EXERGY AND THERMOECONOMIC ANALYSES OF SOLAR AIDED THERMAL POWER PLANTS WITH THERMAL STORAGE ADIBHATLA SAIRAM

Transcription

1 EXERGY AND THERMOECONOMIC ANALYSES OF SOLAR AIDED THERMAL POWER PLANTS WITH THERMAL STORAGE ADIBHATLA SAIRAM CENTRE FOR ENERGY STUDIES INDIAN INSTITUTE OF TECHNOLOGY DELHI HAUZ KHAS, NEW DELHI , INDIA APRIL, 2017

2 Indian Institute of Technology Delhi (IITD), New Delhi, 2017

3 EXERGY AND THERMOECONOMIC ANALYSES OF SOLAR AIDED THERMAL POWER PLANTS WITH THERMAL STORAGE by ADIBHATLA SAIRAM Centre for Energy Studies Submitted in fulfillment of the requirements of the degree of Doctor of Philosophy to the INDIAN INSTITUTE OF TECHNOLOGY DELHI HAUZ KHAS, NEW DELHI , INDIA APRIL, 2017

4 Dedicated to Lord Guru Dattatreya

5 CERTIFICATE This is to certify that the thesis entitled EXERGY AND THERMOECONOMIC ANALYSES OF SOLAR AIDED THERMAL POWER PLANTS being submitted by ADIBHATLA SAIRAM to the INDIAN INSTITUTE OF TECHNOLOGY, DELHI for the award of the degree of DOCTOR OF PHILOSOPHY is a record of bonafide research work carried out by him under my guidance and supervision. He has carried out his research work at Centre for Energy Studies, I.I.T. Delhi. The results obtained here in have not been submitted in part, or in full, to any other University or Institute for the award of any degree or diploma to the best of my knowledge. Supervisor Dr. S. C. KAUSHIK Professor Centre for Energy Studies Indian Institute of Technology Hauz Khas, New Delhi , India E- mail: Kaushik@ces.iitd.ac.in i

6 ACKNOWLEDGEMENT I express my deep sense of gratitude to thesis supervisor Dr. S. C. Kaushik, Professor, Centre for Energy Studies, IIT Delhi for his overall guidance, painstaking efforts, dynamic supervision and deep interest in research work without which this thesis would not have reached the present stage. I am thankful to my spiritual guru and almighty lord Dattatreya whose blessings have given me immense confidence and mental strength throughout my research work. I am also grateful to Director, IIT Delhi and Head, Centre for Energy Studies, IIT Delhi for providing the necessary facilities in completing this work and for giving me an opportunity for higher learning. The motivation and inspiration provided by SRC members and faculties and all staff members of Centre for Energy Studies is also duly acknowledged. I am thankful to my employer NTPC Limited, a Maharatna Central Public Sector Undertaking Company of Government of India and a great learning organization for giving me permission for higher studies. I thank from deep inside of my heart to my research colleagues specially Sh. Mani Kandan and members of the solar thermal science laboratory at Centre for Energy Studies, IIT Delhi. Last but not least, words alone cannot express my deepest gratitude for the constant support, understanding, and encouragement for reaching this position from my family members. (Adibhatla Sairam) iii

7 ABSTRACT The global energy demand is increasing continuously every year whereas the fossil fuel resources are dwindling at a faster rate. Besides this, the pollution and greenhouse gasses associated with combustion of fossil fuel resources are creating environmental hazards. Although the advent of super critical technology has helped in an effective utilization of coal, still the issue of emissions remains unanswered. This situation has made the energy community to venture into power generation using renewable energy sources (RES). Among the RES, solar energy has emerged as a viable option due to its clean, free and abundant nature. Solar energy can be converted into electricity either through solar photovoltaic (PV) or solar thermal technology. However, for large scale grid connected power generation, solar PV is not suitable and hence solar thermal means is preferred over the solar PV. Within the solar thermal power generation, one can go for either solar alone or solar aided means. However due to low source temperatures, thermal efficiency of solar alone plants is very low. Besides the capital costs of solar alone plants are high and capacity utilization factors are low due to frequent plant start-up and shut downs. The solar aided power generation has the advantage of higher solar to electricity conversion efficiencies relative to solar alone due to the fact that solar heat is not effecting the source temperature of the cycle. It is assuming a greater importance due to its flexibility in integrating with conventional coal fired steam plants and gas fired combined cycle power plants. This thesis is an attempt to develop such integrated solar aided cycle (s) and study their performance, economic viability and cost rates of product streams using exergy, economic and thermoeconomic principles. The integration of solar energy with both coal fired (sub critical and super critical) Rankine cycle based steam power plants and gas fired combined cycle power plants has v

