The growing population and economic growth in Central Java causes the consumption of electric energy to increase rapidly even faster than the economic growth itself. So it needs energy conservation program and calculation to predict the amount of electrical energy that must be provided to anticipate the electrical energy crisis in the future. By knowing the estimated growth in electrical energy demand, the amount of electrical energy that must be supplied can also be predicted. In addition, it is necessary to calculate the cost of generating electrical energy, in order to facilitate the needs of the investment. By processing the data released by PLN, Badan Pusat Statistik (BPS) and Dewan Energi Nasional (DEN) using LEAP software, it is found that the projection of electricity demand of Central Java has increased from 20.000 GWh in 2015 to 28.000 GWh year 2025 for all sectors. The supplied electrical energy also increased from 22.000 GWh in 2015 to 31.000 GWh by 2025. Using an optimistic conservation scenario, the demand can be reduced to 20.000 GWh by 2025, in another scenario using a moderate conservation scenario the demand can be reduced to 25.000 GWh by 2025.