• KIEAE Journal
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• v.17 no.2
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• pp.29-34
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• 2017

Purpose: Recently, significant heat loss through the window takes place in buildings. Nevertheless, there exists little literature concerning the exterior horizontal shading devices and the design criteria are not clearly settled yet. Applying the exterior horizontal shading devices is more efficient as compared to the interior shading devices in that solar radiation can be directly blocked before passing through the window or the envelope. The purpose of this study is to reduce the internal load by designing the exterior horizontal shading devices and verify the degree of reduction in energy consumption. Method: This study aims to reduce energy consumption in cooling and heating through proposing proper length and shape of the exterior horizontal shading devices in public buildings. In the process, actual energy data and the Design Builder simulation program are utilized. In addition, economic aspect is considered to figure out the optimal length of the exterior horizontal shading devices that maximizes efficiency. Result: As a result, the proper length and shape of the exterior horizontal shading devices are provided as follows: 1) Energy consumption in cooling and heating is minimized when the exterior horizontal shading devices are designed as 0.5m*2. 2) Electricity bill is the lowest when the exterior horizontal shading devices are designed as 3.3m*2. The gap between maximum and minimum electricity bill is about 7.8~14%.

• KIEAE Journal
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• v.16 no.5
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• pp.65-71
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• 2016

Purpose : The solar shading device carries out roles in a reduction of the cooling load and an improvement of the thermal comfort of occupants by adjusting incident solar radiation. In addition, The shading device enhances the visual sensation comfort by controlling the optical properties. In order to improve building performance and comfort of occupancy, interests in application of the shading devices are getting increasing. This study investigated the application and effectiveness of the external shading device design using statistical analysis. The outcome of this paper could be utilized for the realization of status quo and for an estimation of effectiveness of the shading device Method : The period of data gathering was between 2003 and 2014 and total 459 cases of practical building project were investigated. Firstly, this study defined qualification of the shading devices; the shading device should have minimum protruding lengths of 150mm to outside and have the function of shading control. This paper investigated application rate of the shading device in real project, regional rate of application, annual change of application, materials and types. Result : The statistical analysis showed that the application rate of shading devices was 25.7% in total 459 building design projects. The application rate in central and southern region was 25.3% and 27.0% respectively. Meanwhile, Jeju region showed 22.2%, which was the lowest rate although this area needs more shading devices. The application number of the shading device was the smallest in 2007, but the rate gradually increased after that. The applications was the largest in 2014 due to growing interest of the shading devices in the building.

• Journal of the Korean Solar Energy Society
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• v.34 no.3
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• pp.12-20
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• 2014

There is no comprehensive consensus of the control patterns people op::rate shadings or the motivating factors that influence their decisions. Patterns of shading devices use can affect the energy consumption of buildings. Therefore, this study aims to analyze shading device usage patterns based on the physical factors that can affect occupants behavior. First, control patterns of indoor shading devices in apartment buildings were monitored by taking pictures. Next, frequency of shading device use together with their shading portions was analyzed based on two physical factors such as window orientation and floor level. The results showed that about 35% of the monitored apartment buildings utilized indoor shading devices. Also, the south-facing apartments were more dynamically used than their east-facing counterparts. On the contrary, there was no general trend in regards to the shading operation patterns.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• KIEAE Journal
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• v.14 no.5
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• pp.67-73
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• 2014

This study aims at examining kinetic efficient shading systems and their implementation methods. These days, the importance of the shading devices are getting more significant due to the energy problem. Cordially, suitable shade designs are required as an important element for the exterior envelope of the building. This study employs the optimal shading design as an efficient shading method with the kinetic system that can be converted actively by the altitude of the sun. The proposed kinetic shading system works not only as a lightshelf in case the altitude of the sun is high but also as a vertical louver when the sun is getting lower in order to block the direct sunlight. This study has analyzed the thermal performance and shading coefficient of the kinetic shading system in comparison to existing fixed shading devices using the Ecotect. The results, in sum, conclude that the suggested kinetic shading system could decrease direct sunlights 26.2% more than the existing shading methods.

• Journal of the Korean Solar Energy Society
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• v.29 no.3
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• pp.28-36
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• 2009

The majority of fixed shading devices are installed in the exterior of a building in order to dissipate the heat absorbing from the sun and to prevent the direct sunlight. In designing external shading devices for windows, many requirements must be considered simultaneously; solar geometry, optimum energy performance, multi-purpose usage and design factors etc.. In order Lo satisfy these requirements, we suggests the folding shading device and its optimum design methodology. Also we analyzed the thermal performance using the IES_VE program according to various operating modes and compared with existing shading devices. The results show that proposed device reduce about $1.90{\sim}22.40%$ in cooling load and about $1.09{\sim}24.22%$ in heating load in comparison with existing ones.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.2
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• pp.4-15
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• 2008

The purpose of this study was to evaluate the characteristics of daylighting environment in classroom of an school building due to the external shading devices such as fixed louvers, light shelves and exterior venetian blinds. In this study, we have made a field research with regard to the facade design in classroom of an school building. And we have made a classification of external shading devices considering the design parameters. Finally, through RADIANCE simulation, we have calculated the spatial distribution of illuminance, uniformity ratio of illuminance and daylight factors. The results of this study will provide the building designer with the basic daylighting performance data at early design stages.

• Journal of the Korean Solar Energy Society
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• v.36 no.4
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• pp.1-9
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• 2016

The purpose of this study was to compare heat shading performance of various blind types in summer. 4 types of blinds were employed and the results are summarized as follows: 1) There were significant differences in indoor thermal environment and heat shading performance between different heat shading devices, and functional blinds demonstrated relatively superior heat shading performance. 2) Indoor long wave radiation influx measures were lowest for the coating roll blind (Blind B), followed by the coating venetian blind (Blind C), the venetian blind (Blind A), the roll blind, and not having any blinds at all. 3) Such examination results carry implications to reduce cooling load and enhance the indoor environment.

• Land and Housing Review
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• v.12 no.1
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• pp.129-137
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• 2021

External shading devices are well known solar control devices that can help reduce the cooling load of commercial buildings. For this study, experiments were conducted to examine the feasibility of shading devices in reducing both the cooling and heating loads. The influence of sky radiant cooling during winter was verified for the external shading device, internal roller blind, and window. Results can be summarized as follows. The temperature difference between the inner and outer surfaces of the window with the external shading device was 11.8℃ compared to 14.6℃ for one without the external shading device. This 2.8℃ difference was due to heat exchange by sky radiation when the surface temperature of the shading device was lower than the ambient outdoor air temperature. The roller blind resulted in a lower temperature of 0.8℃ compared to the average temperature of the window's air cavity. This was due to heat exchange by sky radiation of the roller blind surfaces. Without shading devices, the outside surface temperature of the window is about 3℃ higher. The study also found that when external shading devices were installed on both the southwest and southeast sides, the outside surface temperature of the windows were lower on the southwest side than the southeast side.

• Journal of the Korean Solar Energy Society
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• v.38 no.6
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• pp.1-14
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• 2018

The shading device on the window of the building can be an passive solution to reduce the cooling load and lighting energy, as well as improving the indoor comfort. It is also an architectural element that must be considered for building energy-efficient buildings such as eco-buildings and zero-energy buildings. However, due to various building environments and various shading devices, the installation of excessive shade may lead to the risk of losing the effectiveness of windows. In this study, we propose a method for optimal automatic control of shading device and evaluate its effectiveness by energy analysis of several shading devices.