The energy crisis in the future will be a threat for human life. Many advancements of technology currently focus on creating something that perform better than its predecessor but consuming less power. Light-emitting diode (LED) lighting technology has been introduced as a breakthrough of technology which possesses big advantages rather than other lighting technologies. LED lighting technology is able to produce a high luminous flux with very low power consumption, and also lasts longer than others. By consuming lower power, hence the amount of energy being consumed in order to generate the same amount of light will be reduced, and hence, energy saving will happen. This study discusses the replacement analysis of lighting at classrooms at Engineering Center of Faculty of Engineering Universitas Indonesia. The analysis is in terms of illuminance aspect, power quality performance and cost, and it is done by replacing the existing compact fluorescence lamps (CFL) with three different options of LED lamp exist in the market with competitive price. The study suggests that using LED lamp as a replacement for CFL at classrooms at designated room is more efficient; consuming less energy by 42.86%, and moreover saving the electricity cost as well, from IDR 864,360 annually to IDR 493,920.