.g., sorbent to polymer mass fraction), contactor density, module void fraction, module cross-sectional area, module length, and pressure drop. The module size is connected to the blower flow rate and CO2 recovery, and the model uses a solver system to couple these system properties (section S3.C of SI). Direct steaming is used to regenerate the sorbent via condensation of saturated steam on the sorbent. Sorbent replacement refers to only the amine being replaced; this is done via a washing procedure. The silica and contactor lifetime is longer (5 years).