scholarly journals RE-EVALUATION OF THE EGYPTIAN CODE OF HOUSING AND ENERGY CONSUMPTION WITH EMPHASIS ON SHADING DEVICES ROTATION ANGLES

Author(s):  
Tarek M.Kamel ◽  

The passive system technique is dynamically used as an alternative to the active system, in order to minimize the peak loads and the total EUI in kWh/ m2 for any building prototype. Sun breaker or shading device is a basic traditional method and Mashrabiya previously used for privacy and reduces the heat gained and emitted from sun`s rays, in addition to the fabricated wood material and its specs of bad conductor. the study aims to investigate the effect of rotational shading devices around the y-axis, will the rotation have a significant impact on the EUI or not? The research methodology is built upon generative modeling tool of parametric design, Rhinoceros Version 6.0, with the cooperation of Grasshopper, Ladybug& Honeybee, and Toolbox. Five hundred running simulations are carried out to determine the optimal angle of rotation with maximum reduction in cooling loads, and the interpretation is 30°. Two linear regression equations are derived out of this valuable study to deduce the correlation between independent and dependent variables when the sun breaker material is matt or reflective, and how the total EUI kWh/m2 can be minimized?

2015 ◽  
Vol 23 (03) ◽  
pp. 1550023 ◽  
Author(s):  
Yeo Beom Yoon ◽  
Rashmi Manandhar ◽  
Kwang Ho Lee

Many studies have been done to study the advantage of using window shading devices as a means of controlling solar penetration into the building. Shading devices like blinds have been proved to have a significant effect on the heating and cooling load of the building. As it is easier and less costly to change blinds than changing the window system in a building, using blinds is a very effective way of improving building performance. Although many studies have been done, mostly the study focuses on window that is oriented towards the south. As it is obvious that in a real building windows can be facing any direction, in this study the effect of blinds on heating and cooling loads of a building has been done, when the design of blind is either horizontal or vertical, when it is placed either inside or outside and when the slat angle automatically changes based on either solar energy received on vertical wall or on horizontal surface (roof).


Vestnik MGSU ◽  
2021 ◽  
pp. 655-665
Author(s):  
Chan Ngoc Tran ◽  
Nguyen Thi Khanh Phuong ◽  
Ekaterina V. Gorbarenko

Introduction. The article proposes a new energy efficiency assessment method based on a new technique used to calculate the window heat gain. The proposed method takes account of the coefficient of irradiance reduction by the sun shading device. The study was carried out for the shading device of the egg-crate type. Materials and methods. Calculations are based on the projection of a sunbeam performed for a fraction of a window area in the shade. They take account of the coefficient of irradiance reduction applied due to the presence of the sun shading device. A shading device reduces the irradiance, caused by diffused solar radiation, and coefficient Kbt is applied to demonstrate this process. This coefficient was identified in an experiment and expressed in the form of regression equations. To evaluate the energy efficiency with regard for the effectiveness of shading devices, coefficient of solar radiation gain reduction β was developed. This coefficient is described by the ratio of the value of solar radiation incoming through a glazed window in the presence of shading device QK to the value of solar radiation incoming through a glazed window that has no shading QKo. The software programme was used to verify the calculations of the heat gain from the solar radiation incoming through the window system with regard for the shading device in various geographical regions in summer (in Hanoi and Moscow). Results. The results, obtained using the proposed methodology and the observation data, show an insignificant difference in the relative value of β; and they demonstrate a major error when qwindow, or the absolute value of heat entering the room, is taken account of. The heat load, incoming through the window system, is down by 42–45 % in Moscow and by 45–53 % in Hanoi in the hottest period of the year if shading devices are used. Conclusions. The proposed methodology and computer software, used for a quick assessment of the energy efficiency of a window system equipped with shading devices, allow to design building envelopes that feature high energy efficiency in terms of air conditioning systems, given that coefficient of radiation gain reduction β is taken account of.


