Ethiopia is experiencing shortage of electric power that is likely to be decreasing day to day, and which tends to use renewable energy resources to execute energy crisis. Tiret is one of the endowment companies in Ethiopia which includes 20 different companies. My research area selected among those Tiret company is TZA dairy Farm and Milk Processing Factory. In this work presents the design and economic analysis of Solar/Biomass electric power generation to replace the existing power supply utility for TZA dairy farm and milk processing factory by investigating solar and biomass potentials on the desired site. The result of thesis was obtained by using MATLAB Simulink, AutoCAD and Microsoft Excel software. For this company currently, the required amount of generated power for supplying the load is around 250KW. The total annual bill of electric power consumption of the company for 250kw power demand is 5,291,123.62 Et.Birr and within four years the total electric power consumption bill cost becomes 21,164,494.48 Et.Birr. The construction cost of solar/biogas hybrid power generation system is 21,179,395.71 Et.Birr. The company’s payback period is around 4 years and the project life time is 20 years. Generally, the company will get sixteen years profit after the payback period is completed within four years.