• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1996년도 추계학술발표회논문집(2)
• /
• pp.669-674
• /
• 1996

The theory of quantum mechanics states that for any system there are a set of discrete physical states, quantum states, which corresponds a particular energy level of the system. The lowest energy the system can have, corresponding to its ground state, is not necessarily zero, but depends only on the precise microscopic nature of the system under consideration. At the absolute zero of temperature all systems will be in their lowest energy state (zero point energy) and as the system is warmed from OK, the higher energy states become occupied. The probability of occupancy of the excited states relative to that of the ground state is proportional to the absolute temperature. Therefore we can obtain nuclear dipole and quadrupole moment very accurately at ultra low temperature (<15mk) by NMR and from the destruction of anisotropy. The former is called LTNO/NMR and the latter is called LTNO (Low Temperature Nuclear Orientation). In this paper we discuss and introduce only an experimental apparatus with results of cooling power test, a helium dilution refrigerator, which can reache 8mK, and an actual technique for the experiment, a theory and results will be presented in another papers.

• 한국인터넷방송통신학회논문지
• /
• 제20권5호
• /
• pp.121-126
• /
• 2020

지구촌 곳곳에서 기후 온난화로 인하여 엄청난 환경적 재난이 매년 되풀이되고 있다. 에너지의 주공급원인 화석연료 과다 사용으로 지구 환경변화에 영향을 끼쳐 지구 생태계를 파괴하고 자원을 고갈시키고 있다. 이를 극복하기 위해서 신재생에너지의 개발을 통하여 탄소 배출량을 줄이려는 노력이 국내외적으로 활발히 연구되고 있는 게 현실이다. 이미 해외에서는 탄소 배출량을 줄이려는 신기술들이 심심치 않게 보도되고 있다. 제로 에너지 하우스는 고단열재 고기밀성 재료사용으로 저탄소 배출 및 에너지 사용량을 줄어들게 하고 최소한의 요구하는 에너지는 신재생에너지를 통해 공급받아 실거주가 가능한 모델이다. 이를 국내에서도 적용하려 노력 중이나 경제성이 떨어지기 때문에 보편화 되기는 어려운 실정이다. 본 연구의 목적은 친환경적 요소인 탄소 배출을 제로화 하고, 환기 시스템과 열교환기 및 에너지 저장장치를 공용으로 사용하여 제로 에너지 하우스의 시공 경제성을 확보하고, 창호 개방/폐쇠에 자동화 시스템을 부착하여 실내 적정온도 유지가 가능한 모델을 연구하고자 한다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 제40회 하계학술대회
• /
• pp.2184_2185
• /
• 2009

오늘날 세계 여러 국가에서 에너지 소비 절감에 대한 관심이 증가하고 있는 추세이며 특히 국가 전체 에너지 소비량중 상당량을 차지하는 건물에서의 에너지 절감에 대해 많은 관심이 집중 되고 있다. 본 논문에서는 건물 특히 주택에서의 에너지 절감 대안중 하나인 Zero Enegy House에 대해 알아보고 설계시 고려사항 및 효율적인 운영을 위한 가정용 에너지관리프로그램 및 시스템을 제안하고자 하였다.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
• /
• pp.199.1-199.1
• /
• 2010

The purpose of this study is on the thermal performance evaluation of KIER Zero Energy Solar House-II, called ZeSH-II which can be sustained with the support of a very few energy. This ZeSH-II was designed and constructed in the end of 2009 to develop for the goal of 70% self-sufficiency. Several key technologies like as the super insulation, high performance window, wast heat recovery system as well as solar power and thermal system and geo-source heat pump wear used for this ZeSH-II. The monitering of ZeSH-II was conducted for six months from November 2009 to April 2010. The monthly energy consumption was calculated based on the monitering results. As a result, the ZeSH-II shows that the energy self-sufficiency during six months(from oct. to apr.) is about 80% which is higher than that of the target.

• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
• /
• pp.451-456
• /
• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000 kacal/hr, a evacuated tubular solar collector 3.74 $m^2$ of aperture area at the $20^{\circ}$ install angle, a 0.3 $m^3$ hot water storage tank, a 0.15 $m^3$ hot water storage tank for space heating. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• 한국태양에너지학회 논문집
• /
• 제39권5호
• /
• pp.53-63
• /
• 2019

This paper in order to efficiently operate zero energy buildings developed a methodology for optimal operation of PV + ESS active systems. This program consists of three steps. First step is PV optimal operation and second step is PV + ESS optimal operation. Third step is the analysis of the results by PV + ESS optimal operation. The optimal operation of PV + ESS was calculated by using Dynamic Programming (DP). Therefore, the optimal capacity and operating plan of PV + ESS in this study are calculated for electric load at building. This paper conducted case study to verify the validity of the developed algorithm. Also, the sensitivity analysis analyzed the effect of each variable on the optimal operation.

