Exergy as a potential tool for sustainable drying systems

Drying systems are examined from the perspectives of energy, exergy, environmental impact, sustainability and economics, with a focus on how they can help make drying systems more sustainable. Reductions possible through exergy analysis in energy use and environmental emissions and increase in sustainability are discussed in detail and highlighted with a case study. It is demonstrated with the case study that exergy efficiencies normally are lower than energy efficiencies due to exergy destructions and losses. The importance of using exergy analysis to obtain more realistic and meaningful assessments than are obtained with energy analysis of the efficiency and performance of drying systems is demonstrated. The results indicate that exergy can play a significant role in achieving more efficient, environmentally benign, sustainable and economic energy use in drying systems. (C) 2011 Elsevier B.V. All rights reserved.