AUTHOR=Li Xiaolu , Wu Tong , Lin Shunfu 

TITLE=Flexible and optimized operation of integrated energy systems based on exergy analysis and pipeline dynamic characteristics

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 11 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2023.1203720

DOI=10.3389/fenrg.2023.1203720

ISSN=2296-598X

ABSTRACT=Given the energy crisis and severe environmental pollution, improving the energy utilization efficiency of integrated energy systems is crucial. Most existing studies on the optimal operation of IESs are based on the first law of thermodynamics, without considering energy quality and direction attributes. The obtained strategies generally fail to accurately reflect the difference in energy quality.Based on the second law of thermodynamics, this article first analyzes the energy quality coefficients of energy in different forms were analyzed, and the exergy flow was expressed as the product of the energy quality coefficients and energy flow. An exergy analysis model of the electric-gas-thermal integrated energy system was also established based on energy network theory. Secondly, Modeling and analyzing the dynamic characteristics of gas-thermal networks and the corresponding energy storage capacity were explored. Considering the dynamic characteristics of the gas-thermal pipeline network, the useful energy stored in the pipelines was analyzed based on the energy quality coefficients of natural gas and thermal, and the flexibility capacity of each subsystem was also analyzed in combination with the operation of units. Simulation analysis was then conducted on the electric-gasthermal IES 39-20-6 system. The results demonstrated that, from an energy perspective, the loss in the coupling equipment only accounts for 29.05% of the total energy losses, while from an exergy perspective, its proportion is as high as 46.47%. Besides, under exergy analysis, when the dynamic characteristics of the gas-thermal pipeline network are taken into account, wind curtailment rates of the system decrease from 11.22% to 8.27%.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.13 Author Contributions XL, TW, and SL contributed to the conceptualization. XL and TW built the model. TW was responsible for the software. XL and TW visualized the results and wrote the original draft of the manuscript. XL and TW reviewed and edited the manuscript. XL supervised the research and managed the project. Access to funding was provided by XL and SL. All authors have read and agreed to the published version of the manuscript.