Thermal Energy Harvest and Reutilization by the Combination of Thermal Conducting Reactive Mesogens and Heat-Storage Mesogens

This study aims to assess the effect of adding twisted fins in a triple-tube heat exchanger used for latent heat storage compared with using straight fins and no fins. In the proposed heat exchanger, phase change material (PCM) is placed between the middle annulus while hot water is passed in the inner tube and outer annulus in a counter-current direction, as a superior method to melt the PCM and store the thermal energy. The behavior of the system was assessed regarding the liquid fraction and temperature distributions as well as charging time and energy storage rate. The results indicate the advantages of adding twisted fins compared with those of using straight fins. The effect of several twisted fins was also studied to discover its effectiveness on the melting rate. The results demonstrate that deployment of four twisted fins reduced the melting time by 18% compared with using the same number of straight fins, and 25% compared with the no-fins case considering a similar PCM mass. Moreover, the melting time for the case of using four straight fins was 8.3% lower than that compared with the no-fins case. By raising the fins’ number from two to four and six, the heat storage rate rose 14.2% and 25.4%, respectively. This study presents the effects of novel configurations of fins in PCM-based thermal energy storage to deliver innovative products toward commercialization, which can be manufactured with additive manufacturing.

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Thermal Energy Storage Performance of Tetrabutylammonium Acrylate Hydrate as Phase Change Materials

Applied Sciences ◽

10.3390/app11114848 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4848

Author(s):

Hitoshi Kiyokawa ◽

Hiroki Tokutomi ◽

Shinichi Ishida ◽

Hiroaki Nishi ◽

Ryo Ohmura

Keyword(s):

Energy Storage ◽

Heat Exchanger ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Phase Change Materials ◽

Heat Storage ◽

Solid Phase ◽

Agitation Rate ◽

Mechanical Agitation ◽

External Forces

Kinetic characteristics of thermal energy storage (TES) using tetrabutylammonium acrylate (TBAAc) hydrate were experimentally evaluated for practical use as PCMs. Mechanical agitation or ultrasonic vibration was added to detach the hydrate adhesion on the heat exchanger, which could be a thermal resistance. The effect of the external forces also was evaluated by changing their rotation rate and frequency. When the agitation rate was 600 rpm, the system achieved TES density of 140 MJ/m3 in 2.9 hours. This value is comparable to the ideal performance of ice TES when its solid phase fraction is 45%. UA/V (U: thermal transfer coefficient, A: surface area of the heat exchange coil, V: volume of the TES medium) is known as an index of the ease of heat transfer in a heat exchanger. UA/V obtained in this study was comparable to that of other common heat exchangers, which means the equivalent performance would be available by setting the similar UA/V. In this study, we succeeded in obtaining practical data for heat storage by TBAAc hydrate. The data obtained in this study will be a great help for the practical application of hydrate heat storage in the future.

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Efficient Operation Method of Aquifer Thermal Energy Storage System Using Demand Response

Energies ◽

10.3390/en14113129 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3129

Author(s):

Jewon Oh ◽

Daisuke Sumiyoshi ◽

Masatoshi Nishioka ◽

Hyunbae Kim

Keyword(s):

Energy Storage ◽

Power Consumption ◽

Thermal Energy ◽

Demand Response ◽

Thermal Energy Storage ◽

Heat Storage ◽

Storage System ◽

Total Power ◽

Operation Method ◽

Total Power Consumption

The mass introduction of renewable energy is essential to reduce carbon dioxide emissions. We examined an operation method that combines the surplus energy of photovoltaic power generation using demand response (DR), which recognizes the balance between power supply and demand, with an aquifer heat storage system. In the case that predicts the occurrence of DR and performs DR storage and heat dissipation operation, the result was an operation that can suppress daytime power consumption without increasing total power consumption. Case 1-2, which performs nighttime heat storage operation for about 6 h, has become an operation that suppresses daytime power consumption by more than 60%. Furthermore, the increase in total power consumption was suppressed by combining DR heat storage operation. The long night heat storage operation did not use up the heat storage amount. Therefore, it is recommended to the heat storage operation at night as much as possible before DR occurs. In the target area of this study, the underground temperature was 19.1 °C, the room temperature during cooling was about 25 °C and groundwater could be used as the heat source. The aquifer thermal energy storage (ATES) system in this study uses three wells, and consists of a well that pumps groundwater, a heat storage well that stores heat and a well that used heat and then returns it. Care must be taken using such an operation method depending on the layer configuration.

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Artificial Neural Network Simulation of Energetic Performance for Sorption Thermal Energy Storage Reactors

Energies ◽

10.3390/en14113294 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3294

Author(s):

Carla Delmarre ◽

Marie-Anne Resmond ◽

Frédéric Kuznik ◽

Christian Obrecht ◽

Bao Chen ◽

...

