Open AccessThis article is
- freely available
The Characteristics of the Exergy Reference Environment and Its Implications for Sustainability-Based Decision-Making
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: 4 May 2012; in revised form: 25 June 2012 / Accepted: 3 July 2012 / Published: 5 July 2012
Abstract: In the energy realm there is a pressing need to make decisions in a complex world characterized by biophysical limits. Exergy has been promoted as a preferred means of characterizing the impacts of resource consumption and waste production for the purpose of improving decision-making. This paper provides a unique and critical analysis of universal and comprehensive formulations of the chemical exergy reference environment, for the purpose of better understanding how exergy can inform decision-making. Four related insights emerged from the analysis, notably: (1) standard and universal chemical exergy reference environments necessarily encounter internal inconsistencies and even contradictions in their very formulations; (2) these inconsistencies are a result of incompatibility between the exergy reference environment and natural environment, and the desire to model the exergy reference environment after the natural environment so as to maintain analytical relevance; (3) the topics for which exergy is most appropriate as an analytical tool are not well served by comprehensive reference environments, and (4) the inconsistencies point to a need for deeper reflection of whether it is appropriate to adopt a thermodynamic frame of analysis for situations whose relevant characteristics are non-thermodynamic (e.g., to characterize scarcity). The use of comprehensive reference environments may lead to incorrect recommendations and ultimately reduce its appeal for informing decision-making. Exergy may better inform decision-making by returning to process dependent reference states that model specific processes and situations for the purpose of engineering optimization.
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 Characteristics of the Exergy Reference Environment and Its Implications for Sustainability-Based Decision-Making. Energies 2012, 5, 2197-2213.
Gaudreau K, Fraser RA, Murphy S. The Characteristics of the Exergy Reference Environment and Its Implications for Sustainability-Based Decision-Making. Energies. 2012; 5(7):2197-2213.
Gaudreau, Kyrke; Fraser, Roydon A.; Murphy, Stephen. 2012. "The Characteristics of the Exergy Reference Environment and Its Implications for Sustainability-Based Decision-Making." Energies 5, no. 7: 2197-2213.