8 been studied in this thesis. The reference coal fired power plants considered for the study are a 500 MWe sub critical and 660 and 800 MWe super critical thermal power plants. The first two coal fired power plants are operating in India whereas the 800 MWe unit is under construction/commissioning. The reason for choosing different capacity units is to study the effect of unit heat rate on LCoE and simple payback periods with solar aided feed water heating. The reference combined cycle power plant is a dual pressure cycle operating in India. Design data as given in the heat balance diagrams of above mentioned plants has been used in the study. The thermal energy storage option is also considered in this thesis by increasing the solar field aperture area sufficient enough to meet the heater load at full load for seven hours. Engineering Equation Solver (EES), 2010 has been used for carrying out energy, exergy and thermo economic analysis of power plants under study. Energy, exergy, economic and environmental (4E) analysis has been performed on a conceptual cycle where in solar aided feed water heating (SAFWH) has been integrated with reference modified Rankine cycle based power plants. The conventional power plants chosen for the 4E analysis are 500/660/800 MWe coal fired thermal power plants. Performance parameters (energy, exergy efficiency, unit heat rates, fuel saving and solar contribution), economic parameters (Levelised cost of electricity generation, payback period) and environmental parameters (reduction in coal, CO2 and ash generation) have been calculated for SAFWH in each feed water heater except LP Heater-1 and deaerator. The results have shown that the LCoE and payback periods are the least for SAFWH in HP Heater-7. The 4Eanalysis has been performed in all cases under fuel saving mode. Sensitivity analysis has been done to find out the variation in LCoE with respect to discount rate, plant capacity factor and fuel cost. vi

9 Energy and exergy analysis has been performed on a 660 MWe super critical coal fired thermal power plant at various load conditions (100%, 80% and 60% of normal continuous rating) under constant and pure sliding pressure operation. From this analysis, it has been observed that boiler has the highest exergy destruction rate than any other component of the power plant. Also, it has been observed that the rate of exergy destruction and boiler feed pump power input reduces greatly at part loads with sliding pressure operation than the constant pressure operation. Exergy and thermo economic analysis has been performed on a 500/660 MWe coal fired thermal power plants without and with solar aided feed water heating with an objective to find out the costs of different product streams emanating from major plant equipment. A feed water heat exchanger (FWHE) has been placed parallel to the stream of high pressure feed water heater (HPH s) for feed water heating so that the bleed steam going to all HPH s is completely substituted by solar heating. The results of the exergy analysis have revealed that the exergetic efficiency is lowest in the solar field followed by the boiler. The thermoeconomic analysis of the integrated plants has revealed the cost rates of the product streams in the cycle. These cost rates have taken the capital cost of the equipment in to consideration. Energy, exergy and economic (3E) analyses have been performed on an integrated cycle consisting of a combined cycle power plant and a solar field for direct steam generation using medium temperature integration. Solar aided preheating and evaporation of high pressure feed water has been assumed to be taking place in the solar field. High pressure feed water has been taken from the HP Economizer 1 outlet of both heat recovery steam generators (HRSG) for preheating and evaporation in the solar field. The steam leaving the solar field at design point is assumed to be dry saturated. However, off design operation vii

10 may yield wet steam. Hence, a separator vessel has been provided at the end of evaporator section of the solar field for separating the water from the steam. Dry saturated steam leaving the separator is mixed with the steam leaving the high pressure (HP) drum before it enters the HP super heater section of the HRSG. No solar aided heating has been envisaged in the low-pressure circuit. As solar integration, has been done in the bottoming cycle, the cycle parameters at salient points and performance of the gas turbine plant have been assumed to be unchanging. Also, the pressures and temperatures of the steam plant have been assumed to be same as that of reference plant. However, the mass flow rates do change, which are calculated by applying mass and energy balance for the entire bottoming steam cycle. A detailed thermodynamic model has been developed for the HRSG and steam plant for finding the thermodynamic properties of the working fluid at salient points of the integrated cycle prior to performing the 3E analysis. Energy, exergy and economic (3E) analyses have been performed on an integrated cycle consisting of a combined cycle power plant using a solar operated vapor absorption chiller (SVAC) for gas turbine inlet air cooling. This cycle is referred as integrated combined cycle with solar vapor absorption chiller (ICCSVAC). Exergy analysis performed on the ICCSVAC has revealed that the exergetic efficiency is lowest in the solar field (collector-receiver system) followed by the combustion chamber. An increase in net plant output from MWe to MWe has been observed in this study by decreasing the compressor inlet temperature from K to K. However, this is possible with increase in size of gas turbine (GT) plant, steam turbine (ST) and heat recovery steam generator (HRSG) involving additional capital expenditure. The economic analysis reveals that this additional capital expenditure is justified in view of surplus cash inflows for the generator. So, this technology viii