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Energy Storage ◽

Thermal Energy ◽

Temperature Difference ◽

Thermal Energy Storage ◽

Heat Storage ◽

Experimental Results ◽

Physical Models ◽

Artificial Neural

Sorption thermal heat storage is a promising solution to improve the development of renewable energies and to promote a rational use of energy both for industry and households. These systems store thermal energy through physico-chemical sorption/desorption reactions that are also termed hydration/dehydration. Their introduction to the market requires to assess their energy performances, usually analysed by numerical simulation of the overall system. To address this, physical models are commonly developed and used. However, simulation based on such models are time-consuming which does not allow their use for yearly simulations. Artificial neural network (ANN)-based models, which are known for their computational efficiency, may overcome this issue. Therefore, the main objective of this study is to investigate the use of an ANN model to simulate a sorption heat storage system, instead of using a physical model. The neural network is trained using experimental results in order to evaluate this approach on actual systems. By using a recurrent neural network (RNN) and the Deep Learning Toolbox in MATLAB, a good accuracy is reached, and the predicted results are close to the experimental results. The root mean squared error for the prediction of the temperature difference during the thermal energy storage process is less than 3K for both hydration and dehydration, the maximal temperature difference being, respectively, about 90K and 40K.

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Experimental evaluation of passive cooling using phase change materials (PCM) for reducing overheating in public building

E3S Web of Conferences ◽

10.1051/e3sconf/20183201001 ◽

2018 ◽

Vol 32 ◽

pp. 01001

Author(s):

Abdullahi Ahmed ◽

Monica Mateo-Garcia ◽

Danny McGough ◽

Kassim Caratella ◽

Zafer Ure

Keyword(s):

Environmental Quality ◽

Thermal Energy ◽

Phase Change Materials ◽

Heat Storage ◽

Passive Cooling ◽

Thermal Mass ◽

Indoor Environmental Quality ◽

Sensible Heat ◽

Storage Materials ◽

Heat Storage Materials

Indoor Environmental Quality (IEQ) is essential for the health and productivity of building users. The risk of overheating in buildings is increasing due to increased density of occupancy of people and heat emitting equipment, increase in ambient temperature due to manifestation of climate change or changes in urban micro-climate. One of the solutions to building overheating is to inject some exposed thermal mass into the interior of the building. There are many different types of thermal storage materials which typically includes sensible heat storage materials such as concrete, bricks, rocks etc. It is very difficult to increase the thermal mass of existing buildings using these sensible heat storage materials. Alternative to these, there are latent heat storage materials called Phase Change Materials (PCM), which have high thermal storage capacity per unit volume of materials making them easy to implement within retrofit project. The use of Passive Cooling Thermal Energy Storage (TES) systems in the form of PCM PlusICE Solutions has been investigated in occupied spaces to improve indoor environmental quality. The work has been carried out using experimental set-up in existing spaces and monitored through the summer the months. The rooms have been monitored using wireless temperature and humidity sensors. There appears to be significant improvement in indoor temperature of up to 5°K in the room with the PCM compared to the monitored control spaces. The success of PCM for passive cooling is strongly dependent on the ventilation strategy employed in the spaces. The use of night time cooling to purge the stored thermal energy is essential for improved efficacy of the systems to reduce overheating in the spaces. The investigation is carried within the EU funded RESEEPEE project.

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Constant-volume vapor-liquid equilibrium for thermal energy storage: investigation of a new storage condition for solar thermal systems

E3S Web of Conferences ◽

10.1051/e3sconf/202123803004 ◽

2021 ◽

Vol 238 ◽

pp. 03004

Author(s):

Abdullah Bamoshmoosh ◽

Gianluca Valenti

Keyword(s):

Energy Storage ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Exergy Analysis ◽

