Evaluating the sustainability of biohydrogen, biogas, and biohythane generation from agricultural, industrial, and municipal waste sources

Abstract

Biofuel production from waste materials offers an effective solution for generating renewable energy in biohydrogen, biogas, and biohythane while reducing waste and recycling valuable nutrients. This review examines recent advances in biohydrogen and biogas production from renewable resources, focusing on the environmental impacts of different production techniques. It emphasizes life cycle analysis (LCA) as an important tool for assessing these impacts and discusses key production pathways and processes. The variability in LCA methodologies – including differences in software, impact categories, system boundaries, functional units, and analytical approaches – poses challenges for direct comparisons of studies. Despite these challenges, fermentation-based production methods show substantial environmental advantages, such as reduced CO₂ emissions, diminished ozone depletion potential, improved human health outcomes, lower ecotoxicity, and reduced fossil fuel use. Combining biohydrogen production with anaerobic digestion for biohythane generation demonstrates even greater energy efficiency and greenhouse gas reduction. Adopting waste-to-energy strategies grounded in life cycle principles could advance renewable energy system implementation and sustainability significantly.