11 seems to have great potential for those areas where solar conditions are favourable with high ambient temperatures throughout the year. This thesis as a whole will provide a holistic approach for integrating solar energy for preheating the feed water in an existing (retrofit) or new power plant with an objective to move towards greener power generation. The present study is also useful for the actual design and development of the solar aided combined cycle power plant. ix

12 lkjka k व श ववक ऊर ज क मज ग हर सजल लगजतजर बढ रह ह र बकक र वजवम ई धन स सजधन त र स बढ रह ह इसक अलजवज, प रद षण और र वजवम ई धन स सजधन क दहन स र ड ग र नहजउस ग स पर ज वरण क खतर कज ननमज ण कर रह ह हजलज कक स पर महत वप ण प र द र गगक क आगमन स क र ल कज प रभजव उपर ग करन म मदद ममल ह, क र भ उत सर न कज म द दज अभ भ उत तर नह द तज ह इस श थ नत न ऊर ज सम दजर क अक षर ऊर ज स र त (आरईएस) कज उपर ग करक बबर ल उत पजदन म उद र म बनजर ज ह आरईएस म स, स र ऊर ज अपन थवच छ, थवत त र और प रच र मजत रज म प रक नत क कजरण एक व र वहजर ववकल प क र प म उभरज ह स र ऊर ज क स र ट व श ल टक (प व ) र ज स र तजप र प र द र गगक क मजध र म स र ज त बबर ल म पररवनत त ककर ज र ज सकतज ह हजलज कक, बड प मजन पर गग रड स र ड ववद र त उत पजदन क मलए, स र प व उपर क त नह ह और इसमलए स र प व क ऊपर स र तजप र सजधन पस द ककर ज र जतज ह स र तजप र बबर ल उत पजदन क भ तर, क ई भ अक ल र ज स र सहजर तज प रजप त सजधन क मलए र ज सकतज ह हजलज कक, कम स र त तजपमजन क कजरण, स र अक ल प ध क तजप र दक षतज बह त कम ह स र अक ल प ध क प र गत लजगत क अलजवज अगधक ह और लगजतजर स र त र श र ह न और शट डजउस क कजरण क षमतज उपर ग क कजरक कम ह स लर गर म चक र क स र त क त पर म न क प रभ व त नह कर रह ह, इसललए स र सह यत प र प त व द य त उत प दन र म अक ल स र ऊर क स ब ध र म व द य त र प तरण क षर मत क ललए उच च स र क ल भ ह त ह पर पर गत क यल भ प ल भ प ल प ध और ग स स र ड स य क त चक र व द य त स य त र क स थ एक क त करन र म इसक लच ल पन क क रण यह अधधक र महत ग रहण कर रह ह यह श ध इस तरह क एक क त स र सह यत प र प त चक र (एस) क व कलसत करन और उनक प रदश न, आधथ क व य ह य त और उत प द प र ह क ल गत दर क अध ययन करन क प रय स ह, र कक प दर, आधथ क और त प य लसद त क उपय ग करत ह द न क यल स ननक ल ददय गय स र ऊर क एक करण (उप र महत प ण और स पर कक रद कल) र ककन चक र आध ररत ष प व द य त स य त र और ग स स र ड स य क त चक र व द य त स य त र क अध ययन इस श ध र म ककय गय ह अध ययन क ललए र म न र न ल स दभ क यल स ननक ल ददय गय बबर ल स य त र 500 र म ग सब र महत प ण और 660 xi

