Assessing rice straw availability and associated carbon footprint for methanol production: A case study in India

The necessity of transitioning to clean energy sources is driving a transformative shift towards the utilisation of biofuels as a promising pathway to achieve a future with net-zero emissions and robust energy security. This global imperative has intensified research into biofuels, with bio-methanol emerging as a highly promising candidate.

This study conclusively demonstrates the feasibility of producing bio-methanol from rice straw residues in rural India, focusing specifically on Assam. Utilising GIS technology, the research accurately mapped rice straw availability and designed an optimised supply network for efficient collection and transportation. The findings revealed substantial rice straw resources in the region, capable of yielding over 1200 tonnes of bio-methanol annually. Furthermore, the associated carbon footprint was significantly lower than that of conventional methanol production.

By evaluating 5480 ha of potential cropland for rice, the study estimated an annual generation of 4411 tonnes of rice straw, translating to an impressive bio-methanol production potential of over 1215 tonnes, or approximately 3.3 tonnes per day. The study calculated the overall carbon footprint to be 421.84 tonnes CO2e per year, equating to just 0.096 kg CO2e per kilogram of rice straw and 0.347 kg CO2e per kilogram of biomethanol, remarkably lower than the footprint of traditional fossil methanol production. The results demonstrate the viability of bio-methanol from rice straw as a sustainable biofuel solution for rural India. Precise biomass assessment, optimised transport networks, and significantly reduced carbon footprint align perfectly with India's clean energy objectives. This robust framework provides policymakers with a powerful tool to harness rural bioenergy, revolutionising the energy landscape and driving sustainable development towards a cleaner future not only in India but in other developing countries as well.

This study provides a compelling foundation for further exploration, asserting that biomethanol when blended with fossil fuels, can enhance energy security, foster a circular bioeconomy, and contribute significantly to net-zero emissions targets.