• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.10 no.2
• /
• pp.7-12
• /
• 2014

Government has recently restricted heating and cooling set temperatures for the commercial and public buildings due to increasing national energy consumption. The goal of this paper is to visualize a future two way indoor set temperature control impact on building energy consumption by using TRNSYS simulation modeling. The building was modelled based on the twin test cell with the same dimension. Air source ground coupled heat pump performance data has been used for modeling by TRNSYS 17. Daejeon weather data has been used from Korea Solar Energy Society. The heating set temperature in the reference room is $24^{\circ}C$ as well as the target room set temperature are $23^{\circ}C$, $22^{\circ}C$, $21^{\circ}C$ and $20^{\circ}C$. The cooling set temperature of the reference room is also $24^{\circ}C$ as well as the target room set temperature of $25^{\circ}C$, $26^{\circ}C$, $27^{\circ}C$ and $28^{\circ}C$. For the air source heat pump system, heating season energy consumption is $35.52kWh/m^2y$ in the reference room. But the heating energy consumption in the target room is reduced to 7.5% whenever the set temperature decreased every $1^{\circ}C$. The cooling energy consumption in the reference room is $4.57kWh/m^2y$. On the other hand, the energy consumption in the target room is reduced to 22% whenever the set temperature increased every $1^{\circ}C$ by two way controller. For the geothermal heat pump system, heating energy consumption in the reference room is reduced to 20.7%. The target room heating energy consumption is reduced to 32.6% when the set temperature is $22^{\circ}C$. The energy consumption in the target room is reduced to 59.5% when the set temperature is $26^{\circ}C$.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1220-1221
• /
• 2007

Building-integrated photovoltaic(BIPV) perform traditional architectural function of walls and roof while also generating electricity. But most of the absorbed solar energy appears passively as heat, raising the temperature of cells and reducing the efficiency with which the active part is converted into electricity. Therefore this paper presents the comparison of electrical, architectural and thermal performance of roof integrated photovoltaic(PV) modules, which is composed of different hybrid structure layer such as urethane form, waffle stud etc.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.17 no.4
• /
• pp.370-376
• /
• 2005

For the purpose of investigating the effective removal of heating/cooling load from light-weighted building envelope, two air-conditioning systems, conventional parameter air-conditioning system and air-barrier system, are evaluated and compared by both experiment and simulation with six different cases during heating and cooling season. In addition, the characteristics of window-side building thermal load are assessed by varying supply air velocity in order to seek the optimal system operation condition. The results are as follows. 1) Air-barrier system is more effective to remove heating/cooling load at perimeter zone than conventional parameter air-conditioning system. Moreover, the better effectiveness appears during cooling season than during heating season. 2) The experiment during cooling season provides that indoor temperature of air-barrier system shows $1^{\circ}C$ less than that of the conventional system with similar outdoor air temperature profile, and indoor temperature distribution is more uniform throughout the experimented model space. It concludes that air-barrier system can achieve energy saving comparing to the conventional system. 3) The capturing efficiency of air-barrier system is 0.47 on heating season and 0.2 on cooling season with the same supply air volume. It results that the system performs effectively to remove building thermal load, moreover demonstrates high efficiency during cooling season. 4) The simulation results provide that capturing efficiency to evaluate the effective removal of building load from perimeter zone shows high value when supply air velocity is 1 m/s.

• Journal of the Korean Institute of Rural Architecture
• /
• v.26 no.2
• /
• pp.1-8
• /
• 2024

Carbon neutrality refers to a state in which there is no global increase in CO₂ emissions due to human activities. In Korea, for carbon neutrality, green remodeling of existing buildings and customized support tasks for zero energy in new buildings are presented. Germany is showing fundamental changes in energy supply, such as applying renewable energy and higher energy efficiency from nuclear and fossil fuels, which were the existing energy sources. In this study, how Germany establishes policies for carbon neutrality at each state level and the cases applied to increase the energy efficiency of the actually applied residential complexes are analyzed based on this. As a result of the case complex analysis, it was found that the construction direction was being promoted as a zero-energy complex or a carbon-neutral complex by gradually reducing the energy demand in buildings and supplying additional energy with new and renewable energy in the low-energy building distribution in the 1990s. In Germany's ecological complex, energy standards have been strengthened from low-energy architecture to plus-energy architecture over time, and annual heating energy consumption standards and heat transmittance rates for each structure have been achieved at a higher level. The results of this analysis will serve as basic data and derivation of applicable items when planning residential complex development and remodeling of existing buildings for the domestic carbon-neutral goal in the future.

