Exergy analysis of a co-generation plant

Abstract

Limitations of traditional first-law analysis, based upon thermodynamic performance of process unit coupled with mass and energy balances, are not a serious limitation when dealing with familiar systems. However, when dealing with more uncongenial, complex ones, it provides incomplete insight for such evaluation. These limitations came from the fact that first-law analysis does not indicate the sources or magnitudes of entropy production, which is, by the second law, essential criterion for scaling losses. An evaluation of plant performance will usually require a comparison of the thermodynamic performance of process units with available data from existing plants. Therefore, exergy analysis is more than useful, providing information about magnitudes of losses and their distribution throughout the system as well. Such analysis is very thankful at the level of process units but applied on higher system levels e.g. the comparison of overall plant performance (total system) or the performance of subsystems, represents the valuable method for indicating where research resources can be directed to best advantage.

Tactical techno-economic analysis of electricity generation from forest, fossil, and wood waste fuels in a heating plant

“…Changes in the peat and forest fuel procurement volumes A1, A2, and A3, supply chains that include an energy efficiency of 19% and forest technology rates of 100, 300, and 1000%, respectively; B1, B2, and B3, supply chains that include an energy efficiency of 42% and forest technology rates of 100, 300, and 1000%, respectively process has a direct influence on fuel consumption. Same results have also reported abroad [6]. Increasing the forest technology rate clearly affected the levels of the peat and forest fuels.…”

“…3, In this paper, we have defined combined heat and power (CHP) to mean heat produced by combustion of fuel to drive a steam-based generator, and power in the form of electrical energy; both forms of energy can be used by the plant that produces them, or sold to other customers, including other units of the same company. This is also referred to as cogeneration [6]. According to a recent survey, managers of Finish energy plants will aim to increase energy production from renewable fuels at the expense of fossil fuels [7].…”

Estimating the value of energy saving in industry by different cost allocation methods

“…environmental impacts 15. The exergy method is based on the general principles of exergy analysis presented in the literature 14–18 and widely applied to thermodynamic evaluation of thermal power plants 19–21.…”

Exergy efficiency analysis of lignite-fired steam generator

“…The proposed combined cycle plant uses water as a working fluid in the topping cycle and an ammonia-water mixture in the bottoming cycle and, according to the study, it is 4% more efficient than the standalone Rankine cycle operating on a condensing mode. The work [24] presents a simplified method for determination of exergy efficiency of a steam-turbine cogeneration installation, taking into account the efficiency of separate plant components. A case study of detailed exergy analysis conducted in a coal-fired power plant unit is presented in [25].…”