scholarly journals Liquid based diurnal thermal storage

2021 ◽  
Author(s):  
Mojtaba Asgarian
Keyword(s):  
Phase Change ◽  
Heat Pump ◽  
Thermal Energy ◽  
Storage Tank ◽  
Heat Pumps ◽  
Constant Input ◽  
Flow Rates ◽  
Energy Rate ◽  
Input Mode ◽  
Whole Building Energy Simulation

A comprehensive study of using thermal energy storage (TES) tank was performed. In this report, the comprehensive literature review of various options of storing thermal energy in buildings was discussed. The objective of the project was to evaluate charging and discharging performance of a storage tank with and without phase change material (PCM) blocks. The general format of the energy balance for the storage tank considering losses, input energy, inlet and outlet mass flow rates, and PCM blocks was developed. Charging performance was analyzed by three different approaches. Initially, constant input thermal energy rate was considered to be delivered to the tank by different heat pumps from 4.5 kW to 9 kW heating capacity. Charging time, phase change process, and stored energy were analyzed under constant thermal energy rate input mode for charging process. Then, the effect of constant coil temperature on charging process was studied and results were compared to previous cases. Also, a solar assisted heat pump was implemented into the model to verify the effect of solar radiation on pre-heating the air for heat pump and how this process improves the overall charging progress of storage tank. Moreover, discharge procedure was discussed to evaluate various discharge modes based on different water draw flow rates. Based on this analyses developing a complete TRNSYS model of the tank is recommended in order to do whole building energy simulation.

scholarly journals Liquid based diurnal thermal storage

2021 ◽  
Author(s):  
Mojtaba Asgarian
Keyword(s):  
Phase Change ◽  
Heat Pump ◽  
Thermal Energy ◽  
Storage Tank ◽  
Heat Pumps ◽  
Constant Input ◽  
Flow Rates ◽  
Energy Rate ◽  
Input Mode ◽  
Whole Building Energy Simulation

A comprehensive study of using thermal energy storage (TES) tank was performed. In this report, the comprehensive literature review of various options of storing thermal energy in buildings was discussed. The objective of the project was to evaluate charging and discharging performance of a storage tank with and without phase change material (PCM) blocks. The general format of the energy balance for the storage tank considering losses, input energy, inlet and outlet mass flow rates, and PCM blocks was developed. Charging performance was analyzed by three different approaches. Initially, constant input thermal energy rate was considered to be delivered to the tank by different heat pumps from 4.5 kW to 9 kW heating capacity. Charging time, phase change process, and stored energy were analyzed under constant thermal energy rate input mode for charging process. Then, the effect of constant coil temperature on charging process was studied and results were compared to previous cases. Also, a solar assisted heat pump was implemented into the model to verify the effect of solar radiation on pre-heating the air for heat pump and how this process improves the overall charging progress of storage tank. Moreover, discharge procedure was discussed to evaluate various discharge modes based on different water draw flow rates. Based on this analyses developing a complete TRNSYS model of the tank is recommended in order to do whole building energy simulation.

scholarly journals Prospect for the using of heat pumps for heating of buildings in enterprise

2020 ◽  
Author(s):  
Z. Sirkо ◽  
◽  
V. Korenda ◽  
I. Vyshnyakov ◽  
O. Protasov ◽  
...  
Keyword(s):  
Water Supply ◽  
Heat Pump ◽  
Thermal Energy ◽  
Alternative Energy ◽  
Thermodynamic Cycle ◽  
Heat Pumps ◽  
The State ◽  
Hot Water ◽  
Alternative Energy Sources ◽  
Hot Water Supply

