scholarly journals SPLITTING THE TOTAL EXERGY DESTRUCTION INTO THE ENDOGENOUS AND EXOGENOUS PARTS OF THE THERMAL PROCESSES IN A REAL INDUSTRIAL PLANT

2016 ◽  
Vol 14 (2) ◽  
pp. 199 ◽  
Author(s):  
Goran Vučković ◽  
Mića Vukić ◽  
Mirko Stojiljković ◽  
Miloš Simonović
Keyword(s):  
Steam Generator ◽  
Energy System ◽  
The Other ◽  
Industrial Plant ◽  
Thermal Processes ◽  
Exergy Destruction ◽  
Dominant Effect ◽  
System Components

The total exergy destruction occurring in a component is not only due to the component itself (endogenous exergy destruction) but is also caused by the inefficiencies of the remaining system components (exogenous exergy destruction). Hence care must be taken in using the total exergy destruction of a component for making decisions to optimize the overall energy system. In this paper, a complex industrial plant is analyzed by splitting the component’s exergy destruction into its endogenous part (the part resulting totally from the component’s irreversibilities) and its exogenous part (resulting from the irreversibilities of the other components within the system). It is observed that the steam generator has the dominant effect. From the total exergy destruction in the steam generator, 1,097.63 kW or 96.95% come from internal irreversibilities in the component, while the influence of other components on the loss of useful work in the steam generator is only 3.05%.

scholarly journals Modelling of A Solar Thermal Energy System For Energy Efficiency Improvement In A Ceramic Plant

2021 ◽  
Vol 6 ◽  
pp. 31
Author(s):  
Miguel Castro Oliveira ◽  
Muriel Iten
Keyword(s):  
Energy Efficiency ◽  
Thermal Energy ◽  
Heat Recovery ◽  
Energy System ◽  
High Energy ◽  
Solar Thermal ◽  
Industrial Plant ◽  
Thermal Processes ◽  
Solar Thermal Energy ◽  
Ceramic Plant

The thermal energy use in the manufacturing plants is the most representative parcel of the total energy consumption within the European industry. Such is mainly attributed to the operation of high energy intensive thermal processes such as furnaces and boilers. The implementation of heat recovery technologies is a solution with a great potential to improve the operation of these processes and improve the overall energy efficiency in a plant. On the other hand, the use of renewable energy resources such as solar energy is highly relevant measure to decrease the use of fossil fuels, such as natural gas. This paper presents the modelling of a solar thermal energy system (STES) established by a water circuit and solar thermal collector for the heat supply to two boilers installed in a ceramic plant. Such system has been conceptualised in the scope of industrial practices, proposing solar heat for industrial processes (SHIP). The practical work in this paper aims to the development of a customised simulation tool for the modelling of heat recovery networks and thermal processes in manufacturing industry plants using the Modelica language. The system model has been developed using existing and newly developed equipment models. The simulation results were validated with measured data in the industrial plant, being consistent with the real values (e.g. highest deviation of about 0.01%). In addition to the boilers, the performed simulation allowed to achieve the sizing of the components of the water circuit, in particular for the pumping system (with a required supply of 0.747 kW of electric energy). A techno-economic assessment has been performed to evaluate the viability of the cproposed solution, showing a payback time of approximately 3 years, a total annual economic savings of about 25209 € and associated reduction of equivalent carbon dioxide emissions of about 170 ton/year.

Endogenous and Exogenous Exergy Destruction in Thermal Systems

2006 ◽  
Author(s):  
George Tsatsaronis ◽  
Solange O. Kelly ◽  
Tatiana V. Morosuk
Keyword(s):  
Exergy Analysis ◽  
System Optimization ◽  
Energy System ◽  
General Concept ◽  
System Component ◽  
Thermal System ◽  
Exergy Destruction ◽  
Thermal Systems ◽  
System Components ◽  
Refrigeration Machine

One of the roles of exergy analysis is to provide thermal system designers and operators with information useful for the system optimization. An exergy analysis identifies the sources of thermodynamic inefficiencies by evaluating the exergy destruction within each system component. However, care must be taken when using the total exergy destruction within a component to reach conclusions regarding the optimization of the overall energy system. The reason is that the total exergy destruction occurring in a component is not due exclusively to that component but is also caused by the inefficiencies within the remaining system components. The endogenous exergy destruction within a component is defined as that part of the component's exergy destruction that is independent of any change in the exergy destruction within the remaining components. The part of the component's exergy destruction which depends upon the changes of the exergy destruction within the other components is defined as the exogenous exergy destruction. It is apparent that the sum of endogenous and exogenous exergy destruction is equal to the total exergy destruction within the component being considered. Knowledge of the exogenous and endogenous exergy destruction for the most important components can further assist the engineer in deciding whether an adjustment in that component or in the structure of the system (i.e. in the remaining components) is required to improve the overall system. The paper presents the general concept of endogenous and exogenous exergy destruction. Using a graphical approach, the endogenous and exogenous exergy destruction of a simple gas turbine process and simple refrigeration machine are investigated.

