• JOURNAL OF ELECTRICAL WORLD
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• s.451
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• pp.22-31
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• 2014

온실가스 다량 배출로 인한 지구온난화 현상은 많은 분야에서의 변화를 요구하고 있다. 특히 온실가스 배출의 주원인으로 꼽히고 있는 발전 등 에너지산업 분야의 경우 그 요구는 매우 거세다. 과거에는 경제성장이라는 측면만 고려하면 됐지만, 지금은 기후변화 대응을 위해 환경을 최우선적으로 고려할 것을 주문하고 있기 때문이다. 문제는 현재 전 세계적으로 약 20%에 이르는 인구가 전기 에너지를 사용하지 못하고 있다는 점이다. 즉 향후 에너지를 사용하고자 하는 신규 소비자는 더욱 늘 것이고, 산업의 발전으로 인한 에너지 소비 역시 큰 폭으로 증가할 수밖에 없다. 문제가 굉장히 어렵지만 해결책도 분명 존재한다. 결론적으로 말해 온실가스 배출을 최소화하면서도 에너지 효율은 높인 기술을 개발하면 되는 것이다. 그리고 이미 세계 각국은 청정에너지 기술개발을 위해 다각도의 노력을 펼치고 있는 상황이다. 그렇다면 세계 각국은 미래 에너지시장을 선도할 청정에너지 기술로 어떤 것을 꼽고 있을까. 이 질문에 대한 대답은 지난 5월 서울에서 개최된 '제5차 클린에너지장관회의(CEM, Clean Energy Ministerial)'에서 제시된 바 있다. CEM은 한국, 미국, 영국, 독일, 중국, 일본 등 세계 에너지의 70%를 사용하는 주요 국가의 관계 장관들이 모여 클린에너지 공급 확대와 에너지효율 향상을 위한 구체적 액션플랜을 논의하는 자리다. 2010년 미국에서 첫 회의가 열렸고 아랍에미리트, 영국, 인도에 이어 한국은 5번째로 CEM을 개최했다. 특히 이번 CEM에서는 회원국들의 의견을 모아 10대 청정에너지 혁신기술을 최초로 선정, 발표했다. CEM은 "향후 10년 간 에너지 시장의 변화를 선도할 유망 기술을 선정한 것으로 IEA 등 국제기구와 주요국 기술 로드맵을 기준으로 해 23개 회원국 회람을 거쳐 최종 확정하게 됐다"고 배경을 설명했다. 이번에 선정된 10대 청정에너지 혁신기술은 ${\triangle}$초고압직류송전 ${\triangle}$에너지저장장치 ${\triangle}$바이오연료 ${\triangle}$마이크로 그리드 ${\triangle}$탄소포집 및 저장 ${\triangle}$초고효율 태양광 발전 ${\triangle}$해상풍력 ${\triangle}$신재생에너지 하이브리드시스템 ${\triangle}$빅데이터 에너지관리시스템 ${\triangle}$지열 시스템이다. 이와 관련해 산업통상자원부 윤상직 장관은 "이번에 선정된 10개의 기술은 최근의 기술적 정책적 추세가 잘 반영된 결과"라고 평가했다. 특히 윤 장관은 "중앙집중형 공급원에서 분산형 전원으로의 변화, 에너지 효율향상의 중요성, ICT와 융 복합 추세 등 우리나라의 상황에서 시사하는 바가 크다"며 "현재 수립하고 있는 '제3차 국가에너지기술 개발계획'에 이러한 기술적 추세를 반영하겠다"는 의사를 표명했다. 향후 10년 간 에너지시장의 변화를 선도할 10대 청정에너지 유망기술을 자세히 소개한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.187-192
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• 2019

