• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.14-20
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• 1992

For the high quality and low cost agricultural crops in greenhouse cultivation, it is necessary to use natural energy as much as possible. In order to reduce the fossil fuel consumption and maximize the solar energy utilization in greenhouse heating, a latent heat storage material was developed as a relatively highly concentrative solar energy storage medium. And a solar energy-latent heat storage system was designed and constructed. The experimental research on greenhouse heating effect of the system was performed.

• Korean Journal of Construction Engineering and Management
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• v.20 no.2
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• pp.53-59
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• 2019

As solve the shortage problems of storage space for exhibition facilities, the South Korean government is establishing plans to expand storage space for exhibition facilities. From a medium- to long-term perspective, an energy-efficient storage space for exhibition facility is needed to implement efficient state budget execution and achieve national greenhouse gas reduction goals. In this regard, this study analyzed the energy consumption of storage space for exhibition facilities according to the use of absorption materials. To this end, a case study was conducted on 12 storage spaces for exhibition facilities in South Korea. Compared to the storage space using the absorption material, the storage space without using the absorption material showed an increase in HVAC system operation time by 47.50% during summer periods and 58.85% in non-summer periods. In particular, the analysis found that in the case of storage for 'H' exhibition facility, the energy cost was reduced by 2,721,700 won/year after remodeling work using the absorption material. It is expected that the findings of this study can help the government and the person in charge from construction companies to construct energy-efficient storage space room for exhibition facilities.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.80-85
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• 2009

Mathematical modeling and performance simulation results were shown for the solar thermal storage system which used heat pipe. The thermal storage system was composed of thermal storage tank and charging/discharging heat exchanger with one by the heat pipes. Heat pipe heat exchanger was attached to system, and could carry out charging and discharging to thermal storage tank at the same time. Height of the thermal storage tank was 600 mm, and that of the charging/discharging heat exchanger was 400 mm. Length of the heat pipe was the same as the total height of thermal storage system, and outer and inner diameter were 25.4 mm(O.D.) and 21.4 mm(I.D.) respectively. Diameter of the circular was 43 mm(O.D.), and fin geometries were considered as the design parameters. High temperature phase change material(PCM), $KNO_3$ and low temperature PCM, $LINO_3$ were charged to storage tank to adjust working temperature. Total size of thermal storage system able to get heat capacity more than 500 kW was calculated and the results were shown in this study. Number of heat pipe was required more than maximum 500, and total length of thermal storage system was calculated to the more than maximum 3 m at various condition.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.3
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• pp.311-318
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• 2016

This paper shows storage life estimation of next IR(infrared) flare material through accelerated degradation tests. Three temperature conditions for the accelerated degradation tests are 55, 65 and $75^{\circ}C$. Six performances of IR flare material are burning time, IR peak/continuous Intensity, total energy of near/mid-IR and color ratio, and they were measured after the tests. Storage life of the IR flare material was estimated through both analyzing the degradation data of those performances and applying distribution-based degradation models to the data. Over 30 years of storage life at $20^{\circ}C$ is estimated in terms of IR peak intensity with reliability 0.99 and confidence level 99 %. Additionally, 10 years of storage period at $21^{\circ}C$ would be equivalent to 68 days of accelerated test at $65^{\circ}C$ from the activation energy in Arrhenius model.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.51-52
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• 2023

A new shape-stable composite phase change material (PCM) have been produced via an easy and simple vacuum impregnation method. The composite PCM have been derived from almond shell biochar (ASB) as supporting material and capric acid (CA) as phase change material. Cost effective waste almond shells (AS) are renewable, eco-friendly, and rich in pores which enhance the possibility of CA impregnation. Therefore, in this study, three different ratios of CA (1:1, 1:2 and 1:3) have been incorporated in ASB to produce shape-stabilized phase change composites (ASCAs). Different techniques such as scanning electron microscopy (SEM), Fourier transform-infrared spectroscope (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) have been applied to evaluate the characteristics of ASCAs. The attained composite PCMs have exhibited shape stability with high latent heat storage, that makes it suitable for thermal energy storage applications.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.8
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• pp.305-310
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• 2016

