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1
Content available Thermodynamic analysis of a combined cycle power plant located in Jordan: A case study
Bataineh Khaled, Khaleel Bara A.
Archives of Thermodynamics
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2020
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Vol. 41, no 1
95--123
EN
Efficiency and electrical power output of combined cycle power plants vary according to the ambient conditions. The amount of these variations greatly affects electricity production, fuel consumption, and plant incomes. Obviously, many world countries have a wide range of climatic conditions, which impact the performance of power plants. In this paper, a thermodynamic analysis of an operating power plant located in Jordan is performed with actual operating data acquired from the power plant control unit. The analysis is performed by using first and second laws of thermodynamics. Energy and exergy efficiencies of each component of the power plant system are calculated and the effect of ambient temperature on the components performance is studied. The effects of gas turbine pressure ratio, gas turbine inlet temperature, load and ambient conditions on the combined cycle efficiency, power outputs and exergy destruction are investigated. Energy and exergy efficiencies of the combined cycle power plant are found as 45.29%, and 42.73% respectively when the ambient temperature is 34°C. Furthermore, it is found that the combustion chamber has the largest exergy destruction rate among the system components. The results showed that 73% of the total exergy destruction occurs in the combustion chamber when the ambient temperature is 34°C. Moreover, the results show that the second major exergy loss is in HRSC. The results show that the energy and exergy efficiency of the combined cycle power plant decreases as the ambient temperature increases. According to the calculation results, improvement and modification suggestions are presented.
2
Wpływ właściwości czynników chłodniczych na straty egzergii w pompie ciepła
Muszyński T., Andrzejczyk R., Jakubowska B.
Ciepłownictwo, Ogrzewnictwo, Wentylacja
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2016
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T. 47, nr 5
195--200
PL
Artykuł poświęcony jest wpływowi występujących w pompie ciepła strat egzergii na jej efektywność energetyczną, a co za tym idzie koszty funkcjonowania instalacji. Autorzy prezentują tu metodologię obliczeniową, która może być zastosowana w procesach projektowania układów cieplno-przepływowych. Obliczenia zostały wykonane na podstawie typowego układu powietrznej pompy ciepła pracujące w klimacie środkowo-europejskim. Ponadto w artykule wykonano analizę techniczno-ekonomiczną pompy ciepła z wykorzystaniem wybranych czynników roboczych, które mogą być stosowane w przyszłości.
EN
The article prestents the influence of exegetical losses in the heat pump on its energy efficiency and the cost of the installation. The authors shows a calculation methodology which-could be applied in the design of thermal fluid systems. The calculations were made based on the typical air source heat pump working in a Middle Europe climate. The whole was supplemented with technical and economic analysis carried out on the of a selected group of perspective operating fluids applicable to heat pumps.
3
Content available Straty egzergii w okrętowym kotle opalanym
Matuszak Z., Jaśkiewicz M.
Autobusy : technika, eksploatacja, systemy transportowe
|
2016
|
R. 17, nr 11
98--102
PL
Na przykładzie okrętowego kotła opalanego (jednego z jego typów, instalowanych na statkach transportowych) scharakteryzowano rodzaje strat egzergii w poszczególnych elementach składowych kotła, jak i w procesie wytwarzania czynnika - pary technologicznej. Podstawą analizy jest struktura funkcjonalna kotła opalanego odpowiadająca jego pracy na jednostce pływającej. Analizę poprzedza zdefiniowanie podstawowych pojęć związanych z użytymi do analizy określeniami i wielkościami nt. strat egzergii i sprawności kotła. W końcowej części przedstawiono trudności z oszacowaniem wielkości strat ezgergii i sprawności egzergetycznej okrętowego kotła opalanego w rzeczywistych warunkach eksploatacyjnych.
EN
The analysis is based on the functional structure of the boiler corresponding to its operation in a vessel. A marine oil-fired boiler (one of the types installed in merchant vessels) is discussed in terms of kinds of exergy losses in particular components of the boiler and in the process of producing the eergy carrier - process steam. The analysis is preceded by the definitions of basic concepts connected with the terms and quantities referring to exergy loss and boiler efficiency. The final part indicates difficulties with the estimation of the amount of exergy losses and oil-fired boiler efficiency in actual operating conditions.
4
Content available Thermodynamical motivation of the Polish energy policy
Ziębik A.
Archives of Thermodynamics
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2012
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Vol. 33, no. 4
3-21
EN
Basing on the first and second law of thermodynamics the fundamental trends in the Polish energy policy are analysed, including the aspects of environmental protection. The thermodynamical improvement of real processes (reduction of exergy losses) is the main way leading to an improvement of the effectivity of energy consumption. If the exergy loss is economically not justified, we have to do with an error from the viewpoint of the second law analysis. The paper contains a thermodynamical analysis of the ratio of final and primary energy, as well as the analysis of the thermo-ecological cost and index of sustainable development concerning primary energy. Analyses of thermo-ecological costs concerning electricity and centralized heat production have been also carried out. The effect of increasing the share of high-efficiency cogeneration has been analyzed, too. Attention has been paid to an improved efficiency of the transmission and distribution of electricity, which is of special importance from the viewpoint of the second law analysis. The improvement of the energy effectivity in industry was analyzed on the example of physical recuperation, being of special importance from the point of view of exergy analysis.
5
Energia czy egzergia
Szargut J.
Rynek Energii
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2010
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nr 5
3-5
PL
W języku potocznym słowem "energia" określa się zwykle tylko energię podwyższonej jakości. Jakość tę określa egzergia, nie podlegająca prawu zachowania. Straty egzergii są proporcjonalne do entropii generowanej. Należy dążyć do ich zmniejszania w granicach opłacalności ekonomicznej i możliwości technologicznych. Znajomość analizy egzergetycznej jest niezbędna przy projektowaniu i udoskonalaniu procesów energetycznych.
EN
In a colloquial speech the word "energy" is used for the kinds of energy characterized with a higher quality. In a scientitic speech the quality of energy is expressed by means of exergy, exempt from the law of conservation. The losses of exergy are proportional to the generated entropy. For the reduction of these losses it should be striven in the limits of economic profitability and technological possibilities. The knowledge of the exergy analysis is indispensable in the design and improvement of energy processes.
6
Content available Application of exergy analysis for evaluation of CO2 emission from operation of steam power unit
Stanek W., Budnik M.
Archives of Thermodynamics
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2010
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Vol. 31, no. 4
81-91
EN
Szargut proposed the algorithm for determination of the influence of irreversibility of components of thermal process on the emission of CO2 [6]. In the presented paper, basing on Szargut's proposal, the example of analysis of influence of operational parameters of coal fired power plant on the local increase of CO2 emission is presented. The influence of operational parameters on the local exergy losses appearing in components of investigated power plant are simulating making use of the semi-empirical model of power plant.
7
Content available remote Losses of exergy in a marine oil-fired boiler
Matuszak Z.
Archives of Thermodynamics
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2008
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Vol. 29, no. 4
97-108
EN
A marine oil-fired boiler (one the types installed on merchant vessels) is discussed in terms of kinds of exergy losses in particular component of the boiler and in the process of producing the energy carrier - process steam. The analysis is based on the functional structure of the boiler corresponding to its operation in a vessel. The analysis is preceded by the definitions of basic concepts connected with the terms and quantities referring to exergy loss and boiler efficiency. The final part of the paper indicates difficulties with the estimation of the amount of exergy losses and oil-fired boiler efficiency in actual operating conditions.
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