The study presents technical and economic approaches of upscaled laboratory experiment using yard waste (YW) and heterogeneous slurry (HS) to produce heat and power, as a means of bridging the gap between energy production and climate change management strategies. A combination of YW:HS in ratio 2:3 with slurry obtained from a functional digester serving as inoculum was fed into the digester. These were mixed in the ratios of substrates/inoculum/water of 3.5:0.173:6.28 and theoretically upscaled for field-scale biodigesters. The modeled result shows that about 2.5 m3 gas is produced per 5-m3-sized digester over a 30-day hydraulic retention time and estimated project life of 20 years. A business model was adopted for cost recovery of the proposed waste-to-energy system and life cycle cost analysis for the production costs of the seven 5-m3 digesters. Avoided emissions of CO2 from other equivalent energy sources are 4.36 kg, 10.16 kg, 10.37 kg, and 81.32 kg, respectively, for LPG, kerosene, diesel and fuel wood/charcoal. The project is sustainable in for profit, people and planet.