A thermal storage systems was designed to correspond to the temporal or quantitative variation in the thermal energy demand, and most of its heat is stored using the latent and sensible heat of the heat storage material. The heat storage method using latent heat has a very complex phenomenon for heat transfer and thermal behavior because it is accompanied by a phase change in the course of heating/cooling of the heat storage material. Therefore, many studies have been conducted to produce an experimentally accessible as well as numerical approach to confirm the heat transfer and thermal behavior of phase change materials. The purpose of this study was to investigate the problems encountered during the actual heat transfer from an internal storage tank through simulation of the process of storing and utilizing thermal energy from the thermal storage tank containing charged PCM. This study used analysis methods to investigate the heat transfer characteristics of the PCM with simultaneous heating/cooling conditions in the rectangular space simulating the thermal storage tank. A numerical analysis was carried out in a state considering natural convection using the ANSYS FLUENT(R) program. The result indicates that the slope of the liquid-solid interface in the analysis field changed according to the temperature difference between the heating surface and cooling surface.

• International Journal of Computer Science & Network Security
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• v.24 no.6
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• pp.171-179
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• 2024

Decentralized energy production without greenhouse gas emissions from renewable energy sources despite their advantage and environmental impact suffers from the problem of intermittent and fluctuating supply depending on weather conditions. To overcome this problem, energy storage is essential to enable reliable and continuous supply of the load. Hydrogen is one of the most promising energy storage solutions because it is easily transportable and can be used as fuel or as a raw material for the production of other chemicals.In this article, we will focus on hydrogen energy storage techniques using photovoltaic systems. We will review the different types of hydrogen storage structuresfor several applications, including residential and commercial buildings, as well as industry and transportation (electric vehicles using PEFMC fuel cells).

• Journal of the Korean Ceramic Society
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• v.54 no.1
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• pp.9-22
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• 2017

Many new functional materials have been studied for efficient production and storage of energy. Many new materials such as sodium-based and sulfide-based materials have been proposed for energy storage, but research on Li batteries is still dominant. Due to the influence of environmental concerns regarding nuclear energy, interest in and research on fusion power are steadily increasing. For the commercialization of nuclear fusion, a design standard based on a considerable level of physical analysis and modeling is proposed. Nevertheless, limitations of existing materials in nuclear fusion environments limit practical applications. Tritium propagation material for continuous fusion reaction is one of the core materials, and therefore research on this material is being carried out intermittently. The key material for Li-based energy storage and tritium generation is the functional material Li-M-O. In this review, a structural description of functional Li-M-O system materials and technical trends for its applications are introduced.

• Journal of the Korean Chemical Society
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• v.65 no.2
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• pp.145-150
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• 2021

The present study describes a hands-on experiment to help students understand the concept of phase change or phase transition and its application in a phase change material (PCM). PCMs are substances that have the capability of storing and releasing large amounts of thermal energy. They act as energy storage materials that provide an effective way to save energy by reducing the electricity required for heating and cooling. Lauric acid (LA) was selected as an example of the PCM. Students investigated the temperature change of LA and the temperature (of air) inside the test tube. The differences in the temperatures of the systems helped students understand how PCMs work. A one-group pretest and posttest design was implemented with 34 grade-11 students in science and mathematics. Students' understanding was assessed using a multiple-choice test and a questionnaire. The findings revealed that the designed activity helped students understand the concept of phase change and its application to materials for thermal energy storage.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.4
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• pp.322-332
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• 2022

Energy storage capacitors based on dielectric ceramics with superior polarization properties and dielectric constant can provide much higher output power density due to their very fast energy charging/discharging rates, which are particularly suitable for operating pulsed-power devices. For an outstanding energy storage performance of dielectric capacitor, a large recoverable energy density could be derived by introducing a slim polarization-electric field hysteresis loop into dielectric materials by various technical approaches. Many research teams have explored various dielectric capacitor technologies to demonstrate high output power density and ultrafast charging/discharging behavior. This article reviews the recent research progress in high-performance dielectric capacitors for pulsed-power electronic applications.