A case study to application of exergy-based indicators to address the sustainability of Bangladesh residential sector

In this paper, energy, exergy, and sustainability analyses are done for the residential sector of Bangladesh based on statistics from 2000 to 2015. The purpose is to gain a deep understanding and pragmatic perception of this sector's energy consumption. It is found that the energy efficiency varies between 25.54% and 37.77% while the exergy efficiency varies between 6.35% and 9.04%. In order to address the sustainability of this sector several indicators such as depletion number, sustainability index, lack of productivity, relative irreversibility, renewable share, non-renewable share, waste exergy ratio, and environmental effect factor are used. Depletion number varies between 0.91 and 0.94 while sustainability index varies between 1.06 and 1.11. The high rate of depletion of fossil fuels has contributed to a lower value of sustainability index. Among various types of fossil fuel consumed in this sector, both energy and exergy from biofuel is higher, and this is validated from high values obtained for the used indicators. For biofuel, the maximum relative irreversibility is found to be 0.83 and maximum lack of productivity is 12.19. To ensure sustainability and to reduce environmental impact from this sector, it is recommended to introduce sustainable cooking technologies in the rural sector.