Mahi Chitale
Independent Researcher
India
Abstract
Life cycle assessment (LCA) offers a comprehensive framework for evaluating environmental impacts associated with all stages of a product’s life from cradle to grave. This manuscript presents a comparative LCA of biofuel and fossil fuel systems, focusing on energy balance, greenhouse gas (GHG) emissions, and other environmental metrics. The study aligns with engineering practices and technologies available up to 2015, using standardized LCA methodology and statistical analysis to ensure rigor and reproducibility. Primary data were sourced from peer-reviewed literature and industry reports published through 2015. The analysis incorporates a statistical comparison table to highlight key differences, formulates five research questions, and identifies research gaps for future investigation. Methodology includes system boundary definition, inventory analysis, impact assessment using midpoint indicators, and sensitivity analysis. Results demonstrate that, under best-practice scenarios, certain biofuels can reduce GHG emissions by up to 60 % compared to conventional diesel, though energy return on investment varies widely across feedstocks. Conclusions underscore the need for region-specific assessments and improved agricultural practices to optimize environmental benefits.
Keywords
Life cycle assessment; Biofuel systems; Fossil fuel systems; Greenhouse gas emissions; Energy balance
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