Energy, exergy, and sustainability analyses of the agricultural sector in Bangladesh

Globally, the agriculture sector consumes a considerable portion of energy. Optimizing energy consumption and energy loss from different fuel-based types of machinery will increase the energy sustainability of this sector. Exergy analysis is a useful optimizing method that applies the thermodynamic approach to minimize energy loss. The main goal of this study is to highlight the impact of exergy loss on the energy sustainability of the agriculture sector. Hence, this study focuses on the implementation of exergy-based sustainability parameters to determine the sustainability of the agricultural sector in Bangladesh. A comprehensive analysis combining energy, exergy, and sustainability indicators was conducted based on the data obtained from 1990 to 2017. Overall energy and exergy efficiencies varied between 29.86% and 36.68% and 28.2% and 35.4%, respectively, whereas the sustainability index varied between 1.39 and 1.54. The values of relative irreversibility and lack of productivity indices from diesel fuel are higher than that of other fuel types. Maximum relative irreversibility is 0.95, whereas maximum lack of productivity is 2.50. The environmental effect factor of diesel fuel is the highest (2.47) among all the analyzed fuel types. Replacing old farming devices and selecting appropriate farming methods, appliances, and control systems will reduce exergy loss in this sector.