Article: Development of an exergy diagram for integrated energy systems illustrating the irreversibility along energy paths Journal: International Journal of Exergy (IJEX) 2018 Vol.27 No.4 pp.481 - 499 Abstract: This paper tackles the development of an exergy diagram, adapted from the heat (<i>Q</i>)-Carnot factor (<i>θ</i>) one, where energy quality factors are given in the ordinate axis while energy terms constitute the abscise axis. Energy and exergy balances are then shown and the nature of irreversibility sources (energy loss, energy potential degradation) is revealed, contrary to traditional Grassman diagrams. In this paper, the graphical construction is extended to integrated energy systems where energy paths are differentiated according to renewable and non-renewable sources. Thus, it permits the electricity use, which is really paid, to be emphasised, and the overall behaviour to be better understood. As well, the diagram is developed to illustrate the results of dynamic analyses by considering environment reference state variations. To this aim, the graphical construction has been applied to individual units and then, step by step, to a solar assisted heat pump using ice storage. Inderscience Publishers - linking academia, business and industry through research

Title: Development of an exergy diagram for integrated energy systems illustrating the irreversibility along energy paths

Authors: Etienne Saloux; Mikhail Sorin; Alberto Teyssedou

Addresses: Engineering Physics Department, Nuclear Engineering Institute, Polytechnique Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, Québec, H3T-1J4, Canada ' Department of Mechanical Engineering, Faculty of Engineering, Sherbrooke University, 2500 Boulevard de l'Université, Sherbrooke, Québec, J1K-2R1, Canada ' Engineering Physics Department, Nuclear Engineering Institute, Polytechnique Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, Québec, H3T 1J4, Canada

Abstract: This paper tackles the development of an exergy diagram, adapted from the heat (Q)-Carnot factor (θ) one, where energy quality factors are given in the ordinate axis while energy terms constitute the abscise axis. Energy and exergy balances are then shown and the nature of irreversibility sources (energy loss, energy potential degradation) is revealed, contrary to traditional Grassman diagrams. In this paper, the graphical construction is extended to integrated energy systems where energy paths are differentiated according to renewable and non-renewable sources. Thus, it permits the electricity use, which is really paid, to be emphasised, and the overall behaviour to be better understood. As well, the diagram is developed to illustrate the results of dynamic analyses by considering environment reference state variations. To this aim, the graphical construction has been applied to individual units and then, step by step, to a solar assisted heat pump using ice storage.

Keywords: exergy; exergy diagram; irreversibility; exergy reference environment; solar collectors; heat pump; thermal energy storage.

DOI: 10.1504/IJEX.2018.096013

International Journal of Exergy, 2018 Vol.27 No.4, pp.481 - 499

Received: 22 Dec 2017
Accepted: 07 Aug 2018
Published online: 06 Nov 2018 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article

Title: Development of an exergy diagram for integrated energy systems illustrating the irreversibility along energy paths

Keep up-to-date