Sustainability Assessment of Biodiesel Production in India from Different Edible Oil Crops Using Emergy Analysis

Abstract

The demand for energy has increased gradually over the past few years. As a result, the reserve of petroleum-based fuels is depleting continuously which led to thinking about an alternative energy source. This resulted in the increased popularity of biofuel, which is an alternative and renewable source of energy. This study aims to investigate whether biodiesel production from different edible oil crops is sustainable enough to replace conventional fuels. In this work, emergy analysis has been used to study the sustainability of edible oil crops-based biodiesel production. Wheat germ, groundnut and cottonseed oils produced from edible oil crops have been considered in the present study. Based on the data availability, the study area considered in the present work is the state of Maharashtra, India. Three different processes of biodiesel production have been studied in this work, namely alkali-catalysed, acid-catalysed and lipase-catalysed transesterification processes. The emergy performance indicators such as emergy sustainability index (ESI), emergy investment ratio (EIR), emergy renewability (%R), emergy yield ratio (EYR), environmental loading ratio (ELR) and environmental impact ratio (EVR) are then evaluated for each of the considered biodiesels derived from edible oil crops. The sustainability of the considered biodiesels is then evaluated based on a comparative assessment considering these emergy performance indicators. Based on the emergy analysis, it is found that irrespective of the transesterification processes considered, the wheat germ oil is found to be the most preferable edible oil for the production of biodiesel as it has lowest transformity value. On the contrary, cottonseed oil is the least preferred edible oil as it has the highest transformity value. Similarly, based on the values of emergy indices, it is observed that irrespective of the transesterification processes considered, the biodiesel derived from cottonseed oil crop is found to be the most sustainable followed by biodiesel derived from groundnut oil crop and the biodiesel derived from wheat germ oil crop is found to be least sustainable.