• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.345-350
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• 2008

The present study has been conducted to develop a heat recovery system for a 1 MW class gas engine based cogeneration system. In the cogeneration system, heat is recovered from two parts, which are jacket water and exhaust gas. The heat from the jacket water is recovered by a plate type heat exchanger and used for the room heating and/or hot water supply. The heat from the exhaust gas is used to generate steam. For both of the heat recovery devices, 1/5 scaled tests are performed and the data are compared to the conventional correlations for the design.

• 한국태양에너지학회 논문집
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• 제26권2호
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• pp.35-42
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• 2006

Solar Thermal-Electric Integrated system can be used to generate heat and electricity simultaneously and can improve indoor all qualify. So, it can save heating and electricity cost as it operates at relatively lower temperatures. In this study, one pv module was fixed on a normal wall and a pv module was mounted on a solarwall. And a ventilation fan in the solar energy cogeneration panel was operated from 12:00 to 17:00 hours. Experimental results are recorded and anaysized. The comparison of results show that the temperature of PV on solar energy cogeneration panel was decreased by $7{\sim}9^{\circ}C$ and the electrical output was improved by $2{\sim}3W$ compared with a PV system without solarwall.

• 설비공학논문집
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• 제20권9호
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• pp.624-630
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• 2008

When various kinds of outputs are produced from a single energy system, the methodology which allocates the common cost to each output cost is very important because it is directly related with the profit and loss of producers and purchasers. In the cost allocation methodology of the heat and the electricity on a cogeneration, there are energy method, work method, proportional method, benefit distribution method, exergetic methods, and so on. On the other hand, we have proposed a worth method which can be applied to any system. The definition of this methodology is that the unit cost of a product is proportion to the worth. Where, worth is a certain evaluating basis that can equalize the worth of products. In this study, we applied worth method to a steam-turbine cogeneration which produces 22.2 MW of electricity and 44.4 Gcal/h of heat, and then we allocated 2,578 $/h of common cost to electricity cost and heat cost. Also, we compared with various cost allocation methods. As the result, we conclude that exergy of various kinds of worth basis evaluates the worth of heat and electricity most reasonably on this system.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.351-356
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• 2008

When various kinds of outputs are produced from a single energy system, the methodology which allocates the common cost to each output cost is very important because it is directly related with the profit and loss of producers and purchasers. In the cost allocation methodology of the heat and the electricity on a cogeneration, there are energy method, work method, proportional method, benefit distribution method, various exergetic methods, and so on. On the other hand, we have proposed a worth evaluation method which can be applied to any system. The definition of this methodology is that the unit cost of a product is proportion to the worth. Where, worth is a certain evaluating basis that can equalize the worth of products. In this study, we applied this methodology to a gas-turbine cogeneration which produces 119.2 GJ/h of electricity and 134.7 GJ/h of heat, and then we allocated 3,150 $/h of fuel cost to electricity cost and heat cost. Also, we compared with various cost allocation methods. As the result, we conclude that exergy of various kinds of worth basis evaluates the worth of heat and electricity most reasonably on this system.

• 한국태양에너지학회 논문집
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• 제30권6호
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• pp.81-88
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• 2010

This study compared the feasibility of utilizing a wood bioenergy system over a conventional central heating and cooling system and a cogeneration system in an apartment complex. The performance of the three systems were compared in the following areas: energy consumption, environmental impact(output of CO2, CH4, and N2O), and life cycle cost. The results showed that energy performance of the wood bioenergy system was similar to the conventional central system (just a 1% improvement) but the cogeneration system showed a 12% reduction in energy consumption compared to the conventional system. In terms of environmental impact, the bioenergy system reduced pollutants by 50% while the cogeneration system reduced pollutants by 30% compared to the conventional system. Life cycle cost analysis indicated bioenergy and cogeneration to have an 8% and 19% improvement over the conventional system. The findings of the study suggest that it is both economically and environmentally beneficial to use a wood bioenergy system in place of a conventional central heating and cooling system in apartment complexes.

• 한국수소및신에너지학회논문집
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• 제29권5호
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• pp.490-496
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• 2018

Recently, the power and refrigeration cogeneration based on Kalina cycle has attracted much attention for more efficient utilization of low-grade energy. This study presents a thermodynamic performance analysis of a cogeneration cycle of power and absorption refrigeration based on Kalina cycle. The cycle combines Kalina cycle (KCS-11) and absorption cycles by adding a condenser and an evaporator between turbine and absorber. The effects of ammonia mass fraction and separation pressure were investigated on the system performance of the system. Results showed that the energy utilization of the system could be greatly improved compared to the basic Kalina cycle.

• 대한전기학회논문지:전력기술부문A
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• 제49권6호
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• pp.280-288
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• 2000

Recently, there has been growing interest in utilizing cogeneration(COGN) systems with a high-energy efficiency due to the increasing energy consumption and the lacking of energy resource. But an insertion of COGN system to existing power distribution system can cause several problems such as voltage variations, harmonics, protective coordination, increasing fault current etc, because of reverse power of COGN, especially in protective coordination. A study on a proper coordination with existing one is being required. The existing power distribution system is operated with radial type by one source and protection system is composed based on unidirectional power source. But an Insertion of COGN system to power distribution system change existing unidirectional power source system to bidirectional power source. Therefore, investigation to cover whole field of power distribution system must be accomplished such as changing of protection devices rating by increasing fault current, reevaluation of protective coordination. In this paper, simulation using PSCAD/EMTDC was accomplished to analyze effect of COGIN on distribution fault current. Also, the existing protection system of 22.9[kV] power distribution system and customers protection system to protect of COGIN was analyzed and the study on protective coordination between of two protection system accomplished.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.199-204
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• 2009

This study analyzed the central heating system and the cogeneration system among the methods of supplying energy which have application to the Hydrogen Fuel Cell system and apartment complexes for performance evaluations. Therefore, a feasibility study on the first application of this system in an apartment complexes was considered to evaluate the energy performance by the amount of fuel consumed by the system using Hydrogen Fuel Cell energy and environmental performance by the amount of greenhouse gas emissions. As a result, the Hydrogen Fuel Cell system consumes 83% of fuel while the cogeneration system consumes 81% of fuel comparison to conventional central heating system. The Hydrogen Fuel Cell and the cogeneration system produce 73%t and 70% of greenhouse gas emissions in comparison to conventional central heating system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1215-1217
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• 1999

Electrical studies are required to assure the proper integration of cogeneration facility into a industrial plant electrical system and the connected utility grid. Details of such study efforts are presented, including boundary limit for the system modeling, short-circuit and load flow studies, stability studies, load shedding studies, and harmonics studies.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.150-153
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• 1987

This paper describes the fundamentals, system configuration, existing situation and future prospect of the cogeneration system and valuation of its economic effects. Especially, increasing this system should be evaluated for national energy management deeply, because KEPCO has generation units eneugh which can be met demend currently and in the near future and nuclear power generation has been more than 50% of total generation.