13 और 800 र म ग स पर कक रद कल थर म ल प र प ल ह पहल द क यल ननक लकर प र प ल भ रत र म क र म कर रह ह र बकक 800 र म ग इक ई ननर म ण / कर म शन क तहत ह अलग-अलग क षर मत इक इय क च नन क क रण एलस ओई पर य नन गर म दर क प रभ और स र सह यत प र प त फ ड र ह द ग क स थ सरल पस अ धध क अध ययन करन ह स दभ स य क त चक र व द य त स य त र भ रत र म द हर दब चक र ह अध ययन र म ऊपर र ण त प ध क गर म श ष आर ख र म ददए गए डडज इन ड क उपय ग ककय गय ह त प य ऊर भ ड रण व कल प क इस श ध र म भ र म न र त ह र स त घ तक प र ल ड पर ह र ल ड क प र करन क ललए पय प त पय प त स र क ष त र एपच र क ष त र बढ कर र म न र त ह इ र ननयरर ग सर म करण स ल र (ईईएस), 2010 क उपय ग अध ययन क तहत व द य त स य त र क ऊर, व द य त और थर म र म र आधथ क व श ल षण क ललए ककय गय ह ऊर, ऊर, आधथ क और पय रण य (4 ई) व श ल षण एक स कल पन त र मक चक र पर ककय गय ह र ह स र अन द ननत फ ड र ल त प (एसएएफडब लल य एच) क स श धधत र न इन चक र आध ररत बबर ल स य त र क स थ एक क त ककय गय ह 4 ई व श ल षण क ललए च न र न ल प र पररक प र प ल 500/660/800 र म ग क यल ननक लकर थर म ल प र प ल लग ए गए ह प रदश न र म पद ड (ऊर, प दप दक षत, य नन गर म दर, ई धन बचत और स र य गद न), आधथ क प र र म र (बबर ल उत प दन क परत ल ल गत, ल न क अ धध) और पय रण य र म नक (क यल, स ओ 2 और र ख प ढ र म कर म ) क गणन एसएएफडब लल य एच क ललए क गई ह प रत य क फ ड र ह र एलप ह र -1 और ड र र क छ डकर पररण र म ददख त ह कक एचस ह र -7 र म एलओस ओ और ल न क अ धध एसएएफडब लल य एच क ललए सबस कर म ह 4 एन लललसस ई धन बचत र म ड क तहत सभ र म र मल र म ककय गय ह छ दर, स य त र क षर मत क रक और ई धन ल गत क स ब ध र म एलस ओई र म लभन नत क पत लग न क ललए स दनश लत व श ल षण ककय गय ह न र तर और श द स ल इड ग दब व ऑपर श क तहत ववभ न ल पररस स नतय (100%, 80% और स म न य न र तर र ट ग क 60%) पर 660 म ग व स पर क र ट कल क यल पर ऊर और एस जर ववश ल षण क रकय गय ह इस ववश ल षण स, यह प य गय ह क रक बबर ल स य त र क क रकस अन य घ क क त ल म ब यलर म xii

14 उच चतम प भलस वव श दर ह इसक अल व, यह द ख गय ह क रक ब हर दब व और ब यलर फ प प क प वर इ प क दर न र तर दब व ऑपर श क त ल म क रफसल दब व ऑपर श क स ग र म बह त कम ह र त ह एक स र और थर म आधथ क व श ल षण 500/660 र म ग क यल पर ककय गय ह र कक त प य ऊर स य त र क बबन और बड प ध क उपकरण स ननकलन ल व लभन न उत प द ध र ओ क ल गत क र नन क ललए स र सह यत प र प त फ ड र ल त प क स थ ककय गय ह फ ड र ह एक सच र र (एफडब लल य एचई) क उच च दब ल फ डर र ह र (एचप एच) क प न क प न क ललए सर म न तर रख गय ह त कक सभ एचप एच क ललए ख न भ प प र तरह स स र ह द ग द र प रनतस थ वपत ककय र सक एक क र व श ल षण क पररण र म स पत चल ह कक ब यलर द र प छ ककए र न ल स र क ष त र र म सबस त र ऊर दक षत ह एक क त प ध क उष र म ककक व श ल षण न चक र र म उत प द ध र ओ क ल गत दर क पत चल ह इन ल गत दर न उपकरण क प र गत ल गत क ध य न र म रख ह ऊर, प र र और आधथ क (3 ई) क व श ल षण एक एक क त चक र पर ककय गय ह क र सर म एक स य क त चक र व द य त स य त र और र मध यर म त पर म न एक करण क उपय ग करत ह ए स ध ष प उत प दन क ललए एक स र क ष त र श लर मल ह स र सह यत प र प त प र ह द ग और उच च दब ल प न क ष प करण क स र क ष त र र म लग य र रह ह एचप अथ र क स उच च दब ल प न क प न ललय गय ह - स र क ष त र र म प र ह द ग और ष प करण क ललए गर म ररक र स र म र नर र (एचआरएसर ) द न क एक आउ ल स र बब द क डडर इन बब द पर छ डन ल भ प क स ख स त प त र म न र त ह ह ल कक, डडज इन क स च लन स ग ल भ प ननकल सकत ह इसललए, ष प स र ल क अलग करन क ललए स र क ष त र क ब ष प करण अन भ ग क अ त र म एक व भ र क र ह र ददय गय ह स क ष र म स त प त भ प व भ र क छ डन स भ प क स थ लर मल य र त ह क र सस एचआरएसर क एचप स पर ह र ख ड र म प र श करन स पहल उच च दब (एचप ) ड रर म छ ड र त ह ननम न-दब सकक र म क ई स र सह यत प र प त ह द ग क अन र म न नह ककय गय ह स र एक करण क र प र म, त ल चक र र म ककय गय ह, र म ख य बब द ओ पर चक र र म पद ड और ग स रब इन स य त र क प रदश न क xiii

