• 제목/요약/키워드: Renewable energy plant

검색결과 466건 처리시간 0.029초

순환유동층 반응기내 바이오매스의 급속열분해 공정해석에 관한 수치해석적 연구 (Numerical Study on the Process Analysis of Biomass Fast Pyrolysis in a Circulating Fluidized Bed)

  • 이유리;박훈채;최명규;최항석
    • 한국폐기물자원순환학회지
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    • 제34권5호
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    • pp.518-527
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    • 2017
  • The development of renewable energy is currently strongly required to address environmental problems such as global warming. In particular, biomass is highlighted due to its advantages. When using biomass as an energy source, the conversion process is essential. Fast pyrolysis, which is a thermochemical conversion method, is a known method of producing bio-oil. Therefore, various studies were conducted with fast pyrolysis. Most studies were conducted under a lab-scale process. Hence, scaling up is required for commercialization. However, it is difficult to find studies that address the process analysis, even though this is essential for developing a scaled-up plant. Hence, the present study carries out the process analysis of biomass pyrolysis. The fast pyrolysis system includes a biomass feeder, fast pyrolyzer, cyclone, condenser, and electrostatic precipitator (ESP). A two-stage, semi-global reaction mechanism was applied to simulate the fast pyrolysis reaction and a circulating fluidized bed reactor was selected as the fast pyrolyzer. All the equipment in the process was modeled based on heat and mass balance equations. In this study, process analysis was conducted with various reaction temperatures and residence times. The two-stage, semi-global reaction mechanism for circulating fluidized-bed reactor can be applied to simulate a scaled-up plant.

원자력발전소 사고 사망의 통계적 생명가치와 사회적 비용 및 에너지정책 시사점 (The Value of a Statistical Life and Social Costs of Death due to Nuclear Power Plant Accidents and Energy Policy Implications)

  • 김용주
    • 한국방사선학회논문지
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    • 제17권1호
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    • pp.79-90
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    • 2023
  • 본 논문은 원자력발전소(원전) 사고에 의한 조기사망의 사회적 비용을 추정하기 위해 조건부가치측정법(Contingent Valuation Method, CVM)을 이용하여 통계적 생명가치(Value of a Statistical Life, VSL)를 추정한다. VSL 추정치는 약 35억 5천만 원이다. 이에 세계 원전 역사상 발생한 모든 사고 사망자수 약 181만 명을 곱하여 추정한 사회적 비용은 1,952조 원으로서 한국의 2022년 실질 GDP에 비견되는 수준이다. 연평균 조기사망자수와 사회적 비용은 각각 26,000명과 28조 원이다. 1987~2021년간 세계 화력발전소의 사고와 대기오염물질 배출로 인해 발생한 조기사망의 사회적 비용 추정치는 26,919조 원인데, 이는 미국의 2021년 GDP 규모에 상당하는 규모로서 9조 원을 기록한 원전의 약 3,000배에 달한다. 2021년 한 해만 보더라도, 화력발전소의 사회적 비용은 1,075조 원에 달하지만, 원전은 2,920억 원에 불과하다. 한국의 경우, 2050 탄소중립 정책의 영향으로 재생에너지 발전 비중이 증가할 것이므로, 화력발전 대비 원자력발전 비중을 증가시키는 에너지믹스를 제안한다. 본 논문은 또한 효율적인 에너지 정책을 담보하기 위해 CVM을 이용한 VSL 추정 연구를 지속적으로 축적할 필요가 있음을 강조한다.

설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2013)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제26권12호
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    • pp.605-619
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    • 2014
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

주파수조정용 에너지저장장치 운전제어 기술의 개발과 계통연계 자동제어 운전 (Development of Operation and Control Technology of Energy Storage System for Frequency Regulation and Operation by Grid Connected Automatic Control)

  • 임건표;최요한;임지훈
    • 전기학회논문지P
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    • 제65권4호
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    • pp.235-241
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    • 2016
  • Grid-connected, large-capacity energy storage systems (ESS) can be used for peak load supply, frequency regulation, and renewable energy output smoothing. In order to confirm the capability of battery ESS to provide such services, 4MW/ 8MWh battery ESS demonstration facility was built in the Jocheon substation on Jeju Island. The frequency regulation technology developed for the Jocheon demonstration facility then became the basis for the 28MW and 24MW frequency regulation ESS facilities installed in 2014 at the Seo-Anseong and Shin-Yongin substations, respectively. The operation control systems at these two facilities were continuously improved, and their successful commercialization led to the construction of additional ESS facilities all over Korea in 2015. In seven (7) locations nationwide (e.g., Shin-Gimje and Shin-Gyeryeong), a total of 184 MW of ESS had been commercialized in 2016. The trial run for the new ESS facilities had been completed between April and May in 2016. In this paper, results of the trial run from each of the ESS facilities are presented. The results obtained from the Seo-Anseong and Shin-Yongin substations during a transient event by a nuclear power plant trip are also presented in this paper. The results show that the frequency regulation battery ESS facilities were able to quickly respond to the transient event and trial run of ESS is necessary before it is commercialized.

