Minimizing Electrical Energy Costs for Residential Buildings Based on the Characteristic of Walls

The aim of this research is to compute the electrical energy cost (ECost) for residential buildings. In this study, there are five kinds of characteristics of walls that have been developed to manufacture different buildings. Under numerical optimization, the electrical ECost of residential buildings was calculated considering to wall characteristics and outside temperature. The result of this research described that the electrical ECost of residential buildings-I, II, III, IV and V were: IDR 29,800; IDR 28,700; IDR 27,300; IDR 26,400 and IDR 25,200. In addition, the proposed study only calculated the electrical ECost of the air conditioning during hot days in Barru, South Sulawesi.