Exergetic, Economic and Exergo-Environmental Analysis of Bottoming Power Cycles Operating with CO 2 -Based Binary Mixture


This study focused on investigating the bottoming power cycles operating with CO2-based binary mixture, taking into account exergetic, economic and exergo-environmental impact indices. The main intent is to assess the benefits of employing a CO2-based mixture working fluid in closed Brayton bottoming power cycles in comparison with pure CO2 working fluid. Firstly, selection criteria for the choice of suitable additive compound for CO2-based binary mixture is delineated and the composition of the binary mixture is decided based on required cycle minimum temperature. The decided CO2-C7H8 binary mixture with a 0.9 mole fraction of CO2 is analyzed in two cycle configurations: Simple regenerative cycle (SRC) and Partial heating cycle (PHC). Comparative analysis among two configurations with selected working fluid are carried out. Thermodynamic analyses at varying cycle pressure ratio shows that cycle with CO2-C7H8 mixture shows maximum power output and exergy efficiency at rather higher cycle pressure ratio compared to pure CO2 power cycles. PHC with CO2-C7H8 mixture shows 28.68% increment in exergy efficiency with the levelized cost of electricity (LCOE) 21.62% higher than pure CO2 PHC. Whereas, SRC with CO2-C7H8 mixture shows 25.17% increment in exergy efficiency with LCOE 57.14% higher than pure CO2 SRC. Besides showing lower economic value, cycles with a CO2-C7H8 mixture saves larger CO2 emissions and also shows greater exergo-environmental impact improvement and plant sustainability index.

Publication DOI: https://doi.org/10.3390/en13195080
Divisions: College of Engineering & Physical Sciences > School of Engineering and Technology > Mechanical, Biomedical & Design
College of Engineering & Physical Sciences
Additional Information: © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
Uncontrolled Keywords: Bottoming power cycles,CO -based binary mixture,CO emissions savings,Exergetic analysis,Exergo-environmental impact indices,Sustainability index,Renewable Energy, Sustainability and the Environment,Energy Engineering and Power Technology,Energy (miscellaneous),Control and Optimization,Electrical and Electronic Engineering
Publication ISSN: 1996-1073
Full Text Link:
Related URLs: https://www.mdp ... 1073/13/19/5080 (Publisher URL)
http://www.scop ... tnerID=8YFLogxK (Scopus URL)
PURE Output Type: Article
Published Date: 2020-09-29
Accepted Date: 2020-09-26
Authors: Haroon, Muhammad
Sheikh, Nadeem Ahmed
Ayub, Abubakr
Tariq, Rasikh
Sher, Farooq
Baheta, Aklilu Tesfamichael
Imran, Muhammad (ORCID Profile 0000-0002-3057-1301)



Version: Published Version

License: Creative Commons Attribution

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