Polityka klimatyczno-energetyczna Unii Europejskiej

2014 ◽  
pp. 104-121
Author(s):  
Aleksandra Kułaga
Keyword(s):  
Negative Impact ◽  
Renewable Energy Sources ◽  
Energy System ◽  
The Other ◽  
Energy Sources ◽  
Climate Protection ◽  
The European Union ◽  
Eu Member States ◽  
The Subject ◽  
Climate And Energy Policy

The article is devoted to the subject of the goals of the climate and energy policy of the European Union, which can have both a positive, and a negative impact on the environmental and energy policies. Positive aspects are the reduction of greenhouse gas emissions, diversification of energy supplies, which should improve Europe independence from energy imports, and increasing the share of renewable energy sources (RES) in the national energy system structures. On the other hand, overly ambitious targets and actions can lead to large losses for the economies of EU Member States. The article also highlights the realities prevailing in the international arena and noncompliance of international actors with global agreements on climate protection.

scholarly journals 4E Analysis of a Fuel Cell and Gas Turbine Hybrid Energy System

2020 ◽  
Vol 11 (1) ◽  
pp. 7568-7579
Keyword(s):  
Fuel Cell ◽  
Cell Voltage ◽  
Energy System ◽  
High Energy ◽  
Exergy Efficiency ◽  
Combined Cycle ◽  
Net Energy ◽  
Exergy Destruction ◽  
Molten Carbonate ◽  
Ambient Temperatures

Exergy analysis of the expansion turbine hybrid cycle of integrated molten carbonate fuel cells is presented in this study. The proposed cycle was used as a sustainable energy curriculum to provide a small hybrid power plant with high energy efficiency. To generate electricity with the system mentioned above, and externally repaired fusion carbon fuel cell was used located at the top of the combined cycle. Moreover, the turbine and steam turbine systems are considered as complementary and bottom layers for co-generation, respectively. The results showed that the proposed system could reach net energy of up to 1125 kilowatts, while the total exergy efficiency (including electricity and heat) for this system is more than 68%. Moreover, the energy supplied and exergy efficiency derived from the proposed cycle are stable versus changes in ambient temperatures. Besides, the effect of increasing the current density on the cell voltage and the total exergy destruction was considered. Also, the new approaches of the exergoeconomics and exergoenvironmental analysis are implemented in this system. The results show that the hybrid system can decrease the exergy destruction costs more than 16%, and the environmental footprint of the system more than 23.4%.

scholarly journals Analysis of the Effects of Electrification of the Road Transport Sector on the Possible Penetration of Nuclear Fusion in the Long-Term European Energy Mix

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3634
Author(s):  
Daniele Lerede ◽  
Chiara Bustreo ◽  
Francesco Gracceva ◽  
Yolanda Lechón ◽  
Laura Savoldi
Keyword(s):  
Power Plants ◽  
Nuclear Fusion ◽  
Energy System ◽  
Road Transport ◽  
The Other ◽  
Electricity Production ◽  
Transport Sector ◽  
Consumption Pattern ◽  
Deep Penetration ◽  
The Road

The European Roadmap towards the production of electricity from nuclear fusion foresees the potential availability of nuclear fusion power plants (NFPPs) in the second half of this century. The possible penetration of that technology, typically addressed by using the global energy system EUROFusion TIMES Model (ETM), will depend, among other aspects, on its costs compared to those of the other available technologies for electricity production, and on the future electricity demand. This paper focuses on the ongoing electrification process of the transport sector, with special attention devoted to road transport. A survey on the present and forthcoming technologies, as foreseen by several manufacturers and other models, and an international vehicle database are taken into account to develop the new road transport module, then implemented and harmonized inside ETM. Following three different storylines, the computed results are presented in terms of the evolution of the road transport demand in the next decades, fleet composition and CO 2 emissions. The ETM results are in line with many other studies. On one hand, they highlight, for the European road transport energy consumption pattern, the need for dramatic changes in the transport market, if the most ambitious environmental goals are to be pursued. On the other hand, the results also show that NFPP adoption on a commercial scale could be justified within the current projection of the investment costs, if the deep penetration of electricity in the road transport sector also occurs.