경제성분석 프로그램을 이용한 도심형 마이크로그리드 최적 설계 (Optimal Design of Urban MICROGRID using Economical Analysis Program)

  • 유승덕;임성우;임유석;황성욱;이학주
    • KEPCO Journal on Electric Power and Energy
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    • 제8권2호
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    • pp.69-72
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    • 2022
  • This paper actually investigates the load on major large-scale buildings in the downtown area, examines the economic feasibility of installing PV and ESS in a microgrid target building, and evaluates whether an electric vehicle capable of V2G through two buildings is effective as an economical analysis program (HOMER) was analyzed using. It is economical to install a mixture of ESS rather than using the whole PV, and it is shown that if there is an electric vehicle using the V2G function of EV, there is an economic effect to replace the PV. So that Incentives and policies are needed to replace a large area of PV and utilize the existing parking lot to lead EV as a resource of the microgrid. Currently, P2X technology that stores power as ESS or converts it to other energy to control when surplus renewable energy occurs in large-capacity solar power plants and wind farms, etc. This is being applied, and efforts are being made to maintain the stability of the system through the management of surplus power, such as replacing thermal energy through a heat pump. Due to the increase in electric vehicles, which were recognized only as a means of transportation, technologies for using electric vehicles are developing. Accordingly, existing gas stations do not only supply traditional chemical fuels, but electricity, and super stations that also produce electricity have appeared. Super Station is a new concept power plant that can produce and store electricity using solar power, ESS, V2G, and P2G. To take advantage of this, research on an urban microgrid that forms an independent system by tying a large building and several buildings together and supplies power through a super station around the microgrid is in full swing.

Application of SFCL on Bus Tie for Parallel Operation of Power Main Transformers in a Fuel Cell Power Systems

  • Chai, Hui-Seok;Kang, Byoung-Wook;Kim, Jin-Seok;Kim, Jae-Chul
    • Journal of Electrical Engineering and Technology
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    • 제10권6호
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    • pp.2256-2261
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    • 2015
  • In the power plant using high temperature fuel cells such as Molten Carbonate Fuel Cell(MCFC), and Solid Oxide Fuel Cell(SOFC), the generated electric power per area of power generation facilities is much higher than any other renewable energy sources. - High temperature fuel cell systems are capable of operating at MW rated power output. - It also has a feature that is short for length of the line for connecting the interior of the generation facilities. In normal condition, these points are advantages for voltage drops or power losses. However, in abnormal condition such as fault occurrence in electrical system, the fault currents are increased, because of the small impedance of the short length of power cable. Commonly, to minimize the thermal-mechanical stresses on the stack and increase the systems reliability, we divided the power plant configuration to several banks for parallel operation. However, when a fault occurs in the parallel operation system of power main transformer, the fault currents might exceed the interruption capacity of protective devices. In fact, although the internal voltage level of the fuel cell power plant is the voltage level of distribution systems, we should install the circuit breakers for transmission systems due to fault current. To resolve these problems, the SFCL has been studied as one of the noticeable devices. Therefore, we analyzed the effect of application of the SFCL on bus tie in a fuel cell power plants system using PSCAD/EMTDC.

75kW 용융탄산염 연료전지 시스템의 MBOP 개발 (The Ejector Design and Test for 5kW Molten Carbonate Fuel Cell)

  • 김범주;김도형;이정현;강승원;임희천
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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    • pp.353-356
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    • 2009
  • A pivotal mechanical balance of plant for 75kW class molten carbonate fuel cells comprise of a catalytic burner and an ejector which has been designed and tested in KEPRI(Korea Electric Power Research Institute). The catalytic burner, which oxidizes residual fuel in the anode tail gas, was operated at several conditions. Some problems arose due to local overheating or auto-ignition, which could limit the catalyst life. The catalytic burner was designed by considering both gas mixing and gas velocity. Test results showed that the temperature distribution is very uniform. In addition, an ejector is a fluid machinery to be utilized for mixing fluids, maintaining vacuum, and transporting them. The ejector is placed at mixing point between the anode off gas and the cathode off gas or the fresh air Several ejectors were designed and tested to form a suction on the fuel tail gas and balance the differential pressures between anode and cathode over a range of operating conditions. The tests showed that the design of the nozzle and throat played an important role in balancing the anode tail and cathode inlet gas pressures. The 75kW MCFC system built in our ejector and catalytic burner was successfully operated from Novembe, 2008 to April, 2009. It recorded the voltage of 104V at the current of 754A and reached the maximum generating power of 78.5kW DC. The results for both stand-alone and integration into another balance of plant are discussed.

