Biogas Productivity, Financial Analysis, Livestock Mix Pasture Influenced by Biogas Input and Slurry

The research was conducted at the Laboratory of Animal Biology, Animal Husbandry Program, Faculty of Agriculture, University of North Sumatra, in November 2014 to November 2015. This study is a series of studies, the first study was biogas productivity influenced by proportion of goat feces and bagasse as biogas input. The purpose is to determine the productivity of biogas. The design was completely randomized design (CRD) with treatments, T1 (100% feces goat), T2 (75% feces goat + 25% bagasse), T3 (50% feces goat + 50% bagasse), T4 (25% feces goat + 75% bagasse) and T5 (100% bagasse). Parameters were methane production, pH and temperature. The next study was financial analysis of biogas technology utilization with Analysis of Profit and Loss, Revenue Cost Ratio parameters. The series of subsequent research is to determine effects of fermented biogas slurry with various of livestock urine on production and quality of mixed pasture. The design used in the study was Split Plot Design. The treatments consisted of two factors and three replications. Main plot (A): Various of pasture; A1 = Brachiaria decumbens and Stylosanthes guyanenesis; A2 = Brachiaria ruziziensis and Stylosanthes guyanensis. Subplot (B): fermented biogas slurry with various of urine; B0 = Without urine, B1 = With goat urine, B2 = With rabbit urine, B3 = With cattle urine. Parameters observed were fresh weight production, dry weight production, crude protein content and crude fiber content. The result showed that the highest gas production (P0.01) was on T3; i.e. 124.5 liter of CH4 with a pH 7.1, temperature 27.2°C. Financial analysis of the utilization of bio gas technology showed the highest profit is on treatment T3, this is due to bio-gas generated higher than other treatments, the best value of revenue/cost Ratio was on T3 treatment; i.e. 1.90. Application of slurry added with fermented cow urine gives the best result compared to other treatments