Heat pump - a device for transferring thermal energy from a source of low potential thermal energy to a consumer with a higher temperature. The thermodynamic cycle of a heat pump is similar to a refrigerating machine. Depending on the principle of operation, heat pumps are divided into compression and absorption. The most commonly used compression heat pumps. In recent years, numerous publications on the use of heat pump technology in heating and hot water supply facilities of various spheres - from individual homes to residential neighborhoods have appeared in various media. The authors of the publication have many years of experience in joint scientific and technical cooperation with leading technical universities and industrial organizations in the field of development and practical use of heat pump technology. The authors analyze the possibilities of introducing heat pumps at enterprises and organizations of the State Reserve System of Ukraine. It has been shown that the amount of expenses in comparison with central heating or operation of gas and electric boilers of similar power is several times smaller. It is noted that the implementation of heat pumps is a promising direction in the use of alternative energy sources to meet the heating, ventilation and hot water supply needs of buildings. The payback period from the introduction of heat pumps at enterprises is 4-9 years, depending on the location of the object and the type of source of low-temperature heat. The article meets the requirements of the State Tax Code of Ukraine and can be recommended for publication.

scholarly journals PARAFFIN AS PHASE CHANGE MATERIAL FOR THERMAL ENERGY STORAGE, HEATING APPLICATION

2021 ◽  
Vol 25 (Special) ◽  
pp. 3-108-3-113
Author(s):  
Ghufran G. Shakassi ◽  
◽  
Nagam O. Kariem ◽  
Mohammed J. AliAlatabe ◽  
◽  
...  
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Focal Points ◽  
Flow Rates ◽  
Long Time ◽  
Discontinuous Nature ◽  
Change Material

Liberally accessible sun based vitality utilization for residential and mechanical applications are ruined since of its discontinuous nature. The thermal energy storage (TES) framework utilizing both sensible and inactive warm has numerous advantages like expansive warm capacity in a unit volume and its isothermal behavior amid the charging and releasing forms. Since of these focal points, in later a long time, a part of investigate work has been going on to overcome issues like moo warm exchange the rates between warm exchange liquid and stage alter fabric (PCM) in both charging and releasing forms of the PCM-based TES framework. In the present experimental investigation results of a combined sensible and latent heat TES system integrated with a varying (solar) heat source is presented. Investigations are carried out in the TES system for different phase change materials (paraffin) by varying HTF flow rates and for various paraffin mass (2, 4, and 6) kg. Experiments are performed charging processes. The results show that the 2 kg paraffin mass shows better performance compared to other paraffin mass.

Thermohydraulic Analysis of Ground as a Heat Source for Heat Pumps Using Vertical Pipes

1996 ◽  
Vol 118 (4) ◽  
pp. 300-305 ◽  
Author(s):  
M. T. Kangas
Keyword(s):  
Computer Simulation ◽  
Heat Source ◽  
Heat Pump ◽  
Thermal Energy ◽  
System Performance ◽  
Thermal Effects ◽  
Heat Pumps ◽  
The Other ◽  
Heat Extraction ◽  
Energy Potential

In this study, the use of the ground as the heat source for a heat pump was studied by computer simulation. The heat extraction system consisted of vertical pipes drilled into the ground where groundwater was present. Along with available thermal energy, potential environmental effects, such as freezing and thermal pollution, were examined. It was found that the presence of groundwater enhances system performance by decreasing the possibility of freezing but, on the other hand, increases the range of thermal effects in the ground. The temperature of the ground as well as extraction arrangements also have a significant effect on system performance.

Experimental Testing of a Thermoelectric-Based Hydronic Cooling and Heating Device With Transient Charging of Sensible Thermal Energy Storage Water Tank

2008 ◽  
Author(s):  
Michael J. Kazmierczak ◽  
Sreenidhi Krishnamoorthy ◽  
Abhishek Gupta
Keyword(s):  
Energy Storage ◽  
Heat Exchanger ◽  
Heat Pump ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Storage Tank ◽  
Hot Water ◽  
System Component ◽  
Water Tank ◽  
Te Modules

