This paper investigated, using 1-D analysis, the effect of low energy electrons emitted from Promethium – 147 (Pm-147) on the performance of a silicon PV cell. The Pm-147 source is chosen due to the penetration depth of beta particles with the average kinetic energy of 62.5 KeV emitted from Pm-147, because at this depth the are able to generate charge carriers right down to the base. The continuity equation of excess minority carrier is solved respectively in the emitter for excess holes and in the base for excess electrons. The analytical expression of the density of electrons and holes for each part of the solar cell is derived and, in turn, the electrical parameters (Jsc, Voc, FF, η) of the PV cell are found. The influence of radiation flux on short-circuit current density (Jsc), Open circuit voltage (Voc), fill factor (FF) and conversion efficiency (η) are discussed. if we vary the flux of incident particles up to the value of 3.1010 cm-2, we achieve a relative increase in the PV Cell conversion efficiency of the order of 0.2743 %.