Hybrid power storage system with emergency power function for demand management and power outage minimizes the investment cost in the building of buildings and factories requiring emergency power generation facilities, We propose a new business model by developing technology that can secure economical efficiency by reducing power cost at all times. Normally, system power is supplied to load through STS (Static Transfer Switch), and PCS is connected to system in parallel to perform demand management. In order to efficiently operate the electric power through demand forecasting, the EMS issues a charge / discharge command to the ESS as a PMS (Power Management System), and the PMS transmits the command to the PCS controller to operate the system. During the power outage, the STS is rapidly disengaged from the system, and the PCS becomes an independent power supply and can supply constant voltage / constant frequency power to the load side. Therefore, it is possible to secure reliability through verification of actual system linkage and independent operation performance of hybrid ESS, By enabling low-carbon green growth technology to operate in conjunction with an efficient grid, it is possible to improve irregular power quality and contribute to peak load by generating renewable energy through ESS linkage. In addition, the ESS is replacing the frequency follow-up reserve, which is currently under the charge of coal-fired power generation, and thus it is anticipated that the operation cost of the LNG generator with high fuel cost can be reduced.

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.212-222
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• 2000

This study was performed to investigate the performance of heat recovery device attached to exhaust gas flue connected to combustion chamber of greenhouse heating system. The experimental heat recovery system is mainly consisted of LPG combustion chamber and two heat recovery units; unit-A is attached directly to the exhaust gas flue, and unit-B is connected with unit-A. Heat recovery performance was evaluated by estimating total energy amounts by using enthalpy difference between two measurement points together with mass flow rate of gas and/or air passing through each heat recovery unit depending on 5 different flow rates controlled by voltage meter. The results of this experimental study, such as heat exchange behavior of supply air tubes and exhaust air passages crossing the tubes, pressure drop between inlet and outlet, heat recovery performance of exchange unit, etc., will be used as fundamental data for designing optimum heat recovery device to be used for fuel saving purpose by reducing heat loss amounts mostly wasted outside of greenhouse through flue.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.2
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• pp.279-287
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• 2012

Recharging battery in electric vehicle takes a quite long time compared with gasoline and diesel vehicle which is a problem, the industries should solve, to introduce the electric vehicle into the market. For this reason, the institutions are suggesting a method replacing the discharged battery to recharged battery which is recharged in the switching center. However, this technology is still required to make clear the controversial issues such as threats to security and identification of users. In this paper, we explore the factors that threats to securities in battery exchange system and define the security requirements of the battery exchange system to solve suggested issues. The results of the research are expected to be the reference in the other studies of electric vehicle field of the commercialization of the battery recharging methods and analysis of the securities.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.301-301
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• 2010

현재 전 세계는 앞으로 사용 될 대체 에너지에 많은 관심 가지고 있다. 지금 사용하고 있는 에너지 연료는 한정되어 있기 때문에 대체에너지에 대한 연구가 활발히 진행 되고 있다. 그 중 압전체를 이용한 에너지 하베스팅은 많은 주목을 받고 있다. 주변 환경에서 필요한 에너지를 끌어 쓸 수 있는 대표적인 청정에너지 시스템 중 하나이기 때문이다. 최근 전원 공급원으로써 에너지 수확 시스템은 현 사회에 사용되고 있는 배터리로 전원을 사용하는 제품들을 소용량과 저전압 분야에서의 에너지 수확의 원리를 이용하여 전기전자제품의 사용시간 연장 및 응용분야 확대를 시도하는 연구가 활발히 수행되고 있다. 압전세라믹스를 이용한 에너지 하베스팅은 진동에너지를 전기에너지로 변환하는 것으로서 압전 특성이 높아야 한다. 일반적으로 압전 세라믹스는 PbO 성분이 들어가므로 환경적 오염 뿐만 아니라 인체에도 영향이 좋지 않으므로 많은 나라에서 이러한 성분을 제한하고 점차적으로 줄어들고 있는 시점에서 PbO를 사용하지 않고 Lead-Free 세라믹를 사용한 연구가 진행되고 있다. 이 논문에서는 일반적인 소결 방법을 이용하여 (Na,K)NbO3 세라믹에 CeO2를 첨가한 압전 세라믹을 제작하였다. 제작된 압전 세라믹스로 에너지 하베스팅 소자를 제작하고, 이 소자로 수확된 에너지로 DC-DC Converter 응용 특성에 대하서 연구하였다. 압전 세라믹스의 좋은 압전 특성을 출력하기 위하여 캔틸레버의 고유 진동수가 진동원의 주파수와 일치하는 공진을 일으켜야 한다. 따라서 구동회로는 주파수원을 찾아 설계하였고, 압전 세라믹스의 진동은 가진기를 이용하여 구동실험을 하였다. 지금까지 나와있던 에너지 하베스팅 회로와 비교하여 그 특성을 분석하고, 시뮬레이션 및 실험을 통하여 검증하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1225-1234
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• 2013

