Barium zirconium sulfide (BaZrS3), a chalcogenide perovskite, is attracting a lot of attention for thin-film photovoltaic (PV) application. Unlike the lead halide perovskites, it is stable and does not contain toxic elements. Herein, PV devices incorporating barium zirconium sulfide (BZS) are investigated numerically as a photoabsorber with a back-contact layer of both crystalline and amorphous p+ type silicon, using a Solar Cell Capacitance Simulator software-1D. The titanium (Ti) alloyed BZS, which has an electron-energy bandgap close to optimum for a single junction PV device, is also investigated. A systematic study is carried out by varying the thickness, doping density, and defect density in the BZS layer. Among the two phases of Si, the amorphous one results in higher photoconversion efficiency (PCE) due to a favorable energy band alignment with BZS. The corresponding best PCEs predicted from the study are 19.7% for BZS films and 30% for Ba(Zr0.95Ti0.05)S3 films with the amorphous Si as back-contact.