Heat Storage ◽

Storage Condition ◽

Liquid Equilibrium ◽

Liquid Systems ◽

Transfer Properties ◽

Vapor Liquid

The sector of thermal energy storage shows a number of alternatives that could have a relevant impact on the future of energy saving as well as renewable energy technologies. Among these, latent heat thermal energy storage technologies show promising results. Technologies that exploit solid-liquid phase change have already been widely proposed, but those technologies show common drawbacks limiting their application, such as high cost, low energy storage density and particularly low heat transfer properties. This work proposes to exploit the liquid-vapor phase transition in closed and constant volumes because it shows higher heat transfer properties. Consequently, the objective is to assess its energy storage performances in target temperature ranges. With respect to previous activity by the authors, this work proposes an exergy analysis of these systems, gives a methodology their deployment, and proposes a comparison between a new storage condition for solar thermal domestic hot water systems exploiting vapor-liquid equilibrium and conventional technologies. The exergy analysis is performed in reduced terms in order to have a generalized approach. Three hypothetical fluids with increasing degree of molecular complexity are considered in order to have a complete overview of the thermodynamic behavior of potential heat storage fluids. The analysis shows that the increased pressure of liquid systems has a major impact on exergy, resulting in vapor-liquid systems having less than 50% of the exergy variation of pressurized liquid systems. This is proven to have no impact on thermal energy storage. For the case study, the proposed methodology indicates that water itself is a strong candidate as a heat storage fluid in the new condition. Comparison shows that the new condition has a higher energy storage capacity at same volume. The useful temperature range is increased by 108% by setting a 10.5% volume vapor fraction at ambient temperature. The resulting improvement gives a 94% higher energy storage, with a maximum operating pressure of the system of less than 5 bar.

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Thermal Energy Storage Thermal Response Model With Application to Thermal Management of High Power-Density Hand-Held Electronics

Journal of Electronic Packaging ◽

10.1115/1.4005915 ◽

2012 ◽

Vol 134 (1) ◽

Cited By ~ 7

Author(s):

R. A. Wirtz ◽

K. Swanson ◽

M. Yaquinto

Keyword(s):

Energy Storage ◽

Phase Change ◽

Thermal Energy ◽

High Power ◽

Thermal Energy Storage ◽

Heat Storage ◽

Thermal Response ◽

High Power Density ◽

Storage Volume ◽

Change Material

An important design objective that is unique to hand-held units is the need to constrain two temperatures: the maximum temperature of the electronic components and the maximum skin temperature of the hand-held unit. The present work identifies and evaluates, through parametric modeling and experiments, the passive thermal energy storage volume characteristics and phase change material composite properties that are most suitable for thermal control of small form-factor, high power-density, hand-held electronics. A one-dimensional transient analytical model, based on an integral heat balance, is formulated and benchmarked. The model accurately simulates the heat storage/recovery process in a semi-infinite, “dry” phase change material slab. Dimensional analysis identifies the time and temperature metrics and nondimensional parameters that describe the heat storage/release process. Parametric analysis illustrates how changes in these nondimensional parameters affect thermal energy storage volume thermal response.

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Central heating by seasonal sensible heat storage of solar thermal energy

International Journal of Innovative Research and Scientific Studies ◽

10.53894/ijirss.v4i2.63 ◽

2021 ◽

Vol 4 (2) ◽

pp. 100-110

Author(s):

Abdul Mosaur Waseel ◽

Najib Rahman Sabory ◽

Hameedullah Zaheb ◽

Abdul Kareem Waseel

Keyword(s):

Thermal Energy ◽

Heat Storage ◽

Residential Buildings ◽

Economic Feasibility ◽

Solar Thermal ◽

Maintenance Cost ◽

Sensible Heat ◽

Solar Thermal Energy ◽

Central Heating ◽

Environmental Feasibility

Production of required thermal energy to heat residential buildings is a considerable issue in energy studies. Kabul city is a city in which the coal-fired central heating systems for providing the mentioned energy is in expansion process. And, coal as feeding source of these systems with generation of carbon dioxide (CO2) is the main cause of greenhouse gases (GHGs) emissions in winter. Fortunately, Kabul city has maximum solar radiation in summer warm season which can be used for fulfilling of this demand in winter cold season. The method which can perform this task is the central heating by seasonal sensible heat storage of solar thermal energy. But, the economic and environmental feasibility and viability of this method is a discussable issue. In this study, the central heating by seasonal sensible heat storage of solar thermal energy and its economic and environmental feasibility and viability is studied. It is tried that this system is compared in a logical method with current coal-fired systems. The economic feasibility study is accomplished by comparison of initial or capital cost and annual operation and maintenance cost with the usage of existing data and thermodynamic analytic methods. The environmental viability study is accomplished by comparison of annual emissions of CO2 with the usage of online emissions calculator. Unfortunately, it is found that seasonal sensible heat storage of solar thermal energy is not an economically feasible method for central heating due to its high initial cost and cannot be used in an economically beneficial manner for central heating. But fortunately, it is an environmentally viable method and environmentally friendly way due to its no and/or zero CO2 emissions. To sum up, it is suggested that, this method should be used for district heating which can make this system economically feasible.

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Analysis of Thermal Energy Storage to a Combined Heat and Power Plant

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38182 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1313-1320

Author(s):

Shahim Nisar

Keyword(s):

Energy Storage ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Energy Demand ◽

Power Plants ◽

Heat Storage ◽

Packed Bed ◽

Water Tank ◽

Latent Heat Storage ◽

Storage Methods

Abstract: Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included.

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