15 अपरर त न य र म न गय ह इसक अल, भ प स य त र क दब और त पर म न क स दभ प ध क सर म न र म न र त ह ह ल कक, बड प र म न पर प र ह दर र म परर त न ह त ह, र कक प र तह तक भ प चक र क ललए द रव यर म न और ऊर स त लन लग न क द र गणन क र त ह 3 ई व श ल षण करन स पहल एक एक क त चक र क प रर म ख बब द ओ पर क य श ल तरल पद थ क थर म ड यन लर मक ग ण क ख र न क ललए एचआरएसर और स र म प ल क ललए एक व स त त उष र म यननक र म डल व कलसत ककय गय ह ग स रब इ इ ल एयर क भल ग क भलए एक स र स च भलत व ष प अवश षण चचलर (एसव एस ) क उपय ग करत ह ए एक स य जत च ववद य त स य त र स भमलकर एक एक क त च पर ऊर, प र र और आच क (3 ई) क ववश ल षण क रकय गय ह इस च क स र व ष प अवश षण चचलर (आईस स एसव एस ) क स एक क त स य जत च कह र त ह आईस स एसव एस पर न ष प टदत एजस ग ववश ल षण स पत चल ह क रक दह कक ष द व र प छ क रकए र व ल स र क ष त र (कल ज र-ररस वर भसस म) म सबस त र ऊर दक षत ह क प र सर इ ल त पम क जय स क स तर तक घ कर इस अध यय म म ग व स म ग व स श द स य त र उत प द म व वद द ख गई ह ह ल क रक, यह ग स रब इ (र ) स य त र, स म रब इ क आक र म व वद क स स व ह (एस ) और गम वस ल प र र र (एचआरएसर ) अनतररजत प र व यय क श भमल आच क ववश ल षण स पत चलत ह क रक र र र क भलए अच श ष कद प रव ह क द खत ह ए यह अनतररजत प र गत खच उचचत ह इसभलए, इस तक क क उ इल क क भलए क फ स व ए ह र ह स र वष प र व त वरण म उच च पररव श क त पम क अ क ल ह प र क र प म यह भसस हररय ल बबर ल उत प द क भलए आग बढ क उद श य स एक म र द (र ट र फ इ ) य ए बबर ल स य त र म फ व र क गरम कर क भलए स र ऊर क एक क त कर क भलए एक समग र द स ष क ण प रद कर ग वत म अध यय स र सह यत प र प त स य जत च ववद य त स य त र क व स तववक ड र इ और ववक स क भलए उपय ग ह xiv

16 Certificate Acknowledgement Abstract Abstract in Hindi Contents List of figures List of tables Nomenclature CONTENTS Chapter-1: Introduction Background Global and Indian power generation scenario Solar alone power generation Solar aided power generation (SAPG) Solar aided feed water heating (SAFWH) in coal fired power plants Integrated solar combined cycle power plants (ISCCPP) Basis of energy and exergy analysis Basis of economic and thermoeconomic analysis Objectives of the thesis Methodologies Scope of the thesis Organization of thesis Chapter-2: Energy, exergy, economic and environment (4E) analyses of a solar aided 500 MWe sub critical coal fired thermal power plant i iii v xi xv xix xxiii xxvii 2.1 Introduction and literature survey Solar aided feed water heating (SAFWH) Description of reference 500 MWe thermal power plant Energy and exergy analysis of reference 500 MWe power plant Assumptions made in integrating solar energy for feed water heating 40 with the reference plant 2.6 Selection of heat transfer fluid Mechanical integration of solar field with reference plant Methodology Simulation of solar field Equivalent working hours (EWH) Performance parameters Economic analysis with thermal energy storage Estimation of capital costs Calculation of annualized and levelised cost of electricity generation 54 xv

