• Journal of the Korean Solar Energy Society
• /
• v.34 no.3
• /
• pp.75-81
• /
• 2014

Recently, the use of renewable energy has been attracted due to the interest in energy-saving and the reduction of CO2 emission. In order to reduce the energy consumption of the cooling and the heating in the field of the architectural engineering, heat pump systems using renewable energy have been developed and used in various applications. In many researches, integrated heat pump systems are suggested which use solar and geothermal heat as the heat source for cooling and heating. However, it is still difficult to predict the performance of the systems, because the characteristic of heat exchange in each system is complicated and various. In this system, the performance prediction simulation of the heat pump was developed using a dynamic simulation model. This paper describes the summary of the suggested systems and the result of the simulation. The average temperature of the heat source, heating loads and COP were calculated with the cases of different local conditions, different system composition and different operation time by TRNSYS 17.

• Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
• /
• v.12 no.6
• /
• pp.557-566
• /
• 2018

The ZEB certification system has come into effect since 2018 according to the ZEB road map. From 2020, the public buildings with the total floor area smaller than $3000m^2$ are the target of the certification, and it will be extended to the buildings with up to $5000m^2$ floor area in 2025. However, current mandatory regulations for public office buildings seem already to meet the ZEB certification system planned for 2025. In this work, two buildings belong to $3,000{\sim}5,000m^2$ in total floor area were selected to analyze the possibility of meeting the ZEB certification only by following current obligation regulations. Results showed that the test buildings satisfied the minimum building energy efficiency and energy self-sufficiency rates for the ZEB certification when the mandatory insulation and installation ratio of renewable energy are applied. This can be useful for revising the road map or extending the target buildings of the ZEB certification.

• Journal of the Korean Solar Energy Society
• /
• v.34 no.2
• /
• pp.53-59
• /
• 2014

Ice Rink is energy intensive building type. Concern of energy saving from buildings is one of very important issues nowadays. New and renewable energy sources for buildings are especially important when we concern about energy supply for buildings. Among new and renewable energy sources, use of seawater for heating and cooling is an emerging issue for energy conscious building design. The options of energy use from sea water heat sources are using deep sea water for direct cooling with heat exchange facilities, and using surface layer water with heat pump systems. In this study, energy consumptions for an Ice Rink building are analyzed according to the heat sources of air-conditioning systems; existing system and sea water heat source system, in a coastal city, Kangnung. The location of the city Kangnung is good for using both deep sea water which is constant temperature throughout the year less than $2^{\circ}C$, and surface layer water which should be accompanied with heat pump systems. The result shows that using sea water from 200m and 30m under sea lever can save annual energy consumption about 33% of original system and about 10% of that using seawater from 0m depth. Annual energy consumption is similar between the systems with seawater from 200m and 30m. Although the amount of energy saving in summer of the system with 200m depth is higher than that with 30m depth, the requirement of energy in winter of the system with 200m depth is bigger than that with 30m depth.

• Smart Media Journal
• /
• v.9 no.1
• /
• pp.84-91
• /
• 2020

Along with increasing the renewable energy utilization, many researches have paid attention on the utilization and efficiency of energy storage systems. Especially, it is required an operational model in order to actively respond with each system's failure of sub-systems in the solar energy storage system. This paper proposes an energy management scheme by estimating the newly generated power based on the solar power generation samples. With comparing the estimated battery charging power in real time and the total charging power of the battery rack, a charge model is applied to adjust the charging power, As a result, the stability of energy storage system would be improved by suppressing the battery heat while maintaining battery C-Rate.

• Journal of the Korean Institute of Educational Facilities
• /
• v.20 no.2
• /
• pp.25-32
• /
• 2013

The purpose of this study is to analyze the state-of-the-art solar energy system design cases among LEED(Leadership in Energy and Environmental Design) certified school projects and to explore the feasibilities for their applications in domestic school design. Investigating the sold wattages in some kinds of buildings, the wattages per an educational facility is the second-largest after that per an industrial facility. That shows that our attention should be actively directed to the utilization of New and Renewable Energy in school facilities. Therefore photovoltaics systems, lighting systems and solarthermal facilities of solar energy systems were analyzed in the LEED cases. Findings demonstrate that applications of solar energy systems in K-12 educational facilities have been executed more than those in higher educational facilities. However, K-12 educational facilities and higher educational facilities by private funds are not categorized as Green Buildings by Support for Making Green Buildings Act. That fact is needed to be amended. Besides that, design developments are needed for building integrated photovoltaics systems and solarthermal facilities in domestic educational facilities.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.12
• /
• pp.1231-1236
• /
• 2016

Paris Agreement signed in January 2015 is a new rule that will replace the existing Kyoto Protocol. The new agreement needs new demands and challenges to minimize carbon emissions. Especially, even though agricultural sector occupies only 1.8% in the national energy consumption, the portion of the energy being occupied in agricultural production costs very high. Although renewable energy and energy-saving facilities is being developed and disseminated for replacing fossil fuel energy and saving energy, the installation-rate is not enough high. Thus, this paper developed Korean-style smart farm system, and carried out the experiment to show the performance of energy savings through analyzing proper environment in domestic situation.

