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AbstrctThis study is aimed at analyzing the impact of effective shading design for office buildings. For shade design, the overheated period for the area in which a target building was located was estimated, the building was configured to be shaded during this period, and a different shading design was applied for each direction. Using this shade design, the daylighting performance and the reduction in cooling loads during the overheated period were evaluated. The daylighting performance was evaluated by employing the daylight factor and useful daylight illuminance (UDI). The results showed a 35% reduction in cooling loads due to the shading device. Regarding the daylight factor, more points were included in a proper daylight factor of 2–5%, which was shown to increase the UDI to 500–2,000 lux.

AbstrctThere is a growing interest in sustainable design in the building industry to reduce energy consumption and minimize adverse environmental impacts of buildings. The strategies for sustainable design are as follows: 1) reducing the size of the building′s equipment system and saving energy through an optimal design; 2) maximizing natural energy use through a passive solar heating system; and 3) utilizing an active system through applications of high-performance heating, ventilation, and air conditioning (HVAC) and lighting systems, installation of new and renewable energy facilities, and so on. It is vital to evaluate and compare the energy efficiencies of design alternatives at an early design stage, and hence, to improve the energy performance of the final building, as design elements determined at an early phase in the architectural design process greatly influence the energy performance of the building itself. Further, costs increase over time with the number of design changes made. In the course of this research, the KLT (Korean lighting and thermal energy) method was revised and developed based on the lighting and thermal energy (LT) method, adjusting for South Korea′s climate and architectural regulations, which can be used to assess the energy performance of buildings. This study was conducted to determine the process of selecting optimal design alternatives to maximize building energy performance at an early stage in the process.

A comfortable outdoor environment can be achieved through well-designed physical planning, which includes the layouts of buildings, covering materials, grass, trees, water areas, etc. In this study, the outdoor environments of an apartment complex were measured quantitatively. The paving, grass and water areas were chosen to analyse the effects of ground cover on the outdoor environment. An unsteady-state computational fluid dynamics (CFD) simulation was also conducted with the same conditions as the measurement. In order to obtain the reliability and limitation of the simulation, the results of the measurement and the simulation were compared. The effects of changing the green area, including the grass and the trees, to 15% and 50% were analysed by the simulation method.Depending on the ground cover, the air temperature slightly changed. However, the mean radiant temperature (MRT) of the grass area was lower than that of other areas. Especially the shaded area showed a very low MRT and thus thermal comfort was improved. Because over 75% of MRT was produced by long wave radiation, increasing the green area and reducing surface temperature were reasonable methods to improve the outdoor thermal environment.

Each country is giving number one priority to reduction of building energy consumption to reduce national CO2emissions. Korea has begun to regulate new building's energy performance since 2009, targeting zero energy in 2025. To achieve this goal, the government set goals for each stage, but there has been any concrete model suggested. Thus, this study is to suggest a concrete, feasible residential building model through planning, construction, and performance test of low-energy experimental housing having four stages of 40%, 60%, 80%, and 100% energy consumption reduction compared to existing housing. This study selected apartments suitable for the situation in Korea by reviewing domestic and overseas experimental housings, and predicted performance standards, planning of technology application, and according energy performance for four experimental houses. As a result of progressively improving the performance of building envelopes and ventilation and applying high-efficiency system, 100% reduction model's energy demand has decreased by about 43% compared to base model. The remaining 57% includes hot water supply, home appliances, and cooking which are hard to be reduced, and net zero energy house turned out achievable by applying 12.5% of solar heat, 7.5% of geothermal heat, and 37.0% of photovoltaics.

abstractThe purpose of this study was to propose a building energy management process, verify the proposed model by applying energy management techniques in a real office building, and develop an empirical approach for predicting building energy use with regression analysis. This study proposed the four major energy management steps: energy audit, energy analysis, identifying and evaluating the energy saving opportunities, and retrofit implementation and follow-through. For the prediction of energy use, simple regression models were developed based on historical energy consumption data as a function of daily outside temperatures, while the predicting equations were derived for different operational modes and day types. By selecting a real building as a case study, the feasibilities of the building energy management process and the empirical approach for predicting building energy use have been examined.

AbstractThe housing market in Korea is changing rapidly. As multi-functional high-rise residential complexes become popular, occupants need more comfortable indoor environment as well as more usable spaces than ever before. These trends force to increase the energy usage for environmental controls, especially for cooling. Thus, this study aims at reducing the cooling energy requirements of high-rise residential complex by maximizing the possibilities of natural ventilation strategies through cross ventilated Double Skin Façade. Based on ESP-r simulations, it was confirmed that the Double Skin Façade could reduce up to 30~40% of cooling energy compared to the conventional façade designs.

LCC (Life Cycle Cost) analysis is a practical method and a guideline for evaluating the economic performance of building service systems. By using the LCC analysis, the most cost-effective design decision can be made, which has the lowest LCC during the project study period among the various design alternatives. The present case shows an example of appropriate use of the LCC analysis, by demonstrating the procedures of decision-making among alternative building HVAC systems at Community Center and Congress Hall of a Local Government.