According to the importance of greenhouse gas emissions, it grows day by day, the goverment is promoting to prepare the specific policy implementation to enhance building energy-saving design standars as the development agenda. In this study, the statistical analysis was performed by Descriptive statistics, Regression analysis, and Hypothesis testing to collect to generate and storage energy usage data in real time to settle parameter setting to affect energy consumption under energy-guzzling apartment not single building. This study is expected to be utilized as the basis for the optimum energy-saving design of the future of the building or facility energy costs rise and the demand for energy-efficient and stable management.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.121-126
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• 2020

In many parts of the world, climate warming has caused tremendous environmental disasters to repeat every year. Overuse of fossil fuels, the main source of energy, has affected the global environment, destroying the global ecosystem and depleting resources. To overcome this, efforts to reduce carbon emissions through the development of renewable energy are being actively studied at home and abroad. Already, new technologies are being reported abroad to reduce carbon emissions. Zero Energy House is a model that reduces low carbon emissions and energy use due to the use of high-density materials for high-heated materials, and can live in real life by receiving the minimum required energy through renewable energy. Although the government is trying to apply this in Korea, it is difficult to become common because of the lack of economic feasibility. The purpose of this study is to study models that can zero carbon emissions, which are eco-friendly elements, secure construction economy of zero energy house by using ventilation system, heat exchanger and energy storage system for public use, and attach automation system to window opening/closing to maintain indoor temperature.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.4
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• pp.647-669
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• 2013

Depletion of fossil fuels and sharp rise of international oil price as well as climate worming and frequent environmental disasters have required to strengthen resource(esp. energy) and environmental policy and discourse. And hence highly influential discourses and policies such as the concept of sustainable development and strategy for carbon regulation have been developed and pursued world-widely. But these concept and strategy have seemed to be subsumed in the process of neoliberalism, so as to have little effective results. This leads us to energy transition and energy autonomy or autarky as alternative strategic and normative concepts. Daegu has shown strong interests in urban energy problems relatively earlier than other cities, and developed the so-call 'Solar City' project. But it could not properly tackled with the problems, while tending to meet with the global imperatives. This paper considers urban energy problems and energy policy of Daegu with its significance and limitations, and suggests 4 principles for urban energy transition and autonomy with some concrete alternative measures; that is, the transition from fossil and nuclear energy to renewable energy, the transition from supply-led policy to demand side focusing policy, the transition from central governing energy system to locally distributed one, and the transition from market-dependent management to citizen-participatory energy governance.

• Journal of Hydrogen and New Energy
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• v.22 no.5
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• pp.625-633
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• 2011

Characteristics of a commercial metal hydride (MH) hydrogen supply system have been investigated and an operating strategy was developed based on the experimental data. As a prior step, charging/discharging capacity, thermal properties such as heat capacity, heat of reaction of MH system were experimentally measured. And then P-C-T data for various operating conditions were collected and a correlation between P, C and T predicting the behavior of MH was derived. Based on the basic experimental data, an operating strategy of MH system was developed, in which the hot water temperature supplied into the water jacket of MH was controlled depending on the pressure of MH, thereby the pressure of MH could be maintained at a suitable range. By adjusting the temperature of hot water from $40^{\circ}C$ to $60^{\circ}C$, the maximum discharging capacity of hydrogen could be increased by 4.7%, and consequently more stable hydrogen supply and longer operation time of fuel cell system could be achieved.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.34-39
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• 2018

Natural gas is attracting attention as an alternative to existing fossil fuels. Natural gas has a high octane number. Therefore, knocking does not occur even if the compression ratio is increased, so that the thermal efficiency and the output can be improved. And it is relatively easy to apply the natural gas supply system to the internal combustion engine hardware system. In this study, a gasoline direct injection turbo engine was converted into a natural gas port injection type turbo engine. Therefore, the combustion and performance of the engine are measured and compared comprehensively in the region where the turbo operates.