The influence of the rate of sorbent degradation on carbon footprint and cost is illustrated in Fig. for seven rates of exponential capacity fade. Fig. illustrates the sorbent working capacity as a function of time for the various degradation rates. The rates range from no degradation to none of the initial capacity remaining after 1 year. We again observe an optimum in carbon removal efficiency and carbon footprint when sorbent degradation is included (Fig. ). At higher degradation rates, there is a noteworthy decrease in the carbon removal efficiency (and increase in the carbon footprint) due to the decreasing captured CO2. This increase in energy-related emissions drives the overall carbon removal efficiency down as the sorbent lifetime is extended, approaching a value of 70% (or -0.7 tonne CO2 equiv. per t-CO2 captured) for the higher degradation rates. The levelized cost of capture (LCOC) is shown in Fig. , reported as $ per t-CO2 captured in the left panel (carbon footprint not included) and $ per t-CO2 net in the right panel (carbon footprint included). As expected, increasing the sorbent degradation rate increases the LCOC. Notably, incorporating degradation into the levelized cost of CO2 capture results in an optimum sorbent replacement time that minimizes the DAC process cost. This optimum has not been demonstrated previously for DAC, but it does align with our findings for the BECCS process previously studied, albeit in a slightly different manner without associated revenue from electricity sales. As the sorbent degrades, the rate of CO2 capture decreases, as less CO2 is captured every subsequent cycle, leading to increasing capital and operation and maintenance costs per tonne of captured CO2. However, using the sorbent for longer results in more CO2 captured with that sorbent, reducing sorbent costs as the lifetime increases, regardless of degradation. The increasing capital and O&M costs balance the decreasing sorbent cost at some sorbent lifetime, at which point the sorbent should be replaced. The difference in DAC cost between the lowest and highest degradation rates at the optimum replacement time is approximately $600 per tonne of net CO2 captured.