Experiments were performed to charge either cold or hot water thermal energy storage tanks using a heat exchanger equipped with multiple thermoelectric (TE) modules. The primary objective was to design a simple, but effective, modular Peltier heat pump system component to provide chilled or hot water for domestic use at the appliance level, and when arranged in multiple unit combinations, a system that can potentially satisfy small home cooling and heating requirements. Moreover, when the TEs are directly energized using solar PV panels, the system provides a renewable, pollution free and off-the-grid solution to supplement home energy needs. The present work focuses on the design and testing of a thermoelectric heat exchanger component that consists of two water channels machined from two aluminum plates with an array of three or five thermoelectric modules placed in between to transiently cool and/or heat the water in the thermal energy storage tank. The water passing over either the cold or hot side of the TE modules is recirculated to charge the cold or hot thermal storage tank, respectively. The temperatures in the prototype Peltier heat exchanger test component and thermal energy water storage tank were measured during both cold tank charging and hot tank charging operation. The thermal efficiencies of TE heat pump cooling/heating system are reported. The effects of TE power input, number of TE units and rate of fluid flow are studied.

scholarly journals 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

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.

scholarly journals Optimization of Design Variables of a Phase Change Material Storage Tank and Comparison of a 2D Implicit vs. 2D Explicit Model

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2605
Author(s):  
Alicia Crespo ◽  
Gabriel Zsembinszki ◽  
David Vérez ◽  
Emiliano Borri ◽  
Cèsar Fernández ◽  
...  
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Storage Tank ◽  
Explicit Scheme ◽  
Computational Time ◽  
Slight Reduction ◽  
Change Material

In this study, a thermal energy storage tank filled with commercial phase change material flat slabs is investigated. The tank provides heat at around 15 °C to the evaporator of a seasonal thermal energy storage system developed under the EU-funded project SWS-Heating. A 2D numerical model of the phase changed material storage tank based on the finite control volume approach was developed and validated with experimental data. Based on the validated model, an optimization was performed to identify the number, type and configuration of slabs. The final goal of the phase change material tank model is to be implemented into the whole generic heating system model. A trade-off between results’ accuracy and computational time of the phase change material model is needed. Therefore, a comparison between a 2D implicit and 2D explicit scheme of the model was performed. The results showed that using an explicit scheme instead of an implicit scheme with a reasonable number of nodes (15 to 25) in the heat transfer fluid direction allowed a considerable decrease in the computational time (7 times for the best case) with only a slight reduction in the accuracy in terms on mean average percentage error (0.44%).

scholarly journals Flexibility Estimation of Residential Heat Pumps under Heat Demand Uncertainty

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5709
Author(s):  
Zhengjie You ◽  
Michel Zade ◽  
Babu Kumaran Kumaran Nalini ◽  
Peter Tzscheutschler
Keyword(s):  
Energy Storage ◽  
Heat Pump ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Heat Pumps ◽  
Hot Water ◽  
Maximum Temperature ◽  
Heat Demand ◽  
Residential Units ◽  
The Impact

With the increasing penetration of intermittent renewable energy generation, there is a growing demand to use the inherent flexibility within buildings to absorb renewable related disruptions. Heat pumps play a particularly important role, as they account for a high share of electricity consumption in residential units. The most common way of quantifying the flexibility is by considering the response of the building or the household appliances to external penalty signals. However, this approach neither accounts for the use cases of flexibility trading nor considers its impact on the prosumer comfort, when the heat pump should cover the stochastic domestic hot water (DHW) consumption. Therefore, in this paper, a new approach to quantifying the flexibility potential of residential heat pumps is proposed. This methodology enables the prosumers themselves to generate and submit the operating plan of the heat pump to the system operator and trade the alternative operating plans of the heat pump on the flexibility market. In addition, the impact of the flexibility provision on the prosumer comfort is investigated by calculating the warm water temperature drops in the thermal energy storage given heat demand forecast errors. The results show that the approach with constant capacity reservation in the thermal energy storage provides the best solution, with an average of 2.5 min unsatisfactory time per day and a maximum temperature drop of 2.3∘C.

Sign in / Sign up

Export Citation Format

Share Document