The electrical energy demand growth in Ethiopia has been enormous in the past few years asrna result of economic development. This sharp increase in demand is expected to continue inrnthe years to come. Therefore, in the face of increasing demand for electric energy in allrnsectors and the limited generation capacity problem, energy conservation has to be consideredrnat the demand side as one of the major options to achieve a sustainable power supply system.rnNext to the domestic sector, the second most energy consuming sector in Ethiopia is therncommercial sector. Hence, to succeed in reducing energy consumption and in developing arnsustainable energy structure, the buildings in this sector need to consider integratingrnsustainable energy and energy conserving strategies into their design.rnThis thesis work investigates the potentials for energy conservation in the commercialrnbuilding sector of Addis Ababa, Ethiopia. The objective of the study is to identify and suggestrnthe energy conserving design strategies that can reduce energy consumption of a buildingrnbeyond conventional practice, making it more energy efficient and self-sufficient, withrnrespect to its power demand. This is done by selecting best available design concepts andrntechnologies related to energy efficiency and renewable energy resource utilization, whichrncan be implemented for commercial buildings in Addis Ababa. Case studies are carried out onrntwo typical commercial buildings located in the city in order to evaluate the energyrnconsumption of conventional buildings and to select the appropriate energy conservationrnmeasures that can be taken. An energy conserving electrical system is then proposed for theserntwo sample buildings. Annual energy saving analysis is done by comparing the energyrnconsumption of the base case and the proposed case systems. The economical aspect of thernenergy conserving electrical design is also studied through the life time cost analysis.rnRETScreen is used as an evaluation tool in order to demonstrate the application of thernstrategies and to what extent it can make an impact on the energy consumption of thernbuildings. The thesis presents the methodology followed to design the proposed system. Itrnalso discusses the result of the annual energy saving and the life time cost analysis. Finally,rnbased on the result of the work, suggestions are made on strategies that could help to realizernenergy-saving potentials, promote energy conservation, and thereby enhance energyrnsustainability in the nationâ€™s commercial building sector.rnKey words: Energy Conservation, Energy Efficiency, Renewable Energy, CommercialrnBuildings, RETScreen