Hybrid thermal energy storage with phase change materials for solar domestic hot water applications: Direct versus indirect heat exchange systems

A full-scale thermal energy storage system using phase change materials (PCM) is experimentally investigated for solar and geothermal applications. The system consists of a rectangular tank filled with PCM and a staggered fin tube heat exchanger (HE). The system is designed for the production of Domestic Hot Water (DHW) based on the EU Commission Regulation No 814/2013 [1] requirements. The characteristics that are studied are the stored energy density of the system, the heat transfer rate through the HE during the charging and discharging processes, the adequacy of produced hot water amount and the storage efficiency of the tank. The results of the experiments confirmed the potential of the system to meet several prerequisites of a DHW installation and in addition to make the operation of the coupled solar collector or ground heat pump efficient.

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Analysis of Flow Through Packed Bed of Spheres Containing Phase Change Materials for Thermal Energy Storage Applications

Volume 6: Energy ◽

10.1115/imece2019-12185 ◽

2019 ◽

Author(s):

Vinit V. Prabhu ◽

Ethan Languri ◽

Kashif Nawaz

Keyword(s):

Thermal Conductivity ◽

Energy Storage ◽

Response Time ◽

Phase Change ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Response Rate ◽

Packed Bed ◽

Hot Water

Abstract The research on thermal energy storage (TES) systems have received a lot of attention in recent decades for sustainable use of thermal energy in various industrial and residential applications. The existing challenge in designing the TES is the response time of charging and discharging cycles that keeps these systems away from wide utilization in industries. Literature data show that beside the low thermal conductivity of most phase change materials (PCMs) as active media in TES systems, the poor flow distribution may be another factor affecting the response rate. This study aims to considerably reduce the response time by packing the PCMs in a bed of spheres made of high thermal conductivity material. The response rate during the charging cycle is studied numerically by passing hot water at 70 °C over the packed bed of spheres. The numerical analysis is performed using ANSYS Fluent 19. The PCM used in this study is a paraffin and has a melting point of 48 °C. The response rate of the system is studied and it is compared to other similar systems mentioned in literature. The amount of energy storage is also studied by changing the flow rate of water.

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Heat Exchange Analysis on Latent Heat Thermal Energy Storage Systems Using Molten Salts and Nanoparticles as Phase Change Materials

Advancements in Energy Storage Technologies ◽

10.5772/intechopen.73672 ◽

2018 ◽

Author(s):

Adio Miliozzi ◽

Raffaele Liberatore ◽

Daniele Nicolini ◽

Manila Chieruzzi ◽

Elisabetta Veca ◽

...

Keyword(s):

Energy Storage ◽

Heat Exchange ◽

Phase Change ◽

Latent Heat ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Molten Salts ◽

Phase Change Materials ◽

Storage Systems ◽

Thermal Energy Storage Systems

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Techno-Economic Analysis of a Heat Pump Cycle Including a Three-Media Refrigerant/Phase Change Material/Water Heat Exchanger in the Hot Superheated Section for Efficient Domestic Hot Water Generation

Applied Sciences ◽

10.3390/app10217873 ◽

2020 ◽

Vol 10 (21) ◽

pp. 7873

Author(s):

Johann Emhofer ◽

Klemens Marx ◽

Tilman Barz ◽

Felix Hochwallner ◽

Luisa F. Cabeza ◽

...

Keyword(s):

Energy Storage ◽

Heat Exchanger ◽

Economic Analysis ◽

Phase Change ◽

Heat Pump ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Hot Water ◽

Domestic Hot Water ◽

Change Material

Integration of a three-media refrigerant/phase change material (PCM)/water heat exchanger (RPW-HEX) in the hot superheated section of a heat pump (HP) system is a promising approach to save energy for domestic hot water (DHW) generation in multi-family houses. The RPW-HEX works as a desuperheater and as a latent thermal energy storage in the system. The latent thermal energy storage is charged during heating and cooling operation and discharged for DHW production. For this purpose, the water side of the RPW-HEX is connected to decentralized DHW storage devices. DHW consumption, building standards and climate, energy prices, material costs, and production costs are the constraints for the selection of the optimal storage size and RPW-HEX design. This contribution presents the techno-economic analysis of the RPW-HEX integrated into an R32 air source HP. With the aid of experimentally validated dynamic computer models, the optimal sizing of the RPW-HEX storage is discussed to maximize energy savings and to minimize the investment costs. The results are discussed in the context of a return of investment analysis, practical implementation aspects and energetic potential of the novel technology.

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Experimental Study of Thermal Energy Storage in Solar System Using PCM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.1027 ◽

2012 ◽

Vol 433-440 ◽

pp. 1027-1032 ◽

Cited By ~ 9

Author(s):

B. Kanimozhi ◽

B.R. Ramesh Bapu

Keyword(s):

Energy Storage ◽

Solar Energy ◽

Phase Change ◽

Latent Heat ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Storage System ◽

Hot Water ◽

Copper Tube

This paper summary the investigation and analysis of thermal energy storage extracted from solar heater and use for domestic purpose. Choosing a suitable phase change materials paraffin wax used for storing thermal energy in insulation tank. The tank carries minimum of 45 liters capacity of water and 50 numbers copper tubes each copper tube carries minimum of 100 grams PCM materials. Inside the tank phase change materials are receiving hot water from solar panel. This solar energy is stored in Copper tubes each copper tube contains PCM Materials as latent heat energy. Latent heat is absorbed and stored in Copper tubes .Large quantity of solar energy can be stored in a day time and same heat can be retrieved for later use. The tank was instrumented to measure inlet and outlet water temperature. The differences of temperature of the water is measured in a definite interval of time have been noted then calculating heat transfer rate and system effectiveness. The heat storage system is to be applied to store solar energy and the stored heat is used for domestic hot water supply system.

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