17 2.13 Reductions in coal consumption, CO2 emissions and ash generation with 59 thermal energy storage 2.14 Results & discussion Conclusions Chapter-3: Exergy and thermoeconomic analyses of 500 MWe sub critical thermal power plant with solar aided feed water heating 3.1 Introduction and literature survey Description of conceptual solar aided 500 MWe thermal power plant Exergy analyses of reference and integrated plants Thermoeconomics Thermoeconomic parameters Physical model of reference and integrated power plants Productive structure of reference and integrated power plants Characteristic equations for each plant unit Capital costs of plant equipment Calculating costs of flows in the productive structure Thermoeconomic equations for plant units of 500 MWe thermal power 91 plant 3.12 Thermoeconomic equations for plant units of solar aided 500 MWe 94 thermal power plant 3.13 Results & discussions Exergy analysis Thermoeconomic Analysis Conclusions 102 Chapter-4: Energy and exergy analysis of a super critical thermal power plant at various load conditions under constant and pure sliding pressure operation 4.1 Introduction and literature survey System description of 660 MWe coal fired super critical power plant Energetic analysis of the 660 MWe super critical TPP Exergetic analysis of the 660 MWe super critical TPP Energetic and exergetic analysis of the plant under constant pressure 121 operation 4.6 Energetic and exergetic analysis of the plant under sliding pressure 129 operation 4.7 Comparison of results of energetic and exergetic analysis between 136 constant pressure and pure sliding pressure operation 4.8 Conclusions Chapter-5: Energy, exergy, economic and environment (4E) and thermoeconomic analysis of a solar aided super critical coal fired thermal power plants 5.1 Introduction Description of 660 MWe super critical thermal power plant Simulation of solar field Economic analysis with and without thermal energy storage xvi

18 5.5 Reductions in coal consumption, CO2 emissions and ash generation 145 without and with thermal energy storage 5.6 Results & discussion E analysis of solar aided 800 MWe super critical unit Reductions in coal consumption, CO2 emissions and ash 160 generation without and with thermal energy storage Results & discussion Exergy and thermoeconomic analyses of 660 MWe thermal power plant with solar aided feed water heating Description of conceptual solar aided 660 MWe thermal power 171 plant Exergy analyses of reference and integrated plants Physical model of reference and integrated power plants Productive structure of reference and integrated power plants Capital costs of plant equipment Thermoeconomic equations for plant units of 660 MWe thermal 179 power plant Thermoeconomic equations for plant units of solar aided MWe thermal power plant with thermal energy storage Results & discussion Conclusions Chapter-6: Energy, exergy and economic (3E) analysis of integrated direct steam generation combined cycle power plant and combined cycle power plant integrated with solar cooling of gas turbine inlet air 6.1 Introduction and literature survey Description of proposed DSG ISCC plant Solar field integration with RCCPP Thermodynamic model for heat recovery steam generator Effective working hours (EWH) Performance parameters Energy and exergy analysis of DSG ISCCPP Results & discussion Energy and exergy analysis Performance analysis Economic analysis of DSG ISCCPP Energy, exergy and economic analyses of combined cycle power plant integrated with solar cooling of gas turbine inlet air Introduction and literature survey Description of integrated combined cycle with solar vapour 221 absorption chiller (ICCSVAC) Effective working hours (EWH) Thermodynamic model for gas turbine plant Modelling of HRSG Performance parameters Results & discussion Energy and exergy analysis of ICCSVAC 230 xvii

19 Performance analysis with and without TES Economic analysis with and without TES Conclusions 238 Chapter-7: Overall conclusions and recommendations Further recommendations 245 References 247 Appendix-A 255 Appendix-B 259 Appendix-C 263 Appendix-D 269 About the author 271 xviii

