Anaerobic Digestion (AD) Based Waste Management in Nepal: Technologies and Implementation Modalities

Developing countries are still facing severe challenges for providing access to clean energy, managing waste and struggling to meet Sustainable Development Goals (SDG) targets. Anaerobic Digestion (AD) based waste management technologies have great potential for addressing these challenges. Public Private Partnerships (PPP) are the key government's policy and strategic directions for promoting biogas as a multi-beneficiary's product and services in Nepal. Nepal's biogas promotion PPP model and technologies in domestic biogas sector have been replicated in many African and Asian countries. AD based Gobar Gas Company (GGC 2047 model) and Continuously Stirred Tank Reactor (CSTR) based technologies have been promoted for domestic and large applications respectively in wider scale. Comprehensive review and analysis using technological and implementation progress results through government interventions revealed that with the potential of 1.1 million of domestic biogas 433,173 systems have been installed. Quantification of outcomes of AD based technologies revealed that in addition to the energy access to more than 1.8 million people, these significantly contributed for production of gas amounting 456,282 m3 and substituted equivalent 15,578 nos. of LPG cylinders and 2229.91 tons of fertilizer daily. Under Carbon Development Mechanism (CDM), Total 21.20 million USD have been earned as carbon revenue from this sector, which has played significant role for earning revenue from carbon financing. Similarly, Developing Carbon Program for Large Scale Biogas through ITMO (Internationally Transferred Mitigation Outcomes: a new carbon mechanism) is under way. Overall, biogas sector is contributing for country' s energy security and circular economy through replacement of fossil fuels and chemical fertilizers along with the waste management.