• Journal of the Korean Solar Energy Society
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• v.24 no.2
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• pp.33-38
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• 2004

Outside wall systems we lost much energy from the dew of thermal bridge and unsuitable adiabatic construction. The air vent wall system can make reduce cooling loads from the outside wall in summer. The basic concept is connected with buoyant force by the difference of density. An external surface of a wall absorbs solar radiation, and transfers it to the air in the cavity. The warmed air gets buoyant force. So the warmed air is released through the top opening and cooler outside air replaces the space in the cavity. So because of the cavity and the openings, the cooling load reduction by natural ventilation is believed to be considerable. The purpose of this study is finding optimal length of air cavity by numerical analyses.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.111-124
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• 2011

The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight by opening/closing of a blind. In previous researches on blind controls, major problem is that the time interval and amount of blind movement do not meet the control objective at the inflected zone of solar profile curve. To overcome these limitations revealed in theprevious researches, following tasks were performed in this study. i)To establish the control objective to accomplish the goal of this study. ii)To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various solar profile angle curves. This study proposed the control strategy and method that define the base control section implying the inflection point within the control objective zone and subsequently, divide the control sections for the residual time zones. The proposed strategy and method are found to increase the incoming daylight and solar irradiation by 0 to 15 %.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.209-214
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• 2008

Since the direct normal insolation is a main factor for designing any solar thermal power system, it is necessary to evaluate its characteristics all over the country. We have begun collecting direct normal insolation data since December 1992 at 16 different locations and considerable effort has been made for constructing a standard value from measured data at each station. KIER(Korea Institute of Energy Research)'s new data will be extensively used by solar thermal concentrating system users or designers as well as by research institutes. From the results, we can conclude that 1) Yearly mean 2.67 kWh/$m^2$/day of the direct normal insolation was evaluated for all days all over the 16 areas in Korea. 2) All day's direct normal insolation of spring and summer were 2.91 kWh/$m^2$/day and 2.23 kWh/$m^2$/day, and for fall and winter their values were 2.78 kWh/$m^2$/day and 2.77 kWh/$m^2$/day respectively. So, spring, fall and winter were higher, and summer was lower than the yearly mean value

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.31-36
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• 2011

CF(Circular Fresnel) POF(Plastic Optical Fiber) daylighting system is a beam daylighting system utilizing solar direct beam radiation. In this study, a CF POF daylighting system has been introduced, developed and applied to KIER test buildings. The CF POF daylighting system consists of three parts: light collector, light transmitter and light diffuser. The light collector includes a Circular Fresnel lens focusing solar direct illuminance by sun tracking. The light transmitter contains the POF cable which has light transmission loss of 4.5% per meter. The light diffuser has about 80% diffuser efficiency. This study aims to evaluate of POF daylighting system performance. At the results of a CFPOF system performance evaluation, the theoretical CFPOF system efficiency was 41.9% and the actual CFPOF system efficiency at the KIER test building was 37.5%. The difference was due partly to the connecting efficiency.

• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.28-38
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• 2014

The effects of geometric parameters (stack position, stack length, resonator tube length) and varying input power over acoustic energy output were investigated. The acoustic laser kit (Garret 2000) was used for the construction of TA lasers. A series of sound pressure level measurements in different orientations did not differ significantly confirming that the sound wave generated could be assumed as a spherical wave. An increase in acoustic pressure was recorded with respective increase in input power, stack and resonator tube lengths owing to their relative influence over heat transfer rate and critical temperature gradient across the stack.

• Advances in Energy Research
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• v.5 no.2
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• pp.179-205
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• 2017

