Optimizing the Volume of Starter and the Time of Fermentation in the Production of Biogas from Vegetable Wastes with Maximum Content of Methane Gas

National energy deposit is only available for the next 23 years. This matter is getting worse with the availability of annual waste production as the impact of rapid rate of population which is around 1.49 % per year. To cope with both matters, waste can be utilized as energy resources through fermentation technology. The urban waste dominated by organic waste like vegetable is potentially produce able to be biogas. The worst utilization of natural starter and the time spent for fermentation are among the existing obstacles to develop energy resources in urban areas. For this purpose, research was carried out to optimize ratio of urban waste, feces and water combined with the time for fermentation. The research employed experimental method with completely randomized design (CRD) of two—factor pattern. The factors are ratio of waste, feces, water and the time for fermentation that consists of 3, 6, 9, 12, 15, 18, 21, 24, and 27 days. The research indicated that optimum proportion to produce maximum biogas volume is 500: 200: 300 for waste, feces, and water respectively. Additionally, three-day fermentation produced the highest volume of biogas.