20 Figure No LIST OF FIGURES Title Page No 1.1 Schematic diagram of solar based power generation methods Schematic of reference 500 MWe thermal power plant Schematic of integrated 500 MWe TPP with SAFWH in HPH Variation in DNI, Cosθ and DNI*Cosθ corresponding to the day of maximum solar radiation at Varanasi. (Latitude N & longitude E) 2.4 Annual reduction in coal, CO2 and ash for the solar aided 500 MWe sub critical TPP with and without TES option Variation of LCoE with discount rate for SAFWH in HPH-7 with and without TES Variation of LCoE with Plant capacity factor for SAFWH in HPH-7 with and without TES Variation of LCoE with Plant capacity factor for SAFWH in HPH-7 with and without TES Schematic of an integrated solar aided 500 MWe thermal power plant Physical structure of the 500 MWe sub critical coal fired thermal power plant Physical structure of the integrated solar aided 500 MWe thermal power plant with TES Productive structure of the 500 MWe sub critical coal fired thermal power plant Productive structure of the integrated solar aided 500 MWe thermal power plant with TES Simplified schematic view of 660 MWe coal fired supercritical thermal power plant Energetic efficiency of major power plant components at unit load of 660 MWe, 528 MWe and 396 MWe, under constant pressure operation Rate of exergy destruction of various power plant components at unit load of 660 MWe, 528 MWe and 396 MWe, under constant pressure 125 operation 4.4 Exergetic efficiency of all major power plant components at unit load of 660 MWe, 528 MWe and 396 MWe under constant pressure operation Energetic efficiency of all major power plant components at a unit load of 660 MWe, 528 MWe and 396 MWe under pure sliding pressure 132 operation 4.6 Rate of exergy destruction of various power plant components at a unit load of 660 MWe, 528 MWe and 396 MWe under pure sliding pressure operation 133 xix

21 4.7 Exergetic efficiency of all major power plant components at a unit load of 660 MWe, 528 MWe and 396 MWe under pure sliding pressure 133 operation 4.8 Comparison of rate of exergy destruction for Turbine at a unit load of 660 MWe, 528 MWe and 396 MWe between constant and pure sliding 134 pressure operation 4.9 Comparison of rate of exergy destruction for Boiler at a unit load of 660 MWe, 528 MWe and 396 MWe between constant and pure sliding 135 pressure operation 4.10 Comparison of rate of exergy destruction for the BFP at a unit load of 660 MWe, 528 MWe and 396 MWe between constant and pure sliding 136 pressure operation 4.11 Comparison of BFP power input at 660 MWe, 528 MWe and 396 MWe load conditions between constant and pure sliding pressure operation Integration of solar collector field and TES to a 660 MWe super critical TPP for feed water heating in HPH Variation in DNI, Cosθ and DNI*Cosθ corresponding to the day of maximum solar radiation at Raipur (latitude N and longitude E). (Source: ISHRAE weather files for 62 locations in India) 5.3 Annual reduction in coal, CO2 and ash for the solar aided 660 MWe super critical TPP with and without TES option Variation of LCoE with discount rate for SAFWH in HPH-7 with and without TES Variation of LCoE with plant capacity factor for SAFWH in HPH-7 with and without TES Variation of LCoE with fuel cost for SAFWH in HPH-7 with and without TES Schematic of 800 MWe super critical thermal power plant Integration of solar collector field and TES to an 800 MWe super critical TPP for feed water heating in HPH Variation in DNI, Cosθ and DNI*Cosθ corresponding to the day of maximum solar radiation at Belgaum (latitude N and longitude E) 5.10 Annual reduction in coal, CO2 and ash for the solar aided 800 MWe super critical TPP with and without TES option Variation of LCoE with discount rate for SAFWH in HPH-7 with and without TES Variation of LCoE with plant capacity factor for SAFWH in HPH-7 with and without TES Variation of LCoE with fuel cost for SAFWH in HPH-7 with and without TES Schematic of solar aided 660 MWe super critical coal fired thermal power plant with TES Physical structure of 660 MWe super critical coal fired thermal power plant Physical structure of solar aided 660 MWe super critical coal fired thermal power plant 175 xx

22 5.17 Productive structure of 660 MWe super critical coal fired thermal power plant Productive structure of solar aided 660 MWe super critical coal fired thermal power plant Schematic of reference combined cycle power plant (RCCPP) Schematic of proposed direct steam generation ISCCPP Energy and exergy efficiencies of CCPP with DSG Rate of exergy destruction of DSG ISCCPP components Schematic of integrated combined cycle with solar operated vapor absorption chiller (ICCSVAC) Energy and exergy efficiencies of ICCSVAC plant components Rate of exergy destruction of ICCSVAC plant components 232 xxi

