Optimization of the thermal storage system in a solar-driven refrigeration system equipped with an adjustable jet-ejector

• Published in: Journal of energy storage 2022-01, Vol.45, p.103495, Article 103495
• Main Authors: Luján, José Manuel, Galindo, José, Dolz, Vicente, Ponce-Mora, Alberto
• Format: Article
• Language: English
• Subjects: Adjustable jet-ejector; Dynamic behavior; Hot thermal storage system; Solar refrigeration; System sizing; Thermal management
• ISSN: 2352-152X; 2352-1538
• DOI: 10.1016/j.est.2021.103495

•The optimum dynamic response of a solar refrigeration system with a storage tank is studied.•The refrigeration capacity and COP are assessed for different tank capacities.•The thermal storage tank size is not the most decisive design parameter.•The thermal power consumed from the thermal storage tank is crucial.•For a PTC span of 7.1 m, 13.3 kW of thermal power consumption is found to be optimum. The present paper shows a numerical research about the influence of different thermal storage capacities and thermal power consumption strategies in a solar-driven air-conditioning system operating with refrigerant R1234yf. The computational model is fed with hourly climatic data (solar irradiance and ambient temperature) of the typical meteorological year of a Mediterranean location. A special focus is put on the dynamic response of the refrigeration system, the solar collector, and the sensible heat storage tank. Since the refrigeration needs are nearly synchronized with the sunny hours, small tank volumes are the most convenient architecture to achieve a rapid heating-up after tank discharges. For a parabolic trough collector span of 7.1 m, 13.3 kW of thermal power consumption represents a reasonable trade-off between the main performance indicators, mainly, the refrigeration capacity, COPth (thermal coefficient of performance) and the system's capability to operate properly ensuring an adequate thermal level in the heat reservoir.