2021 ◽  
Vol 9 (1) ◽  
pp. 28-39
Author(s):  
Sara Dh. Bahaadin ◽  
Binaee Y. Raof ◽  
Hendren Abdulrahman

High-rise residential buildings are increasing worldwide, including cities in the Kurdistan Region of Iraq. Therefore, creating sustainable environments in and around these residential buildings are becoming an important problem. Improving energy efficiency in buildings has received critical attention worldwide. Countries have developed national sustainability strategies that lead to the lower energy consumption while maintaining comfort, reducing energy consumption, and minimizing harmful emissions. In this paper, an analysis of the impact of external shading devices in high-rise residential buildings on energy consumption of a 13-storey building in Sulaimani city is studied. The study is focused on fixed shading elements, explaining the influence of the design of vertical and horizontal shading devices on the total energy consumption of this type of building. The results show that both a single fixed horizontal blind with a depth of 20 cm and a triple vertical shading with the same depth are considered useless. The reduction in cooling loads by two fixed horizontal louvers almost doubled compared to a single fixed horizontal shading with 20 cm. Moreover, triple fixed horizontal louvers with 40 cm have almost the same effect on reducing cooling loads as triple fixed louvers with 60 cm. On the other hand, a triple fixed horizontal shading device with 60 cm has twice the effect on reducing annual cooling loads as a triple fixed vertical shading device with 60 cm.


2010 ◽  
Vol 20 (1) ◽  
pp. 75-90 ◽  
Author(s):  
Taeyon Hwang ◽  
Jeong Tai Kim

This study investigated the effects of indoor lighting on occupants’ visual comfort and eye health and to contribute to the management and maintenance of buildings. The illuminance of the working plane and windows at Samsung Corporation Headquarters were measured, and 2744 healthy occupants of Samsung Corporation were surveyed regarding the indoor lighting environment via the company’s intranet for 1½ years. This building was certified with the highest ranking by Korea’s Green Building Council. The cumulative data reflected the management and maintenance of the building, such as screen-type shading devices automatically controlled by seasons and time, improvement of visual display terminal glare by the veiling reflection on monitors, efficiency of artificial lighting arrays, and so on. The data were analysed for occupants’ visual comfort and eye health. The result showed that daylighting could improve the occupants’ psychological health and productivity. The screen-type shading device could intercept direct sunlight and reduce annoyance glare. However, the indoor lighting and visual environment of the building were poor. After examining the questionnaire feedback concerning improvements, the occupants’ annoyance ratio was significantly reduced, and approximately 5% of the occupants’ annoyance ratio was deemed to be caused by personal characteristics related to the lighting of the environment.


Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 348
Author(s):  
Sahar Magri Elouadjeri ◽  
Aicha Boussoualim ◽  
Hassan Ait Haddou

The present study investigates the effect of fixed external shading devices’ geometry on thermal comfort, daylighting and energy demand for cooling and heating in the hot and dry climate of the city of Ghardaïa (Algeria). A parametric analysis was performed by using three software: RADIANCE 2.0 and DAYSIM 3.1 for daylighting simulation and TRNSYS.17 for thermal dynamic simulation. Three shading device parameters were assessed: the spacing between slats, the tilted angle and the slats installation. The vertical shading angle “VSA” is fixed; it is equal to the optimum shading angle measured for Ghardaïa. The simulation results indicate that fixed external shading devices have a significant impact on decreasing the energy demand for cooling; however, they are unable to reduce the total energy demand since they significantly increase heating loads. It was found that fixed external shading devices remove all risks associated with glare in summer by decreasing illuminance close to the window; however, they do not improve daylighting performance in winter because of glare. We note that even if the vertical shading angle “VSA” was the same for all cases, these did not present the same thermal and luminous behavior. This is mainly due to the amount and the way that the solar radiation penetrates space.


2019 ◽  
Vol 11 (24) ◽  
pp. 7096
Author(s):  
Ho-Jeong Kim ◽  
Chang-Seok Yang ◽  
Hyeun Jun Moon

This study presents a multi-objective parametric design tool for four-axis surround-type movable shading device using solar position tracking in Seoul, South Korea. In order to explore large numbers of possible forms of shades, generic algorithms are utilized with real-time simulation of the performative criteria such as solar radiation, daylight glare probability (DGP), and solar shielding rate on window surface. This study outlines a workflow using a multi-objective engine called Octopus that runs within Grasshopper 3D, a parametric design tool, in addition to environmental performance simulation plug-in Ladybug. The workflow utilizes a performance-based design tool, which allows the designer to explore, sort, and filter solutions, and visually compare alternative solutions in terms of energy saving and indoor daylight quality in order to determine the optimal form of shade changing its shape every one hour. The result of deriving and analyzing the optimal shade shape through the genetic algorithm proposed in this study is as follows: On the one hand, on the summer solstice, shade shapes with shielding areas of almost 100% should be derived to achieve the most effective reduction of the direct solar radiation. The proposed movable shading device reduced direct solar radiation by 52.40% and 57.20% in the south- and east-facing windows, respectively. On the other hand, in winter when solar heat gain is important, the absence of sunshade is optimal in terms of heating load. However, in order to improve the indoor light environment, it is confirmed that it is possible to derive a certain shape of sunshade according to the sun’s trajectory. On the winter solstice, the problem of glare arises from 10:00 to 15:00 in the south and 10:00 in the east. Therefore, the proposed four-axis movable shading device can be configured to have a minimum protrusion length satisfying DGP less than 0.35 in winter.


