Sustainable bio-energy production models for eradicating open field burning of paddy straw in Punjab, India

The mechanized harvesting of paddy crop has led into open field burning of paddy straw. Burning of million tonnes of paddy straw releases huge potent greenhouse gases which creates perturbations to regional atmospheric chemistry. This paper presents a case study on utilization of paddy straw for power generation through biomethane and bioethanol production on commercial scale and improved biomass cookstove on domestic scale. Three scenario (biomethane, bioethanol and pellet for improved biomass cookstove) have been compared for their energy economics and emission. It has been revealed that if paddy straw is not being burned, it can be effectively utilized for biomethanation and bioethanol production which can yield energy equivalent of 8.0 GJ/tonne and 5.6 GJ/tonne, respectively, while pelletized paddy straw can be used in improved biomass cookstoves to meet out thermal cooking energy requirement with reduced indoor air pollution. The analysis further revealed that biomethanation of paddy straw reduces net global warming potential by 2750 CO₂e kg emissions/tonne. However, bioethanol production showed net global warming potential reduction of 2549 CO₂e kg emissions/tonne. The pelletization of paddy straw for improved cookstove showed net global warming potential reduction of 2459 CO₂e kg emissions/tonne. - Highlights: • Biomethane production from paddy straw showed a total energy yield of 8.0 GJ/tonne. • Bioethanol production from paddy straw showed a total energy yield of 5.6 GJ/tonne. • Biomethanation route showed net global warming potential reduction of 2750 CO₂e kg emissions/tonne. • Pelletization for improved cookstove showed net global warming potential reduction of 2459 CO₂e kg emissions/tonne. • Bioethanol route showed net global warming potential reduction of 2549 CO₂e kg emissions/tonne.