• 한국태양에너지학회:학술대회논문집
• /
• 2008.11a
• /
• pp.263-268
• /
• 2008

In a residential complex case, the efficiency of land use are maximized, but a variation of external condition such as load in-equality, the increase in wind velocity and solar radiation by a height causes increasing energy in a building. Besides, because of increasing window size for a lighting and a view, it comes heating load in winter and cooling load in summer. A choice of cooling-system is important for this reason. Recently an internal high-rise residential complex installs an air-cooling system and operates individual heating. However, this study applies water-cooling used one public cooling-tower instead of an air-cooling system, also with an efficiency test of an air and a water-cooling system, consider an internal applicability.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.1373-1378
• /
• 2009

This study is aiming comparison and analization between efficiency of hybride air conditioning system which uses low temperature water under dam and air and EHP(Electric Heat Pump). The experimental was carried out with air cooling tests for EHP system having 80HP and composition heat pump system. P-i diagram of both systems and COP was used to derive schemetic and calcuations. As results of the tests, hybride system has 1.4 time higher efficiency coefficient.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.265-266
• /
• 2008

The interest on harmonics which is one of the matters related with power quality problem is not limited in only the system where the large scale industrial load is connected. The harmonics phenomenon not only causes the malfunction of devices, but also lowers the energy efficiency of power system. This paper focuses on the harmonic analysis process to establish the harmonic mitigation method, considering the harmonics distortion as a major cause to reduce the energy efficiency of a skyscraper. A system diagram of building is modelled with PSCAD simulator. Based on the harmonic analysis results of it, the electrical locations with the high priority to install the mitigating devices are selected. Finally, the result of PSCAD simulations and the site-measured data are compared, verifying that they reach a common conclusion.

• Journal of the Korean Solar Energy Society
• /
• v.34 no.5
• /
• pp.109-115
• /
• 2014

The supply rate of renewable energy has been increasing under the influence of an energy scarcity. Government has supported the use of renewable energy by government subsidies. The operation of renewable may not been operating appropriately, although increasing the use of renewable energy. We found out some problems of the operation of renewable energy and offered some improvements. This research proposes the efficient operation method for the solar thermal system, and proposed operation method was compared and evaluated with existing operation strategy after selecting one building installed solar thermal system. Recently, the interest to renewable energy has increased because of the environmental issues and energy crisis. However the utilization of the renewable energy system is low because of the use of renewable energy system and existing renewable energy system independently, although supply rate of renewable system is increasing. Especially, in the case of solar thermal system heating load is not responsible for the load of hot water supply in many cases. Therefore, suggesting efficient operation plans and evaluations of the energy consumption and efficiency of a solar thermal system is needed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.21 no.7
• /
• pp.417-423
• /
• 2009

Air curtains are widely used for gates of shopping mall, warehouse, cold stores and refrigerated display cabinets. The purpose of the air curtain is to reduce the infiltration of outdoor air and heat loss from the air conditioning space to ambient air. Design data for the air curtain given by previous researchers do not mention the influence of wind speed. Thus, this paper presents a performance of single jet air curtain in heating space when the wind blows toward the opening space of the building. A numerical simulation is used to study the influence of various parameters on the efficiency of the downward-blowing air curtain device which is installed inside of the wall above the door. The performance of the air curtain is evaluated by sealing efficiency which provides the assessment of the energy savings. A new safety factor is also proposed for determination of air curtain jet velocity under the various wind conditions.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.57
• /
• pp.305-331
• /
• 2013

The purpose of this study aims to the improvement prospect of green insurance industry in Korea. Green insurance includes all classes of general insurance business including unoccupied property insurance and empty building insurance, business insurance, personal insurance, etc. Green policies often cover expensive systems that are not covered under most property policies. The same is true for some underground property, which is also exempted from many property policies. At least insurers already offer products designed to fund rebuilding damaged properties to meet certain environmental and building standards. While the products are in their infancy, insurers and brokers say the huge interest in environmental issues will increase demand. Green buildings that improve energy efficiency and air quality and reduce waste are designed to reduce their effects on the environment and the health of building occupants. Buildings account for 39% of U.S. carbon dioxide emissions, according to the Department of Energy. Insurers say that, as sustainable buildings become more common, green insurance will become more popular and some of its features might become a standard part of property policies.