Reinforcement of Polymers. I. Tear Resistance of Filled Mixes and Adhesion of Elastomer to Filler as a Function of Duration and Temperature of Elastomer and Filler Contact

1968 ◽  
Vol 41 (3) ◽  
pp. 601-607
Author(s):  
V. G. Raevskii ◽  
S. M. Yagnyatinskaya ◽  
S. N. Episeeva ◽  
S. S. Voyutskii
Keyword(s):  
Experimental Data ◽  
Tensile Strength ◽  
Surface Crack ◽  
General Type ◽  
Physicomechanical Properties ◽  
The Other ◽  
Local Defect ◽  
System Components ◽  
Selection Of ◽  
Tear Resistance

Abstract In accordance with the concepts being developed by the authors of the present paper, the influence of fillers on the properties of filled systems is determined by adhesion of the polymer to the filler. There are indications of the significance of this factor in many papers dealing with the study of reinforcement. However, they do not advance adhesion as a basic factor which determines reinforcement. This has become possible after the development of a procedure for the evaluation of adhesion of polymers to powdered fillers. This paper lists experimental data on the correlation between the duration and temperature of contact of the elastomer with filler particles on the tear resistance of filled mixes, on one hand, and the time and temperature dependence of the adhesion of the system components to one another, on the other. The selection of tear resistance as a characteristic of the physicomechanical properties of the system is governed by the fact that failure starts, as a rule, from a random local defect. Most frequently this is a small cut or surface crack. For this reason, the assertion of a number of researchers that the operating properties of products are more fully characterized by tear resistance rather than by tensile strength is fully acceptable. Besides, tearing is the most general type of destruction of materials, inasmuch as it takes place during rupture as well as during wear.

Man-Machine Photogrammetric Systems and System Components

1973 ◽  
Vol 27 (4) ◽  
pp. 308-319 ◽  
Author(s):  
Z. Jaksic
Keyword(s):  
Data Processing ◽  
Research Council ◽  
Communication Theory ◽  
National Research Council ◽  
The Other ◽  
System Components ◽  
Two Systems ◽  
Machine Systems

Under the influence of ideas from control and communication theory, new trends have developed in the design of photogrammetric data-processing systems. In this paper a number of concepts applied to the design of such systems are discussed, with emphasis on the digital man-machine systems and system components. The main characteristics of contemporary photogrammetric systems are outlined in regard to both their hardware and software, including some remarks on automation and orthophototechniques. The general descriptions are supported by examples from two systems: one predominantly digital and the other predominantly analog. These examples concern the instrumental developments in the Photogrammetric Research Laboratories of the National Research Council of Canada.

scholarly journals Techno-Economic Analysis of Grid-Connected PV and Fuel Cell Hybrid System Using Different PV Tracking Techniques

2020 ◽  
Vol 10 (23) ◽  
pp. 8515
Author(s):  
Saif Mubaarak ◽  
Delong Zhang ◽  
Yongcong Chen ◽  
Jinxin Liu ◽  
Longze Wang ◽  
...  
Keyword(s):  
Hybrid System ◽  
Energy Systems ◽  
Energy System ◽  
Vital Role ◽  
Pv System ◽  
Hybrid Energy ◽  
Cost Of Energy ◽  
System Components ◽  
Pv Generation

Solar energy has attracted the attention of researchers around the world due to its advantages. However, photovoltaic (PV) panels still have not attained the desired efficiency and economic mature. PV tracking techniques can play a vital role in improving the performance of the PV system. The aim of this paper is to evaluate and compare the technical and economic performance of grid-connected hybrid energy systems including PV and fuel cells (FC) by applying major types of PV tracking technique. The topology and design principles and technical description of hybrid system components are proposed in this paper. Moreover, this paper also introduces economic criteria, which are used to evaluate the economy of different PV tracking techniques and seek the optimal configuration of system components. In the case study, the results show that the vertical single axis tracker was ranked 1st in terms of highest PV generation, penetration of renewable energy to the grid, lowest CO2 emission, highest energy sold to the grid and lowest purchased, and lowest net present cost (NPC) and levelized cost of energy (LCOE). The study found that the optimal design of a grid-connected hybrid energy system (PV-FC) was by using a vertical single axis tracker which has the lowest NPC, LCOE.

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