Open AccessThis article is
- freely available
The Tenuous Use of Exergy as a Measure of Resource Value or Waste Impact
Environment and Resource Studies, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
* Author to whom correspondence should be addressed.
Received: 5 November 2009; Accepted: 19 December 2009 / Published: 23 December 2009
Abstract: Exergy is a thermodynamic concept that has been widely promoted for assessing and improving sustainability, notably in the characterization of resources and wastes. Despite having many notable benefits, exergy is often misused by authors who tend to apply it as an intrinsic characteristic of an object (i.e., as a static thermodynamic variable). Using both theoretical and empirical evidence the authors present five key limitations that must be overcome before exergy can be applied to characterize objects: (1) the incompatibility between exergy quality and resource quality; (2) the inability of exergy to characterize non work-producing resources via the concentration exergy; (3) the constraints placed on the derivation of exergy; (4) problems with the exergy reference environment; and (5) the multiple perspectives applied to exergy analysis. Until the limitations are addressed, exergy should only be used for its original purpose as a decision making tool for engineering systems analysis.
Keywords: exergy; resource value; waste impact; sustainability assessment
Citations to this Article
Cite This Article
MDPI and ACS Style
Gaudreau, K.; Fraser, R.A.; Murphy, S. The Tenuous Use of Exergy as a Measure of Resource Value or Waste Impact. Sustainability 2009, 1, 1444-1463.
Gaudreau K, Fraser RA, Murphy S. The Tenuous Use of Exergy as a Measure of Resource Value or Waste Impact. Sustainability. 2009; 1(4):1444-1463.
Gaudreau, Kyrke; Fraser, Roydon A.; Murphy, Stephen. 2009. "The Tenuous Use of Exergy as a Measure of Resource Value or Waste Impact." Sustainability 1, no. 4: 1444-1463.