Systems with Low Energy Consumption
Samira Ghorbani; Masoud Taheri Shahraeini; Mostafa Mohajerani
Abstract
Daylight serves as a fundamental element in the design of sustainable buildings, significantly contributing to energy efficiency and occupant visual comfort. However, the uncontrolled penetration of natural light may result in issues such as glare and uneven daylight distribution within interior spaces. ...
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Daylight serves as a fundamental element in the design of sustainable buildings, significantly contributing to energy efficiency and occupant visual comfort. However, the uncontrolled penetration of natural light may result in issues such as glare and uneven daylight distribution within interior spaces. An effective approach to daylight management involves utilizing light shelves, which enhance interior daylight penetration while mitigating excessive brightness near windows. This study examines the impact of light shelves on daylight distribution improvement through simulations conducted with the Ladybug plugin within the Grasshopper plugin, integrated into the Rhino modeling software. In this process, the building model was developed under specific climatic conditions, and key light shelf parameters, including depth, angle, and surface reflectivity, were evaluated. The analysis was carried out based on illuminance metrics. Among the nine measurement points, the three terminal points in the darkest areas were selected to assess the performance of the light shelf in improving daylight distribution. This study focused on evaluating the improvement in daylight levels achieved by the selected light shelf scenario at these points and the average illuminance of the rear work surfaces that required enhancement on December 21 and June 21. As a result, the implementation of light shelves in the targeted studio contributed to a 22%–30% enhancement in daylight availability.
Systems with Low Energy Consumption
Ali Fahim; Ahmad Nazari; mohammad Zamen; Amirreza Salamat Asrami
Abstract
A significant portion of energy consumption, particularly during the summer, is attributed to cooling demands in buildings. The most common methods for providing cooling are vapor compression and absorption refrigeration systems. However, in recent years, alternative methods based on adsorption have ...
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A significant portion of energy consumption, particularly during the summer, is attributed to cooling demands in buildings. The most common methods for providing cooling are vapor compression and absorption refrigeration systems. However, in recent years, alternative methods based on adsorption have been explored, and some systems have even reached the commercial market. In Iran, however, such systems have only been investigated at the laboratory level. The goal of this study experimental evaluation of a silica gel–water adsorption cooling system. The constructed system included an adsorbent bed filled with silica gel, a condenser, an evaporator, a heating unit, and a cooling water circulation system. A key feature of this design is the use of a chamber for both the adsorbent bed and the condenser which makes the system simpler. After construction, the system was tested and its performance data were collected. The cooling energy produced at the end of each cycle was measured based on the temperature change in the evaporator. According to the results, the cooling energy per cycle ranged between 1.3 and 1.8 kWh, with a maximum heating energy requirement of approximately 1.8 kWh. Based on various experimental runs, the coefficient of performance (COP) of the system was calculated to be in the range of 0.035 to 0.048. The use of an integrated chamber simplifies the system, but it results in reduced performance.
Systems with Low Energy Consumption
Ahmadreza Keshtkar Ghalati; Mahdieh Ahmadian
Abstract
Light shelves not only create shade but also improve the uniformity of daylight. In addition to saving energy, they can improve the lighting quality of a space. This research aims to position light shelves and deep windows to enhance energy efficiency and daylight illuminance in classrooms in Abadan ...
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Light shelves not only create shade but also improve the uniformity of daylight. In addition to saving energy, they can improve the lighting quality of a space. This research aims to position light shelves and deep windows to enhance energy efficiency and daylight illuminance in classrooms in Abadan (Iran) with hot and dry climates. Rhino/Grasshopper software and Ladybug/Honeybee plugins were used to model and evaluate visual comfort and EUI. By comparing the types of external, internal, and central shelves and in different situations of window depth, the following results were obtained: By combined use of light shelves and deep windows: In central light shelves, energy consumption decreased by 20%, and glare effects were reduced by 53.37%. As a result, installing a window in the depth of the wall did not have much effect on reducing energy consumption, but to some extent, it controlled the intensity of glare. The deep window has reduced energy consumption (13%), and using light shelves has improved energy performance (14 to 20%). Compared to the base model, the combined light shelves reduced UDI by 20% and glare by 53%, while the inside light shelves reduced UDI by 14% and glare by 30%. Therefore, installing light shelves always reduces glare. But if the intention is to save energy, the central and external light shelves in the position of the deep window are very useful.
Systems with Low Energy Consumption
Seyed E. Hoseini; M. Simab; B. Bahmani-Firouzi
Abstract
The argument of power systems planning in home microgrids has become one of the burning topics in optimization studies today among the researchers. Since the installation and use of high-capacity energy sources in power systems have many limitations and constraints, so part of the perspective of power ...
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The argument of power systems planning in home microgrids has become one of the burning topics in optimization studies today among the researchers. Since the installation and use of high-capacity energy sources in power systems have many limitations and constraints, so part of the perspective of power systems studies tends to operate residential microgrids. For this purpose, in this paper, operation planning is based on a residential microgrid consisting of combined heat and power (CHP), heat storage tank and boiler, and when possible, surplus electricity is sold to the upstream network to generate revenue. One of the innovations of this paper is the use of the exergy function to complete the optimization and, in practice, combine energy with economics. Other objective functions of this paper are to discuss the reduction of carbon dioxide in the air and the cost of operation. Energy management and planning in this home microgrid is tested with different capacities and types of CHPs, so that the home operator can choose the best mode to use. The multi-stage decision based dynamic programing (MSD-DP) optimization approach is used to minimize the operation costs of proposed framework. The most important innovation of this paper is the use of exergy function for energy management in a residential complex where CHP can also be used to generate electricity and heat simultaneously. Therefore, determining the capacity of CHP and the possibility of exchanging electricity with the upstream network can be mentioned as other innovations of this research.
Systems with Low Energy Consumption
Seyyed M. Mirlohi; M. Sadeghzadeh; R. Kumar; Mehdi Ghassemieh
Abstract
In this research, a plan to implement a zero-energy building (ZEB) for a hot and dry climate region of Iran (Yazd) is introduced and a comparison with a typical house of that climate is performed. Based on climate conditions, several active or passive methods are available in order to create a balance ...
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In this research, a plan to implement a zero-energy building (ZEB) for a hot and dry climate region of Iran (Yazd) is introduced and a comparison with a typical house of that climate is performed. Based on climate conditions, several active or passive methods are available in order to create a balance between energy supply and demand, namely improving wall insulations by using efficient heating/cooling devices, using solar energy, utilizing energy storage devices, and etc. Here, the SketchUp software is employed to present the plot of the selected building. In addition, one of the interfaces of Energy plus software called "BEOpt" is used for performing energy and economic analyses on the fast-constructed and pre-fabricated schemes. Considering the equipment’s world price, the results demonstrate that the zero-energy building scheme in selected climate conditions is applicable and the payback period is estimated to be about 5.5 years. In addition, replacing the typical buildings with a ZEB will decrease carbon dioxide emissions by about 27.4 metric tons/yr.