• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.76-83
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• 2003

Exergetic and thermoeconomic analyses were performed fer a 137-MW steam power plant. In these analyses, mass and energy conservation laws were applied to each component of the system. Quantitative balance of the exergy and exergetic cost for each component, and for the whole system was carefully considered. The exergo-economic model, which represented the productive structure of the system was used to visualize the cost formation process and the productive interaction between components. The computer program developed in this study can determine production costs of power plants, such as gas-and steam-turbines plants and gas-turbine cogeneration plants. The program can also be used to study plant characteristics, namely, thermodynamic performance and sensitivity to changes in process and/or component design variables.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.689-696
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• 2001

Exergetic and thermoeconomic analysis were performed for a 200kW Phosphoric Acid Fuel Cell(PAFC) plant which offers many advantage for cogeneration in the aspect of high electrical efficiency and low emission. This analytical study was based on the data obtained by in-field measurement of PC25 fuel cell plant to find whether this system is viable economically. For 100% load condition, the electrical efficiency and the unit cost of electricity are about 45% and 0.032 $/kWh respectively, which turn out to be much better than those for the 1000kW gas turbine cogeneration plant. Further, at lower loads, the unit costs of electricity and hot water increase slightly and consequently more economic operation is possible at any loads.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.222-227
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• 2000

At representative thermoeconomic theory to determine the unit cost of multiple products, there are the $\ulcorner$SPECO$\lrcorner$ method of Tsatsaronis's study group and the $\ulcorner$MOPSA$\lrcorner$ method of chung-ang university phase laboratory. Against this theory, we propose new theory called $\ulcorner$Thermoeconomics to divide the exergetic cost into each working fluid$\lrcorner$ in this study. Also, we apply new thermoeconomic theory to CGAM problem (30MW-grade imaginary gas turbine cogeneration power plant) that it is representative power system in thermoeconomics theory, and we fixed to interpreted the unit cost of electricity on the part of gas turbine and the unit cost of steam exergy(enthalpy) on the part of HRSG.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.962-969
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• 2000

Quality that character of energy is the same at every state in case of equal working fluid and net concept of material flow was applied to thermoeconomics about energy system, and we could naturally explain the suitable degree about this concept, also thermoecomic equations about general power plant was easily deduced. And deduced equations exactly corresponded with principle of thermoeconomics that overall input cost flow rate equal overall output cost flow rate. This equations is applied to gas turbine cogeneration power plant as one example and found the product unit cost. Also this product cost comparison could been naturally explained.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.360-371
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• 2003

The calculation of each unit cost of productions is very important for evaluating the economical efficiency and deciding the reasonable sale price. In the present, two methods of exergy costing on multiple energy systems are suggested to reduce the complexities of conventional SPECO method and MOPSA method and to improve the calculation efficiency of exergoeconomics. The suggested methods were applied to a gas-turbine cogeneration and the unit costs of the power and the steam energy were calculated as an example. The main points of our methods are the following three. First, one exergetic cost is applied to one cycle or system. Second, the suggested equations are the internal cost balance equation and the production cost balance equation. Third, necessary states in a system are only inlet and exit states of 1ha components producing energy.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1197-1202
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• 2009

Cost allocation on cogeneration is a methodology dividing the input of common cost to electricity cost and heat cost. In the cost allocation methodology of the electricity and heat on a cogeneration, there are energy method, work method, proportional method, benefit distribution method, reversible work method, various exergetic methods, and so on. In previous study, various cost allocation methodologies have been applied and analyzed on a gas-turbine cogeneration producing the 33.1 MW of electricity and the 32.2 Gcal/h of heat, a steam-turbine cogeneration producing the 22.2 MW of electricity and the 44.3 Gcal/h of heat, and combined-cycle cogeneration producing the 314.1 MW of electricity and the 279.4 Gcal/h of heat. In this study, we integrately analyze the results of previous studies and examine the generality and rationality each methodology. Additionally, a new point of view on the values of alternative electricity efficiency and alternative heat efficiency in the previous methodologies was proposed. As the integrated result, we conclude that reversible work method of various common cost allocation methodologies is most rational.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.9
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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.

• Proceedings of the SAREK Conference
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• 2008.11a
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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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.4
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• pp.252-259
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• 2009

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 steam, and then we allocated 3,150 $/h of fuel cost to electricity cost and steam cost. Also, we compared with various cost allocation methods. As the result, we conclude that reversible work of various kinds of worth basis evaluates the worth of heat and electricity most reasonably.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.871-878
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• 2000

Exergetic and thermoeconomic analysis were performed for a 500-MW combined cycle plant and a 137-MW steam power plant without decomposition of exergy stream of matter into thermal and mechanical exergies. The calculated costs of electricity are almost same within 0.5% as those obtained by the thermoeconomic method with decomposition of exergy into thermal and mechanical exergies of the combined cycle plant. However for the gas-turbine cogeneration plant having different kinds of products. the difference in the unit costs of products, obtained from the two methodologies is about 2%. Such outcome indicates that the level at which the cost balances are formulated does not affect the result of thermoeconomic analysis, that is somewhat contradictory to that concluded previously.