Biogas as a sustainable and viable alternative fuel for diesel engines: A comprehensive review of production, purification, economic analysis and performance evaluation

Economic and environmental concerns have propelled alternative fuel research in the last few decades. Numerous research initiatives have been undertaken to optimize energy demand by exploring alternative fuels. This comprehensive review presents an in-depth analysis of the current and future prospects of biogas production, filtration and engine applications. To evaluate the performance and emission characteristics of biogas in compression ignition engines, its impact has been extensively analyzed. The study finds that using biogas as an alternate fuel in a dual-fuel mode engine leads to a degradation of 5–27% in performance parameters such as brake thermal efficiency, while brake-specific fuel consumption increases by up to 33%. A subsequent study of emissions reveals a 25–65% reduction in nitrogen oxides and smoke emissions. In contrast, the dual-fuel engine showed a 31% increase in hydrocarbon and carbon monoxide emissions when compared to a conventional diesel engine. In conclusion, biogas has emerged as a promising alternative fuel for diesel engines due to its sustainable nature and potential for reducing emissions. While there are certain trades-offs in terms of performance parameters, the reduction in harmful emissions makes it a viable option for future research and development.