The paper addresses the problem of the existence and quantification of the exergy of non-equilibrium systems. Assuming that both energy and exergy are a priori concepts, the Gibbs “available energy” A is calculated for arbitrary temperature or concentration distributions across the body, with an accuracy that depends only on the information one has of the initial distribution. It is shown that ...

The benefits are demonstrated of using exergy to understand the efficiencies of electrical power technologies and to assist improvements. Although exergy applications in power systems and electrical technology are uncommon, exergy nevertheless identifies clearly potential reductions in thermodynamic losses and efficiency improvements. Various devices are considered, ranging from simple electric...

Availability analysis is an effective approach to studying energy conversion in systems and identifying inefficiency. In the present study, a single-zone model was used to examine energy performance parameters and heat release rates. The governing equation of availability analysis was applied in the model, and the possibility of using biodiesel produced from sunflower oil as diesel engine was i...

Given the likelihood that carbon-based fuels will continue to play a major role in electricity generation, carbon capture and storage systems will be a necessary part of future generating capacity. With this research project, we aim to develop a framework for quantitative evaluation of existing and proposed carbon-capture technologies. This framework is based on an exergy-based systems analysis...

In classical thermodynamic, maximum power obtained from system (or minimum power supplied to system) defined as availability (exergy), but availability term is only used for reversible systems. In reality, there is no reversible system, all systems are irreversible, because reversible cycles doesn’t include constrains like time or size and they operates in quasi-equilibrium state. Purpose of th...

The Energetic and Exergetic performances evaluating models were built for a agricultural greenhouse cooling with groundwater-style GSHP system (GSHPs) in Northern China. The Exergy destruction (Exdest), Exergy efficiency(ε) and coefficient of performance (COP) were estimated and presented based on summer cooling test monitored data and the simulation models. Analyzed results indicate that the e...

In this study, the overall performance of air PV/T, based on energy and exergy analysis has been investigated. Two combinations of air PV/T, which consist of unglazed and glazed air PV/T, are considered. Thermal analysis and numerical calculations were carried out, and the performance parameters of the system for the climate conditions of Kerman were studied. The results are presented in graphs...

Nearly all energy conversion systems, and especially electricity generation plants do not operate at nominal conditions throughout their useful life: periodic or semi-periodic changes in the availability of the resource affect solar (thermal and PV), wind, hydraulic and geothermal plants, which in reality operate at off-design conditions for most of their life. To a smaller scale, fossil-fuelle...