• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.579-582
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• 2008

PEM Fuel cell system was designed and constructed to use as a power source of unmanned aerial vehicles(UAV) in the present study. Sodium borohydride was selected as a hydrogen source and was decomposed by catalytic hydrolysis reaction. Fuel cell system consists of a fuel cell stack, a hydrogen generation system(HGS), and power management system(PMS). HGS was composed of a catalytic reactor, micropump, fuel cartridge, and separator. Hybrid power system between lithium-polymer battery and fuel cell was developed. The fuel cell system was integrated and packaged into a blended wing-body UAV. Energy density of the total system was 1,000 $W{\cdot}hr/kg$ and high endurance more than 5 hours was accomplished in the ground tests.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.85-92
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• 2016

Since the power density of the VHTR(Very High Temperature Reactor) is lower, there is less possibility of core melt. VHTR has no risk of explosion caused by hydrogen generation when the loss of coolant accident occurs, which is another advantage. Along with safety benefit, it can be used as a process heat supplier near demand facilities because coolant temperature is very high enough to be used for industrial purpose. In this paper, we designed the primary system using VHTR and the secondary system providing electricity and process heat. Based on that 350 MW thermal reactor proposed by NGNP(Next Generation Nuclear Part), we developed conceptual model that the IHX(Intermediate Heat Exchanger) loop transports 300 MW thermal energy to the secondary system. In addition, we analyzed thermodynamic behavior and performed the efficiency analysis and optimization study depending on major parameters.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.4
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• pp.399-404
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• 2005

In this paper, a hybrid photovoltaic fuel-cell generation system employing an electrolyzer for hydrogen generation and battery for storage purpose is designed and simulated. The system is applicable for remote areas or isolated DC loads. Control strategy has been considered to achieve permanent power supply to the load via the photovoltaic/battery or the fuel cell based on the power available from the sun. MATLAB and SIMULINK have been used for the simulation work. A sensitivity analysis is conducted for various load level based on availability of solar radiation.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.4
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• pp.358-368
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• 2023

The fuel cell market is expected to grow rapidly. Therefore, it is necessary to scale up fuel cells for buildings, power generation, and ships. A multi-stack system can be an effective way to expand the capacity of a fuel cell. Multi-stack fuel cell systems are better than single-stack systems in terms of efficiency, reliability, durability and maintenance. In this research, we developed a residential fuel cell stack and system model that generates electricity using the fuel cell-photovoltaic hybrid system. The efficiency and hydrogen consumption of the fuel cell system were calculated according to the three proposed power distribution methods (equivalent, Daisy-chain, and optimal method). As a result, the optimal power distribution method increases the efficiency of the fuel cell system and reduces hydrogen consumption. The more frequently the multi-stack fuel cell system is exposed to lower power levels, the greater the effectiveness of the optimal power distribution method.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.524-527
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• 2000

An electroenzymatic system to oxidize veratryl alcohol of on electrodes with in-situ generated hydrogen peroxide was studied. We investigated hydrogen peroxide generation, current efficiency, and veratryl alcohol oxidation in the electrode system at various conditions. The reaction rates of veratryl alcohol oxidation were compared in an electrochemical, an electroenzymatic, and an usual biochemical systems to prove the concept of electroenzymatic oxidation.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1167-1168
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• 2006

Recently, the concern for environmental issue has been rising in the world such as global warming and breaking of ozone barrier by exhausting carbon dioxide(CO2) and Freon. In this situation, Photovoltaic(PV) and hydrogen energy system for utilizing clean and renewable energy was highlighted to contribute very much against the global warming prevention. Until now, authors have studied EMTDC model Development of Solar-powered Hydrogen production system and manufactured the 600W class actual PV-SPE system. Which was established in 2004 to produce highly pure hydrogen energized by PV power generation system. Sooner, authors will establish 100kW class PV-SPE system. Economically, this system produce large amount of hydrogen. In this paper, all data of 100kW class PV-SPE system will be simulated by using PSCAD/EMTDC.

• Journal of the Korea Computer Graphics Society
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• v.15 no.2
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• pp.35-40
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• 2009

In this paper, we present the web3D-based virtual reality(VR) system for the safety education of the hydrogen station. Currently, hydrogen is considered the next generation energy, and hydrogen station is a part of core infrastructure in hydrogen industry. However, the experience of safety equipment in the hydrogen station is limited to the non-experts, because it is a restricted area in general industry. Therefore, using the event driven method, we develop the VR system to transfer the information of hydrogen station to the non-experts. Using our system, user experiences the safety concerns in the hydrogen station, and also learn the informations of hydrogen energy.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.55-58
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• 2007

To check the feasibility of SMART (Steam Methane Advanced Reforming Technology)system, an experimental investigation was conducted. A fluidized bed reactor of diameter 0.052 m was operated cyclically up to the $10^{th}$ cycle, alternating between reforming and regeneration conditions. FCR-4 catalyst was used as the reforming catalyst and calcined limestone (domestic, from Danyang) was used as the $CO_2$ absorbent. Hydrogen concentration of 98.2% on a dry basis was reached at $650^{\circ}C$ for the first cycle. This value is much higher than $H_2$ concentration of 73.6% in the reformer of conventional SMR (steam methane reforming) system. However, the hydrogen concentration decreased because the $CO_2$ capture capacity decreased as the number of cycles increased.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.235-240
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• 2008

The recent development of efficient thermal prime movers for distributed generation id changing the focus of the production of electricity from large centralized power plants to local generation units scattered over the territory. The scientific communality is addressing the analysis and planning of the distributed energy resources(der) with wide spread approaches, taking into account technical, environmental, economical and social issues. The coupling of cogeneration system to absorption/electric chillers or heat pumps as well as the interactions with renewable sources, allow for setting up multi-generation systems for building cooling heating and power(BCHP) systems of different energy vectors such as electricity, heat(at different enthalpy levels), cooling power, hydrogen, various chemical substances and so forth. Adoption of the composite multi-generation systems may lead to significant benefits in term of higher efficiency, reduced $CO_2$ emissions and enhanced economy. This paper outlines the main aspects of the BCHP system framework, illistrating its characteristics and summarizing the relevant distributed multi-generation structures.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.11
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• pp.57-68
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• 2013

The market for distributed power generation based on renewable energy is increasing, particularly for standalone mini-grid applications in developing countries with limited energy resources. Stand-alone power systems (SAPS) are of special interest combined with renewable energy design in areas not connected to the electric grid. Traditionally, such systems have been powered by diesel engine generator sets (DEGS), but also hybrid systems with photovoltaic and/or wind energy conversion systems (WECS) are becoming quite common nowadays. Hybrid energy systems can now be used to generate energy consumed in remote areas and stand-alone microgrids. This paper describes the design, simulation and feasibility study of a hybrid energy system for a stand-alone power system. A simulated model is developed to investigate the design and performance of stand-alone hydrogen renewable energy systems. The analysis presented here is based on transient system simulation program (TRNSYS) with realistic ventilation load of a large store. Design of a hybrid energy system is site specific and depends on the resources available and the load demand.