Advancing bioethanol: exploring feedstock diversity, production pathways, and environmental implications

Abstract

The depletion of finite fossil fuel reserves, coupled with the ever-growing global demand for energy, has raised significant concerns about the long-term sustainability of fossil fuel consumption. As these conventional energy sources become increasingly scarce, the need for viable alternatives has become more urgent. This pressing challenge has driven researchers, policymakers, and industries to explore and develop sustainable energy solutions that can reduce dependence on fossil fuels. Bioethanol, a sustainable substitute for gasoline, is produced globally, supporting economic growth in both developed and developing nations. It is derived from a wide range of feedstocks, including industrial waste and by-products like steel mill gases and glycerol from biodiesel production. Different bioethanol generations vary in technological readiness and environmental impacts, assessed using Life Cycle Assessment (LCA). This review explores the environmental consequences of different bioethanol production pathways, with a focus on advances in biotechnological methods. It also highlights the potential of lignin-rich biomass, which has been challenging to process but offers significant promise. The review underscores the importance of transparency in biorefinery LCA to fully understand the various environmental impacts. Additionally, it examines the role of genetic engineering, enzyme technologies, and government policies in promoting sustainable bioethanol production. Integrating bioethanol production with green chemistry and circular economy principles can strengthen its position in the bioeconomy, delivering long-term benefits to both the biofuel sector and society at large.