Evaluating bioenergy pathways for sustainable rice straw utilization in Malaysia: A life cycle perspective

• Rice straw bioenergy pathways were evaluated using a harmonised cradle-to-gate LCA. • A feedstock-oriented functional unit enables consistent pathway comparison. • Pyrolysis shows the lowest environmental burdens among assessed technologies. • Fermentation exhibits the highest impacts, driven mainly by enzyme production. • Replacing open burning with valorisation pathways improves environmental performance. The urgent demand for sustainable energy has highlighted rice straw as a promising renewable feedstock for bioenergy. This study evaluates five technology pathways; combustion, gasification, pyrolysis, anaerobic digestion, and fermentation, using life cycle assessment (ReCiPe 2016, SimaPro v9.5.0.2). A cradle-to-gate boundary with a functional unit of 1 metric ton dry rice straw was applied. Results show fermentation has the highest environmental impacts, largely from enzyme production (35–97% across categories), while pyrolysis yields the lowest impacts due to reduced resource use and absence of high-temperature combustion. The avoided global warming potential from open burning reduction follows pyrolysis > anaerobic digestion > combustion > gasification > fermentation. Sensitivity analysis confirmed robustness and key influencing parameters. A conceptual framework was developed, highlighting success factors and recommendations for rice straw valorization in Malaysia. The study provides guidance for policymakers and industry in identifying sustainable bioenergy pathways, advancing cleaner energy transition.