An economic model with the capability to analyze sorbent degradation was developed for direct air capture. Sorbent degradation not only leads to higher costs than anticipated, but it can also result in high carbon footprints, especially when carbon-intensive energy sources are used. The capacity fade model can be used to determine the sorbent replacement time that optimizes the performance and cost of DAC systems while also minimizing their environmental impact. The degradation form and rate both influence the carbon footprint, cost, and optimal sorbent replacement time.