Hybrid storage designs for continuous operation of solar-powered LiBr-water absorption air-conditioning

Abstract

SUMMARYThe design of the energy storage serving solar-powered LiBr-water absorption air-conditioning systems to meet 24-h a day operation is an important parameter that determines the performance of the system and optimizes its components. Introducing hybrid storage designs can improve system performance, reduce collector size, lower storage tank capacity, and hence make 24-h a day operating solar-powered LiBr-water absorption air-conditioning systems more feasible. Moreover, hybrid storage designs will ensure uninterrupted operation in case of maintenance for one of the storage tanks. This paper investigates four hybrid storage designs (heat and refrigerant storage, cold and refrigerant stfsorage, heat and cold storage, and heat, cold, and refrigerant storage) for a continuous operation (24 h a day) of solar-powered LiBr-water absorption air-conditioning. The study includes system description, features, and selection analysis for a constant cooling load of 5 kW in a typical family house in Dhahran City, Saudi Arabia. The results indicate that the hybrid cold and refrigerant storage system is the most suitable design for 24-h a day supply of the cooling effect.

Thermo‐economic optimization and comparison study of LiBr‐H 2 O and LiCl‐H 2 O working pair in absorption cooling systems based on genetic algorithm

“…In Equation (5), e is the availability per unit mass (kJ kg −1 ), _ E represents the availability flow rate (kW), _ m is the mass flow rate (kg s −1 ), and h 0 , s 0 , and T 0 are the enthalpy per unit mass (kJ kg −1 ), the entropy per unit mass (kJ kg −1 K −1 ), and the temperature (K) of the reference state, respectively. The value of rate of the availability destruction _ E D À Á can be obtained from the availability balance.…”

“…Therefore, there is an unprecedented need for an environment friendly energy saving cooling system. As a feasible option, vapor absorption cooling systems (VACSs) have received significant attention for harnessing waste and renewable energy sources, like vehicle waste heat, 3 solar energy, 4,5 geothermal energy, 6 and so on. VACS finds widely in industries, malls, and theatres where the above heat sources can be utilized to superheat the refrigerant.…”

Comparative assessment of different air‐conditioning systems for nearly/net zero‐energy buildings

“…For instance, Jani et al performed a simulation study on the solid desiccant assisted VC air‐conditioning system for a small test chamber under hot and humid environment to show the effect of ambient humidity and temperature on the proposed system's coefficient of performance ( COP ). Shaarawi and Ugla proposed the concept of hybrid cold and refrigerant energy storage device for continuous working of LiBr‐water based absorption air cooling system. They optimized the sizes of different components of the air‐conditioning system.…”

Effect of storage tanks on solar‐powered absorption chiller cooling system performance

“…The results showed that the cooling system continued to operate for a while after sunset and has an enhanced COP. El‐Shaarawi and Al‐Ugla studied to investigate four different configurations of hybrid storage for a 24‐hour operation of solar‐powered LiBr‐water absorption AC using ambient conditions of a family house in Dhahran City, Saudi Arabia that has a total daily cooling load of 120 kWh. They already stated that hybrid storage design for absorption chiller increases the performance and reduces the collector size.…”