Water-energy-food nexus of bioethanol in Pakistan: A life cycle approach evaluating footprint indicators and energy performance.

Water, energy, and food are the most basic and essential sectors for human welfare. However, an inextricable nexus and competition exists among these sectors. Production of molasses-based bioethanol is an interesting case resulting in the production of different food and energy materials while consuming water, energy, land, and other raw materials, throughout its life cycle. This paper briefly describes the nexus among water, energy, and food for bioethanol in Pakistan and its environmental implications. A life cycle approach has been used for evaluating four footprint categories including the carbon, ecological, water scarcity, and energy footprints along with an energy analysis of bioethanol. In comparison to conventional gasoline, bioethanol would have benefits in terms of lesser greenhouse gas emissions, better use of productive land, and superior energy performance, but, this will be at the expense of higher impacts in terms of water scarcity. Therefore, considering only a single aspect could result in inadvertent trade-offs that may go unnoticed. The quantified values would help accomplish integrated resource management along with their utilization within limits so as to be available for other uses. This study could help in developing strategies for optimal management of resources to maximize the synergies and minimize the possible trade-offs.