In photocatalytic (PC) water splitting, a particulate photocatalyst is mixed with water and placed in plastic baggie reactors, which are exposed to sunlight. Action of the photocatalyst leads to production of a H2/O2 mixture, which is separated using pressure swing adsorption to obtain pure hydrogen (see Figure , PC). The CDot/C3N4 photocatalyst reported by Liu et al. is used as a stateof-the-art reference and the plant layout is based on the "type 1 -single bed" design described by Pinaud et al. SI Section 4.1 contains a detailed process description and input parameters can be found in SI Section 6.4.