2021 ◽  
Vol 8 (3) ◽  
pp. 157
Author(s):  
Aimi Zahirah Zulkarnain ◽  
Mohd Najib Mohd Salleh ◽  
Zalena Abdul Aziz

Daylighting is interpreted as natural sunlight allowed into an indoor space. Passive lighting strategies are considered fundamental in achieving a high performing sustainable building, which affects the visual and thermal comfort, and energy performance of a building. Many strategies in controlling daylighting are known, however, the wrong implementation can lead to a negative effect. The results obtained need to reach a balance between daylighting and thermal performance. This review is conducted to analyse the concept and factors that affect the balance through different research parameters. The performance factors include energy, comfort and perception or view. The different methods of achieving the balance are categorized into three, which are parameter relation, combination, and multi-objective optimization. Building shading devices are considered as one of the major solutions to reach thermal-daylighting balance. Through a comprehensive review, adjustable shading control is recommended as a better option for building shading device for buildings to achieve the optimum balance.


Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2790 ◽  
Author(s):  
Carmen Calama-González ◽  
Rafael Suárez ◽  
Ángel León-Rodríguez

Most educational buildings in southern Spain do not meet current energy requirements as weak thermal envelopes and the lack of cooling systems lead to severe discomfort in classrooms, especially when temperatures are above 30 °C. Given that global warming is expected to worsen this situation in coming decades, one of the first steps to be taken is to protect window openings from high levels of solar radiation by adding shading devices to reduce indoor temperatures and improve visual comfort. The aim of this research is to evaluate the reduction in thermal and lighting consumption in a classroom where a solar protection system in the form of an egg-crate shading device was installed. Two classrooms—one with an egg-crate device and another with no shading system—were monitored and compared for a whole year. The use of an egg-crate device in these classrooms reduced indoor operative temperatures during warmer periods while also improving indoor natural illuminance levels. Moreover, annual electric air conditioning consumption decreased by approximately 20%, with a 50% reduction in electric lighting consumption. These savings in electricity were largely conditioned by the use patterns observed in these ambient systems.


2013 ◽  
Vol 816-817 ◽  
pp. 875-881 ◽  
Author(s):  
R. Sairam ◽  
P.L. Raviteja ◽  
A. Naresh

There are many reasons to control the amount of sunlight admitted into a building. In warm, sunny climates excess solar gain may result in high cooling energy consumption. In cold and temperate climates winter sun entering south-facing windows can positively contribute to passive solar heating; and in nearly all climates controlling and diffusing natural Illumination will improve day lighting. A Well-designed sun control and shading devices can dramatically reduce building peak heat gain and cooling requirements and improve the Natural lighting quality of building interiors. In this casestudy Shading Devices commonly found in India are evaluated to find Optimized Shading Device for Hot-Dry Climate of South India


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Seok-Hyun Kim ◽  
Kyung-Ju Shin ◽  
Hyo-Jun Kim ◽  
Young-Hum Cho

In South Korea, the evaluation criteria for installing shading devices are defined by regulations, but the standards of design methods are not clearly established. The installation of shading devices has become mandatory for some public buildings due to revised regulations. Therefore, a design of horizontal shading device is required, and indoor environmental problems which may occur due to their installation should also be taken into consideration. This research aimed to propose a design which takes into account the energy consumption which may occur if the horizontal shading device is installed and suggests an improved design method of horizontal shading devices when they are installed. Consequently, it was confirmed that as the protrusion of the horizontal shading device becomes longer, the incoming daylight is reduced and the indoor intensity of illumination becomes lower, and thus more lighting energy may be consumed in a room where the shading device is installed than in the one where it is not. Therefore, annual energy consumption was calculated by applying the lighting control and it was found that the total energy consumption decreased by the reduction of air-conditioning and fans and lighting energy consumption.


Sign in / Sign up

Export Citation Format

Share Document