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이중여자 유도형 풍력발전기 기반 풍력단지의 계통 연계점 전압제어 (Voltage Control for a Wind Power Plant Based on the Available Reactive Current of a DFIG and Its Impacts on the Point of Interconnection)

  • ;김진호;;강용철
    • 전기학회논문지
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    • 제65권1호
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    • pp.23-30
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    • 2016
  • Wake effects cause wind turbine generators (WTGs) within a wind power plant (WPP) to produce different levels of active power and subsequent reactive power capabilities. Further, the impedance between a WTG and the point of interconnection (POI)-which depends on the distance between them-impacts the WPP's reactive power injection capability at the POI. This paper proposes a voltage control scheme for a WPP based on the available reactive current of the doubly-fed induction generators (DFIGs) and its impacts on the POI to improve the reactive power injection capability of the WPP. In this paper, a design strategy for modifying the gain of DFIG controller is suggested and the comprehensive properties of these control gains are investigated. In the proposed scheme, the WPP controller, which operates in a voltage control mode, sends the command signal to the DFIGs based on the voltage difference at the POI. The DFIG controllers, which operate in a voltage control mode, employ a proportional controller with a limiter. The gain of the proportional controller is adjusted depending on the available reactive current of the DFIG and the series impedance between the DFIG and the POI. The performance of the proposed scheme is validated for various disturbances such as a reactive load connection and grid fault using an EMTP-RV simulator. Simulation results demonstrate that the proposed scheme promptly recovers the POI voltage by injecting more reactive power after a disturbance than the conventional scheme.

UAV 공간정보 기반의 태양광발전소 부지의 일사량 분석 (The analysis of solar radiation to solar plant area based on UAV geospatial information system)

  • 이근상;이종조
    • 지적과 국토정보
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    • 제48권1호
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    • pp.5-14
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    • 2018
  • 최근 신재생에너지 정책의 영향으로 태양광발전소 건설이 꾸준히 증가하고 있다. 고효율 태양광발전소 사업을 위해서는 태양광발전소 부지에 대한 일사량 분석자료를 이용하여 태양광 패널에 대한 최적의 위치와 방향을 결정하는 것이 매우 중요하다. 본 연구에서는 UAV 공간정보를 기반으로 취득한 DEM 자료를 이용하여 태양광발전소 부지에 대한 일사량 분석을 실시하였다. 분석 결과 2017년 평균 일사량은 $1,474,466W/m^2$ 로 계산되었으며 대상면적을 고려한 전체 일사량은 $33,639MW/m^2$를 보였다. 월별 일사량을 분석하는 것은 태양광발전소 유지보수 업무 측면에서 중요하다. 월별 태양광발전소 부지의 평균일사량 분석에서는 5~7월의 평균 일사량이 $160,000W/m^2$ 이상으로 계산되었으며 1~2월 및 11~12월의 평균 일사량은 $80,000W/m^2$ 이하로 나타났다. 또한 본 연구에서는 UAV 공간정보로부터 계산된 일사량과 국립기상과학원에서 제시한 결과와 비교하였으며, 대상지역의 93.7%가 남향으로 구성되어 있기 때문에 대상지의 평균 일사량이 국립기상과학원의 전국 자료에 비해 약간 높게 나타났다. 따라서 본 연구는 UAV를 이용하여 새로 개발된 태양광발전소 부지에 대한 일사량을 신속하게 계산하는데 이용될 수 있으리라 판단된다.

MW급 EGS 지열발전 상용화 기술개발사업의 추진 배경 및 계획 (Research Background and Plan of Enhanced Geothermal System Project for MW Power Generation in Korea)

  • 윤운상;송윤호;이태종;김광염;민기복;조용희;전종욱
    • 터널과지하공간
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    • 제21권1호
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    • pp.11-19
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    • 2011
  • 지열에너지는 여러 신재생에너지원 중에서도 기저부하를 담당할 수 있는 중요한 자원으로 인식되고 있다. 국내에서도 천부지열을 이용한 지열냉난방은 효율 높은 신재생에너지 활용 사업으로 그 보급이 활성화 되어 있다. 반면, 전세계적으로 지열 발전 기술이 진일보하고, 그 시장이 크게 확대되고 있는 상황에서 아직까지 국내의 심부 지열을 이용한 지열 발전 기술은 낮은 단계에 머무르고 있다. 이러한 조건에서 2010년 12월에 국내 최초의 EGS(Enhanced Geothermal System) 지열 발전 상용화 기술 개발 과제가 착수되었다. 총 5개년의 기간으로 수행되는 이 과제는 2단계로 구분되어 진행될 계획이다. 처음 2년의 1단계에서는 3 km 심도에서 최소 $100^{\circ}C$의 지열저류층 온도를 확인하는 것을 주요 과제 내용으로 하여 지중 지열수 순환시스템의 설계가 이루어질 예정이다. 이후 3년을 통해 수행될 2단계에서는 5 km 심도의 생산정과 주입정 등 두 개의 지열발전정을 설치하고, 수리자극을 통하여 온도 $180^{\circ}C$의 지열저류층에서 유량 40 kg/s 이상의 지열수를 활용하는 MW급 지열발전소를 건립 운영하게 된다. 이 사업을 성공적으로 추진하기 위하여 현재 지질, 수리지질, 지구물리, 암석역학, 플랜트 엔지니어링 등 다양한 분야의 산학연 연구 기관 등이 망라되어 연구진을 구성한 상태이며, 이후 관심있는 여러 기관과 연구자들의 지원과 참여를 기대하고 있다.