Latent heat thermal energy storage (LHTES) that utilizes latent heat of phase-change materials (PCM) has contributed significant attention towards novel energy storage technologies. To get better thermal conductivity into paraffin wax as base fluid subsequently addition of high conductivity alumina oxide nanomaterial. The addition of nano-alumina (Al₂O₃) particles having 20 nm average sizes with weight concentration respectively, 1,2,3,4 and 5 % in paraffin wax of an LHTES System. The operational parameters are constant flow rate of Heat Transfer Fluid i.e. Reynolds number (Re=1724) and variable temperature i.e. Stefan number (St=0.3050-0.3610) of fluid flowing inside the HTF tube. The concentration of nano-alumina during the charging/discharging in a PCM with LHTES system by weight concentration has been examined. It clearly shows the concert of heat transfer enhancement in presence of nanoparticles with PCM and the role of Stefan number on the thermal routine with LHS system. The remarkable outcome shows, enhancement in pure PCM with addition of less concentration nano-alumina (Al₂O₃) signifies the better charging time period of latent heat storage. The PCM with nanomaterial improves the convective thermal effect for diverse TES system such as, energy storage integrated with buildings, and renewable energy storage systems.