Double perovskite, Cs2AgBiBr6, is introduced as a lead-free perovskite solar cell. Device modeling of Cs2AgBiBr6 (DP) was accomplished to obtain the optimum parameters using the Solar Cell Capacitance Simulator (SCAPS). Two devices with two different hole transport layers (HTLs) were investigated, including P3HT and Cu2O. Please see manuscript .pdf for full abstract.