• Journal of Platform Technology
• /
• v.6 no.3
• /
• pp.38-46
• /
• 2018

Smart Grid is an intelligent power grid for efficiently producing and consuming electricity through bi-directional communication between power producers and consumers. As renewable energy develops, the share of renewable energy in the smart grid is increasing. Renewable energy has a problem that it differs from existing power generation methods that can predict and control power generation because the power generation changes in real time. Applying a self-adaptative framework to the Smart Grid will enable efficient operation of the Smart Grid by adapting to the amount of renewable energy power generated in real time. In this paper, we assume that smart villages equipped with photovoltaic power generation facilities are installed, and apply the self-adaptative framework, AiTES, to show that smart grid can be efficiently operated through self adaptation framework.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.06a
• /
• pp.188-191
• /
• 2009

제3차 신재생에너지 기본 계획에서는 기존의 태양광10만호 보급사업을 확대하여 모든 가능한 신재생에너지 부존자원을 최대한 활용하는 통합형 보급 사업으로서의 "2020 그린홈(Green Home) 100만호 사업"이 새로이 추진 중에 있다. 이 사업의 핵심 내용으로는 수요자중심의 맞춤형 주택공급과 이로 인한 민간시장의 활성화, 그리고 하이브리드형 신재생 에너지 시스템 개발 등을 꼽을 수 있다. 본 연구는 지난 "1-2차 신재생 에너지 기술개발 및 이용 보급 기본 계획"에서 추진된 주택용 신 재생에너지 보급 정책 결과와 일본, 독일 등의 해외사례 연구를 바탕으로 현재 시행중인 제 3차 기본계획 추진 과정을 검토하여 다음과 같은 제언을 하고 있다. 즉, 향후 신재생에너지 주택보급 사업의 원활한 수행을 위해서는 치밀한 준비를 통해 사업을 내실있게 추진해야 하고, 계획된 예산을 안정적으로 확보하고 효율적으로 배분하여 사업에 대한 신뢰성을 확보해야 한다. 또한 합리적인 목표 설정을 통해 체계적인 보급 정책을 추진해야 하고, 기술개발과 보급 양 부문에 대한 적절한 균형을 도모해야 한다.

• Journal of Power Electronics
• /
• v.15 no.4
• /
• pp.899-909
• /
• 2015

A dual-input boost-buck converter with coupled inductors (DIBBC-CI) is proposed as a thermoelectric generator (TEG) power conditioner with a wide input voltage range. The DIBBC-CI is built by cascading two boost cells and a buck cell with shared inverse coupled filter inductors. Low current ripple on both sides of the TEG and the battery are achieved. Reduced size and power losses of the filter inductors are benefited from the DC magnetic flux cancellation in the inductor core, leading to high efficiency and high power density. The operational principle, impact of coupled inductors, and design considerations for the proposed converter are analyzed in detail. Distributed maximum power point tracking, battery charging, and output control are implemented using a competitive logic to ensure seamless switching among operational modes. Both the simulation and experimental results verify the feasibility of the proposed topology and control.

• Journal of Climate Change Research
• /
• v.8 no.4
• /
• pp.377-384
• /
• 2017

Amid growing concerns about energy security, energy prices, economic competitiveness, and climate change, district heating (DH) system has been recognized for its significant benefits and the part it can play in efficiently meeting society's growing energy demands while reducing environmental impacts. Policy makers often need to quantify the fuel and carbon dioxide ($CO_2$) emissions savings of DH system compared to conventional individual heating (IH) system in order to estimate its actual emissions reductions. The objective of this paper is to calculate energy efficiency and $CO_2$ emissions saving, and to propose the future direction for DH system in Korea. DH system achieved total system efficiencies of 67.9% compared to 54.1% for IH system in 2015. DH system reduced $CO_2$ emissions by $381,311ton-CO_2$ (4.1%) compared to IH system. The results suggest that DH system is more preferred than IH system using natural gas. In Korea, the aim is to reduce dependence on fossil fuels and to use energy more efficiently. DH system have significant potential with regard to achieving this aim, because DH system are already integrated with power generation in the electricity since combined heating and power (CHP) are used for heat supply. Although the future conditions for DH may look promising, the current DH system in Korea must be enhanced in order to handle future competition. Thus, the next DH system must be integrated with multiple renewable energy and waste heat energy sources.