Thermodynamic comparison and dynamic simulation of direct and indirect solar organic Rankine cycle systems with PCM storage

Alvi, Jahan Zeb; Imran, Muhammad; Pei, Gang; Li, Jing; Gao, Guangtao; Alvi, Junaid

Abstract

A thermodynamic comparison between a novel direct solar ORC system (DSOS) and indirect solar ORC system (ISOS) is carried out in this study. A phase change material (PCM) heat storage unit is integrated with both systems to ensure the stability of power generation. Water and R245fa are selected as a heat transfer fluids (HTFs) for ISOS and DSOS respectively. However, R245fa is used as working fluid for both systems. Weekly, monthly and annual dynamic simulations are carried out to compare the performance of both systems using hourly weather data of Islamabad, Pakistan. ISOS has shown 1.71% system efficiency and able to provide 34.02 kW/day power while DSOS has shown 4.5 times higher system efficiency and 2.8 times higher power on annual basis. Numerical model for the PCM storage is developed and validated with the previous experimental data. Average annual amount of energy stored by PCM during charging phase for ISOS is 4.24 MW/day higher than DSOS. However, in comparison with ISOS, DSOS has delivered 33.80 kW/day more power to HTF during discharging phase of the PCM on annual basis. Maximum benefits of PCM storage are observed during the summer season compared to the winter season at selected operating conditions. Furthermore, average annual increment in capacity factor by using PCM storage are found to be 21.71% and 17% for DSOS and ISOS respectively.

Citation

Alvi, J. Z., Imran, M., Pei, G., Li, J., Gao, G., & Alvi, J. Thermodynamic comparison and dynamic simulation of direct and indirect solar organic Rankine cycle systems with PCM storage. Presented at 4th International Seminar on ORC Power Systems, Milan, Italy

• Presentation Conference Type: Conference Paper (published)
• Conference Name: 4th International Seminar on ORC Power Systems
• Acceptance Date: Jan 3, 2017
• Online Publication Date: Sep 12, 2017
• Publication Date: 2017-09
• Deposit Date: Mar 24, 2022
• Publicly Available Date: Mar 30, 2022
• Journal: Energy Procedia
• Print ISSN: 1876-6102
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 129
• Pages: 716-723
• DOI: https://doi.org/10.1016/j.egypro.2017.09.103
• Keywords: ISOS; DSOS; PCM storage; Capacity factor
• Public URL: https://hull-repository.worktribe.com/output/3602602