• 한국태양에너지학회 논문집
• /
• 제29권2호
• /
• pp.62-69
• /
• 2009

To reduce the building energy consumption, the major advanced nations are conducting actively many researches on so called a "self-sufficient building(or other words zero energy building)" which can support its required energy by itself. Given this background, KIER(Korea Institute of Energy Research) built full size test-bed of the zero energy solar house in early 2001, and has studied on the self-sufficient heating load up to now. We analyse the sensitivity between the heating load and the solar radiation gain according to the change the effective transmittance of windows. The authors classified 9 cases by solar transmittance of glass. The results demonstrate the solar radiation amount is 0.466 MWh from the eastern zone of Fl.,1(the first floor), 0.332 MWh from Fl.,2(the second floor), 1.194 MWh form the southern zone of F1., and 0.822 MWh from the southern zone of Fl.,2 on the case 1(each cases are classified by window types). On the case 9, the solar radiation amount is 3.127 MWh, 2.662 MWh, 8.799 MWh and 6.078 MWh from the same condition. For the Fl.,1, the amount of Heat Load that is saved per year ranged 10.5 to 48%, and the reduction was anywhere from 0.2 to 17.9% for Fl.,2.

• 한국태양에너지학회 논문집
• /
• 제38권4호
• /
• pp.55-66
• /
• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• 한국태양에너지학회 논문집
• /
• 제40권3호
• /
• pp.21-31
• /
• 2020

The government mandates gradually zero energy building and Photovoltaic power generation systems installed in buildings are emerging as the most realistic alternative to increase the independence rate of building energy. In this study, we propose a method to reduce the power consumption of households by increasing the PV capacity of balconies and applying the method used the charged electric power stored in batteries after sunset. In order to evaluate the electric power energy savings of the residential BESS, a balcony PV 1.2 kW and a battery pack 2 kWh were installed for 9 houses in 4 apartments in Seoul and Gyeonggi-do. The BESS is charged when the balcony PV is generated electric power, and when solar power generation is finished, it supplies power to the electric appliances connected to the load. As a result of installing the solar PV module 1.2 kW and 2 kWh class BESS for 3 households located in Seoul and Gyeonggi-do, the average electric power consumption saving rate was 40%. The reduction in electricity consumption in the case of zero generation surplus power by maximizing the utilization rate of BESS has been improved to about 53%. Therefore, in order to increase the self-sufficiency rate of electric energy in apartment houses, it is effective to increase the solar photovoltaic capacity of the balcony and apply the residential BESS. In the future, it is believed that the balcony PV and home BESS will play a key role in achieving mandatory zero-energy housing.

• 전기전자학회논문지
• /
• 제25권1호
• /
• pp.206-211
• /
• 2021

본 논문에서는 열전에너지 하베스팅을 위한 자가 리셋(self-reset) 기능을 갖는 영점 전류 스위칭(Zero-Current Switching) 회로를 제안한다. 본 논문에서 제안하는 영점 전류 스위칭 회로는 전압비교기 회로에 자가 리셋 기능을 추가하여 전압비교기의 동작전류를 최소화함으로써 에너지 하베스팅 회로의 전력 소비를 줄이고 에너지 변환 효율을 향상시킬 수 있게 한다. 회로 시뮬레이션으로 본 논문에서 제안하는 영전 전류 스위칭 회로의 동작을 검증하고 성능을 평가한 결과, 열전에너지 하베스팅 회로의 출력전압-입력전압 비가 5.5 일 때, 기존의 영점 전류 스위칭 회로를 이용한 하베스팅 회로와의 비교를 통해서 본 논문의 하베스팅 회로의 전력효율이 3.4% 개선되는 것으로 평가된다. 본 논문에서 제안하는 영점 전류 스위칭 회로는 열전에너지 하베스팅의 응용 중에서 특히 저전력과 고에너지 효율 특성이 중요한 웨어러블, 바이오 헬스 관련된 하베스팅 회로의 성능 개선에 기여할 수 있을 것으로 생각된다.