Results 141 to 150 of about 4,154 (188)

On Intrinsic Exergy Efficiency and Heat Pumps

Chemical Engineering Research and Design, 2000
Exergy analysis provides an assessment of the degree of thermodynamic perfection of a process. Several exergy efficiency definitions have been proposed among which is the intrinsic efficiency which is based on the concept of transiting exergy. This method of analysis has been applied to absorption heat pumps and the results are presented.
Jalel Labidi
exaly   +2 more sources

Primary exergy efficiency—Effect of system efficiency environment to benefits of exergy savings

Energy and Buildings, 2016
Abstract Improving energetic performance is a key factor in making societies more sustainable. One way to analyze energetic performance is to use methods based on the second law of thermodynamics. Exergy analysis is such a method. With exergy analysis thermodynamic losses of the studied system can be found.
Kohl, Thomas, Järvinen, Mika, Ahtila, Pekka, Laukkanen, Timo   +4 more
openaire   +5 more sources

Efficiencies of exergy transductions

Applied Energy, 1980
Abstract Exergy is conserved in thermodynamically reversible heat engines and heat pumps. Using a reversible heat engine to stimulate a reversible heat pump, available power and exergy may be exchanged, the total amount of exergy being conserved. For such a combined system, either more heat may be released at a lower temperature or energy may be ...
Mohey Hussein, R.J. Wood, P.W. O'Callaghan, S.D. Probert   +3 more
openaire   +1 more source

Exergy efficiency and conversion of chemical reactions

Energy Conversion and Management, 1998
An exergy analysis of the ammonia oxidation in nitrous oxide has been performed using alternatively the conventional second law efficiency and the more recently proposed intrinsic exergy efficiency. It is shown that the second law efficiency does not account for the conversion effect on the overall performance of a chemical system while the intrinsic ...
M. Sorin, J.-C. Bonhivers, J. Paris
openaire   +2 more sources

Energy and Exergy Efficiencies

2012
Energy and exergy efficiencies are considered to be useful for the assessment of energy conversion systems and for improved performance. By considering both of these efficiencies, the quality and quantity of the energy used to achieve a given objective is properly accounted for, and the degree to which efficient and effective use of energy resources is
Mehmet Kanoğlu, Yunus A. Çengel, İbrahim Dinçer   +2 more
openaire   +1 more source

Energy and exergy efficiencies for society

Journal of the Energy Institute, 2008
AbstractExergy is defined as the maximum amount of work and exergy concept gives an effective way by using the conservation of energy principle. This concept is used to evaluate energy use of societies. In this respect, energy and exergy efficiencies are defined to evaluate sector efficiencies in societies.
Ü. Çamdali, M. Tunç
openaire   +1 more source

Efficiency and Exergy Efficiency of a Heat Engine with the Maximum Power

Russian Journal of Physical Chemistry A, 2020
The exergy efficiency was evaluated based on the Alikhanov–Novikov maximum power principle. An expression for the efficiency of a heat engine related to the mechanism of heat transfer from the heat source to the generator was obtained. The exergy losses were compared for several industrial thermal power plants described in the literature.
L. I. Kheifets, V. L. Zelenko
openaire   +1 more source

Comparing hydraulic and polytropic efficiencies with exergy efficiency

Exergy, An International Journal, 2001
Abstract This paper uses the hydraulic and polytropic efficiency concepts in a domain wider than that of their original definition. A generalized Bernoulli equation taken from previous papers is also considered. The aim is to find a general statement yielding hydraulic efficiency values ranging from one to zero, and a relative dissipative term ...
Giacomo Bisio, Giuseppe Rubatto
openaire   +1 more source

Exergy efficiency of a solar photovoltaic array based on exergy destructions

Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 2010
In this article, an attempt has been made to investigate the exergetic performance of a solar photovoltaic (PV) array. A detailed energy and exergy analysis has been carried out to calculate the operating and electrical parameters, exergy destruction components, and exergy efficiency of a typical PV array.
F Sarhaddi, S Farahat, H Ajam, A Behzadmehr   +3 more
openaire   +1 more source

Energy efficiency, no: It's exergy efficiency!

International Journal of Hydrogen Energy, 2007
Elevated energy efficiencies seem politically beyond dispute as measures against anthropogenic climate change. Energy efficiencies, however elevated they become, remain within the applied energy system, though. The paper draws attention to the exergo-thermodynamical system change of splitting up energy into exergy and anergy where exergy is the maximum
openaire   +1 more source