This research presents an in-depth analysis of location planning of the solar-hydrogen power plants for electricity production in different cities situated in Kerman province of Iran. Ten cities were analyzed in order to select the most suitable location for the construction of a solar-hydrogen power plant utilizing photovoltaic panels. Data envelopment analysis (DEA) methodology was applied to prioritize cities for installing the solar-hydrogen power plant so that one candidate location was selected for each city. Different criteria including population, distance to main road, flood risk, wind speed, sunshine hours, air temperature, humidity, horizontal solar irradiation, dust, and land costare used for the analysis. From the analysis, it is found that among the candidates' cities, the site of Lalezar is ranked as the first priority for the solar-hydrogen system development. A measure of validity is obtained when results of the DEA method are compared with the results of the technique for ordering preference by similarity to ideal solution (TOPSIS). Applying TOPSIS model, it was found that city of Lalezar ranked first, and Rafsanjan gained last priority for installing the solar-hydrogen power plants. Cities of Baft, Sirjan, Kerman, Shahrbabak, Kahnouj, Shahdad, Bam, and Jiroft ranked second to ninth, respectively. The validity of the DEA model is compared with the results of TOPSIS and it is demonstrated that the two methods produced similar results. The solar-hydrogen power plant is considered for installation in the city of Lalezar. It is demonstrated that installation of the proposed solar-hydrogen system in Lalezar can lead to yearly yield of 129 ton-H2 which covers 4.3% of total annual energy demands of the city.

• KIEAE Journal
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• v.12 no.1
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• pp.105-112
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• 2012

When a building is planned and designed, the design should be able to minimize the cost during the whole life cycle of the building. This study has begun to analyze LCC about the alternative design which is applicable to renewable energy facility construction. It is reviewed domestic and foreign papers about the trend of LCC technology and it is determined the analytical method to analyze the LCC of renewable energy. Regarding the review of alternatives, it is chosen the three alternatives which are able to designed combing the renewable energy facilities and it is performed the LCC analysis about each alternative. Alternative 1 is Photovoltaic + Solar Thermal + Photovoltaic /Wind Power, Alternative 2 is Geothermal + Photovoltaic, and Alternative 3 is Photovoltaic + Solar Thermal. The LCC analysis is present value method, its analytical period is 40 years and it is applied 3.2% of real discount rate. As a result, it is proved that Alternative 1 and Alternative 3 are not able to collectible the early investment cost during the analytical period and Alternative 2 is analyzed that its pay-back period of early investment cost is about 31 years. As the final outcome of this study on case analysis, it is more advantageous to use the combination of Geothermal and Photovoltaic energy than to use the other combination in LCC aspect.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.23-30
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• 2011

International cooperation to reduce greenhouse gas emissions is expected to provide a big crisis and a great opportunity at the same time for our industry that heavily consumes energy. To cope actively with the international environmental regulation, such as the Framework Convention on Climate Change, quantitative measurement of the volume of greenhouse gases emitted by various industries and quantitative prediction of the greenhouse gas emissions of the future are becoming more important than anything else at the national level. This study aims to propose the calculation process of carbon dioxide($CO_2$) emission for building in life cycle. This paper describes and compares 9 different tool for environmental load estimation with LCA. This study proposed the calculation process for quantitatively predicting and assessing $CO_2$ emissions during the life cycle of buildings based on the life cycle assessment(LCA). The life cycle steps of buildings were divided into the design/supervision, new construction, repair, renovation, use of operating energy in buildings, maintenance, and reconstruction stage in the life cycle inventory analysis and the method of assessing the environmental load in each stage was proposed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.69-73
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• 2007

As the interest in environmental pollution increases, the use of renewable energy is uprising. Among the renewable energy resources, wind and solar energy have no environmental impact and they can be used as unlimited resources. The two power systems are mutual supplementary systems. So the two systems are usually combined for generation. We have measured several data about wind and solar. These data can be used the foundation data for the construction of wind and solar power generation plants. Also we analyzed the possible optimal solar power system for 10[kW] wind power.

• Journal of the Korean Solar Energy Society
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• v.38 no.4
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• pp.33-42
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• 2018

In the application of the BIPV system, it is expected that the workability is lowered due to the difficulty in securing the space for wiring in the frame and the performance of the frame due to the wiring hole processing is lowered. Therefore, In this study, we propose a method to improve the wiring of the inner space of the BIPV frame, and through the simulation evaluation process, the thermal and condensation performance are secured by complementing the problems caused by the hole machining, and the time and effort required for BIPV construction are reduced. For this purpose, a wiring treatment method using a flange insertion tube was proposed, and the thermal and condensation performance was evaluated through simulation analysis.