Electricity energy needs increase every year. If the load continues to increase and the supply of electricity is fixed, then one day it will cause the supply to be smaller than the demand. If electricity provider is able to provide electricity in accordance with the growth of expenses, then there will be an increase in the cost of production of the electric power system as well. Electricity production costs are different every hour, because it follows changes in load curve that changes every hour. This study aims to save electricity production costs for 1 day or 24 hours using load shifting methods with pump storage. The general definition of load shifting method is to move the peak load to the base load, so that the cost of generating electricity at peak loads becomes cheaper. Another way to move peak loads to basic loads can use pump storage. Indonesia has new Cisokan Pump Storage located in West Java. The working principle of pump storage is when the base load will act as pump to move water from the lower reservoir to the upper reservoir, and during this process it will consume electricity. When the peak load will act as generator by draining water from the upper reservoir to the lower reservoir, so that it will reduce electricity consumption during peak loads. In this study, two scenarios will be conducted to determine whether load shifting methods using pump storage can save the cost of production of the electrical power system. The first scenario is the operation of 24-hour electric power system without pump storage. The second scenario is the operation of the electrical power system for 24 hours using pump storage. The result of this study, for scenario 1 the total cost of production for 24 hours is $ 20.251.047,78. For scenario 2, the total production cost for 24 hours is $ 20.174.721,5. From scenario 1 and 2, using pump storage as medium to load shifting methods has proven to save 24 hours of electricity power production costs of $ 76.326,28 and electricity prices are also lower in $/kWh every hour.