EXERGY ANALYSIS

EXERGY ANALYSIS

Exergy analysis is a formalised way of applying availability theory to engineering
installations such as power generating plants. Energy (First Law) analysis keeps track of the
heat and work transfers but does not indicate the source and magnitude of the irreversible
entropy creation. Exergy (Second Law) analysis provides this information. It is useful in
indicating where research resources can be directed to best advantage.

Exergy Calculation

Exergy Calculation

This chapter is intended to give the user a better knowledge of exergy calculations in Cycle-Tempo.
Exergy is not an absolute quantity but a relative one. Therefore, to say something about it, it must be
known to which exergy level the calculation must be compared with. In Cycle-Tempo the exergy
calculations are based on the chosen environment conditions. So, it is necessary to set the environment
conditions in Cycle-Tempo or else an exergy calculation will not be made. Throughout this chapter the
environment is chosen to be like that of Baehr at 25o C.

References Combined Cycle Power Plants

Enso Española SA, Combined cycle power plant, Castellbisbal, Spain

50 MWe/25 MWth, LM6000 gas turbine with DLEcombustion, HRSG with ambient air firing, extraction/condensing steam turbine, hybrid cooling tower plant,chilling plant for gas turbine inlet air cooling.
Fuel: natural gas
Project management, feasibility studies, conceptualdesign, procurement services, process engineering,water treatment engineering, plant layout, automationengineering, automation detailed design and super-vision, electrical engineering, piping design, structuraldesign, HVAC engineering, house electrification basicdesign, permits and licences, architectural design,time scheduling services, site supervision, generaltraining, acceptance tests and GT plant maintenanceprocurement, 1996Detailed project description (PDF 2659 kB)

Ca Mau 720 MW gas-fired combined cycle powerplant,

Vietnam

The combined cycle power plant consists of twoF-technology gas turbine generator units, each240 MW, two HRSGs and one steam turbine gener-ator unit, with all associated auxiliary equipmentand support facilities.
Fuels: natural gas, fuel oil
Additional soil investigation, review of feasibilitystudy, preparation of conceptual design, preliminarydesign, investment cost estimate and EPC specific-ations, additional civil design for material take-off, design of electrical and SCADA/Telecommuni-cation interconnection with National Power System,support in approval process, 2003-2004Detailed project description (PDF

Jandar combined cycle power plant,Syrian Arab Republic

700 MWe combined cycle power plant, 4x118MWe MW701 gas turbines, 2 x 114 MWe condensingsteam turbine, air cooled condenser
Fuels: natural gas, refinery gas and fuel oil
Complete project management and implementationsupervision of turnkey delivery: design, engineering,manufacturing and assembly. Civil works, erection,commissioning, test runs, guarantee period, train-ing, 1995Detailed project description (PDF 1562 kB)68 kB)

Combined cycle district heating power plantDonaustadt 3, Vienna, Austria

350 MWe/250 MWth combined cycle. Single shaftarrangement with each one 250 MW gas turbineand 100 MW steam turbine. Engineering services,basic design, petitioning in accordance with theEIS, invitation to bid on an EPC basis, bid evalu-ation, contracting, quality assurance, construc-tion and erection supervision, overall coordin-ation and assistance during guarantee period,1997-2004

District heating Plant "Mitte", Salzburg, Austria

80 MWe/120 MWth combined cycle power plantwith 2-pressure heat recovery boiler, heavyfuel fired stand-by boiler, basic design, technicalspecification, EIS documents, assistance duringpermitting phase, preparation of tender docu-ments, tender evaluation, overall coordinationand elaboration of detailed solutions, acceptancetests, 1993-2003

Naistenlahti combined cycle power plant, Tampere,Finland

127 MWe/140 MWth (DH), HSRG supplementaryfired, gas turbine + existing steam turbine
Fuels: natural gas and LFO
Project management, feasibility studies, conceptualdesign, procurement services for gas turbineand HRSG, process engineering, water treatmentengineering and procurement, plant layout, auto-mation and electrical engineering and procurement,piping design, structural design, HVAC engineering,house electrification basic design, time schedulingservices, GT plant maintenance procurement, 2000Detailed project description (PDF 2460 kB)

Kirkniemi combined cycle power plant, Finland

110/115 MWe, 115/170 MWth combined cycle,frame 6FA gas turbine with DLN combustion, HRSGwith supplementary and fresh air firing, processextraction/ condensing steam turbine
Fuels: natural gas and LFO
Feasibility studies, conceptual engineering, mainprocess engineering, procurement services for gasturbine, HRSG and steam turbine, architecturaldesign, automation consulting services and GT plantmaintenance specifications, 1997Detailed project description (PDF 2674 kB)

Nokian Lämpövoima Oy, Combined Cycle PowerPlant, Tampere, Finland

65 MWe/60 MWth, frame 6B gas turbine with DLNcombustion, HRSG with two steam pressure levelsand supplementary firing, extraction/condensingsteam turbine
Fuels: natural gas and LFO
Project management, feasibility studies, procurementservices for gas turbine, HSRG, steam turbine andauxiliaries, process and conceptual design, auto-mation engineering, piping design, plant layout,general training and GT plant maintenance specific-ations, 1996-1997Detailed project description (PDF 2004 kB)

Talkha power plant

Talkha power plant is

the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile (208 m3 /h). The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply (100 m3/h) and for water demineralization supply (108 m3/h).

Energy–exergy analysis and modernization suggestions

Energy–exergy analysis and modernization suggestionsfor a combined-cycle power plantEnergy and exergy analysis were carried out for a combined-cycle power plant by using the data taken fromits units in operation to analyse a complex energy system more thoroughly and to identify the potential forimproving efficiency of the system. In this context, energy and exergy fluxes at the inlet and the exit of thedevices in one of the power plant main units as well as the energy and exergy losses were determined. Theresults show that combustion chambers, gas turbines and heat recovery steam generators (HRSG) are themain sources of irreversibilities representing more than 85% of the overall exergy losses.

Integrated Gasification Combined Cycle
(IGCC)

Combined cycle is a term used when a power producing engine or plant employs more than one thermodynamic cycle. Heat engines are only able to use a portion of the energy their fuel generates (usually less than 30%). The remaining heat from combustion is generally wasted. Combining two or more "cycles" such as the Brayton cycle and Rankine cycle results in improved overall efficiency.