Thermal Energy Storage using PCM for Solar Domestic Hot Water Systems: A Review

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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Evaluating a prototype compact thermal energy storage tank using paraffin-based phase change material for domestic hot water production

E3S Web of Conferences ◽

10.1051/e3sconf/201911600016 ◽

2019 ◽

Vol 116 ◽

pp. 00016

Author(s):

George Dogkas ◽

John Konstantaras ◽

Maria K. Koukou ◽

Vassilis N. Stathopoulos ◽

Luis Coelho ◽

...

Keyword(s):

Energy Storage ◽

Phase Change ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Storage System ◽

Energy Storage System ◽

Hot Water ◽

Domestic Hot Water ◽

Tube Heat Exchanger

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

Renewable Energy ◽

10.1016/j.renene.2019.08.121 ◽

2020 ◽

Vol 147 ◽

pp. 77-88 ◽

Cited By ~ 18

Author(s):

M.Y. Abdelsalam ◽

H.M. Teamah ◽

M.F. Lightstone ◽

J.S. Cotton

Keyword(s):

Energy Storage ◽

Heat Exchange ◽

Phase Change ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Hot Water ◽

Domestic Hot Water

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Performance Analysis of Solar-Assisted Ground-Coupled Heat Pump Systems with Seasonal Thermal Energy Storage to Supply Domestic Hot Water for Campus Buildings in Southern China

Sustainability ◽

10.3390/su13158344 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8344

Author(s):

Jin Zhou ◽

Zhikai Cui ◽

Feng Xu ◽

Guoqiang Zhang

Keyword(s):

Energy Storage ◽

Solar Energy ◽

Heat Pump ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Heat Balance ◽

Solar Collector ◽

Hot Water ◽

Domestic Hot Water ◽

Ground Coupled Heat Pump

The supply of domestic hot water (DHW) on college and university campuses is indispensable and is also one of the main components of campus energy consumption. The density of residential patterns and similar occupancy behavior of college students make it economical to use centralized systems to cover the DHW demand, and utilization of solar energy can make the systems more economical. Seasonal thermal energy storage (STES) is a promising key technology that can minimize the imbalance between the availability of solar energy and thermal energy demand. In this paper, a solar-assisted ground-coupled heat pump (SAGCHP) system that meets the DHW demand of 960 students was investigated by means of dynamic simulation and energy-economic analysis. The simulation results in terms of the underground heat balance are compared with a standalone GCHP system and a SAGCHP system without STES. Results show that heat recharging operations during university summer and winter breaks (when there are minimal students on campus) lead to improved underground heat balance and energy performance. Finally, a sensitivity analysis on system performance was carried out by varying solar collector arrays. It was found that there exists an optimal value of solar collector area to achieve the lowest system lifecycle cost (LCC).

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