A study on exergetic efficiency vis-à-vis sustainability of industrial sector in Bangladesh

Industrial sustainability has gained huge attention in the scientific community owing to the concern of global warming. Establishing sustainability indicators by the application of exergy analysis can guide and motivate industrial sustainability. In this context, an attempt is made to establish sustainability indicators for the industrial sector. Different measures to improve the sustainability of the industrial sector of Bangladesh are also discussed. Based on the energy consumption data from the year 2000–2015, energy, exergy, and sustainability analyses are performed. It is found that the energy efficiency varies from 55.01% to 59.67% and exergy efficiency varies from 53.11% to 56.97%. Exergy efficiency is found to be at lower side due to the accounting of irreversibility. Various sustainability indicators such as sustainability index, depletion number, exergetic renewable share, cumulative exergy loss, and non-renewable exergetic share have been studied as well. It is observed that depletion numbers vary from 43% to 45% and the sustainability index varies from 2.21 to 2.32. Non-renewable exergetic share is as high as 98% and maximum cumulative exergy loss is found to be 217.3 PJ in 2015. Improvement potential shows a continuous increase from 22.75% in 2000 to 101.89% in 2015. Waste heat recovery, energy audit, waste minimization, and adopting renewable energy sources are recommended to increase the efficiency and sustainability of this sector. The outcome of this study reveals that exergy analysis is an effective technique to develop energy conservation policies for this sector.