23 Table No LIST OF TABLES Title Page No 1.1 Indian power sector scenario based on installed capacity FWH parameters, heat input, reference aperture area required &effective 44 working hours for LP and HPH s of reference power plant under study 2.2 Geometrical and optical parameters of the parabolic trough collector 46 (ET150) 2.3 Costs associated with economic analyses of reference power plants under 54 study Steps for calculating direct and indirect capital costs of reference power plants under study (Report on Engineering Economic Policy Assessment of Concentrated Solar Thermal Power Technologies for India sanctioned by Ministry of New & Renewable Energy, Govt. of India) 2.5 Flow stream data of the 500 MWe sub critical coal fired TPP at design load Performance parameters of 500 MWe reference power plant under study for different feed water heating options a) without SAFWH b) with SAFWH & without TES and c) with SAFWH & TES The direct and indirect capital costs for the 500 MWe sub critical TPP with 65 three different feed water heating options for SM=1 2.8 Economic analysis of solar aided 500 MWe sub critical TPP LCoE for SAFWH in the reference power plants under study with and 68 without TES for different solar multiples 2.10 Comparison of results of present work with work of Suresh et al 70 (2010) for SAFWH in fuel saving mode without TES 3.1 The fuel, product definitions for typical steam power plant components Thermoeconomic equations for plant units of 500 MWe sub-critical coal 90 fired thermal power plant 3.3 Flow stream data of integrated solar aided 500 MWe sub critical 93 plant at design load (SAFWH across the HP Heaters) 3.4 Energy and exergy analysis of solar aided 500 MWe TPP (SAFWH across 95 HP heaters) 3.5 Exergy and thermoeconomic analysis of 500 MWe sub critical coal fired 97 thermal power plant 3.6 Exergy and thermoeconomic analysis of solar aided 500 MWe sub critical 98 coal fired thermal power plant 4.1 Flow stream data of the reference plant at unit load of 660 MWe, MWe and 396 MWe under constant pressure operation. 4.2 Results of energetic analysis of 660 MWe power plant at unit load of MWe, 528 MWe and 396 MWe under constant pressure operation 4.3 Results of exergetic analysis of 660 MWe power plant at unit load of MWe, 528 MWe and 396 MWe under constant pressure operation Flow stream data of 660 MWe supercritical power plant at a unit load of 660 MWe, 528 MWe and 396 MWe under pure sliding pressure operation xxiii

24 4.5 Results of energetic analysis of reference plant at unit load of 660 MWe, MWe and 396 MWe under pure sliding pressure operation 4.6 Results of exergetic analysis of reference plant at unit load of 660 MWe, MWe and 396 MWe under pure sliding pressure operation FWH parameters, heat input, reference aperture area required &effective working hours for LP and HPH s of reference 660 MWe super critical power plant under study 5.2 Flow stream data of the 660 MWe super critical coal fired TPP at design 147 load. Performance parameters of 660 MWe reference power plant under study for different feed water heating options a) without SAFWH b) with SAFWH & without TES and c) with SAFWH & TES 5.4 The direct and indirect capital costs for the 660 MWe super critical TPP 151 with three different feed water heating options for SM= Economic analysis of solar aided 660 MWe super critical TPP LCoE for SAFWH in the reference power plants under study with and 154 without TES for different solar multiples FWH parameters, heat input, reference aperture area required &effective working hours for LP and HPH s of reference 800 MWe super critical power plant under study 5.8 Flow stream data of the 800 MWe super critical coal fired TPP at design 162 load Performance parameters of 800 MWe reference power plant under study for different feed water heating options a) without SAFWH b) with SAFWH & without TES and c) with SAFWH & TES 5.10 The direct and indirect capital costs for the 800 MWe super critical TPP 166 with three different feed water heating options for SM= Economic analysis of solar aided 800 MWe super critical TPP LCoE for SAFWH in the reference power plants under study with and 169 without TES for different solar multiples 5.13 Thermoeconomic equations for plant units of 660 MWe sub-critical coal 180 fired thermal power plant 5.14 Flow stream data of solar aided 660 MWe super critical plant Energy and exergy analysis of solar aided 660 MWe TPP (SAFWH across 185 HP heaters) 5.16 Exergy and thermoeconomic analysis of 660 MWe super critical coal fired 186 thermal power plant 5.17 Exergy and thermoeconomic analysis of solar aided 660 MWe super 187 critical coal fired thermal power plant 6.1 Design plant parameters of RCCPP Design point parameters of the solar field Geometrical and optical parameters of the collector system (Montes et 201 al, 2011) 6.4 Flow stream data of DSG ISCCPP Performance parameters of the reference CCP and DSG ISCCPP Economic analysis of reference CCPP and DSG ISCCPP Input parameters for the gas turbine plant model 221 xxiv

25 6.8 Geometrical and optical parameters of the parabolic trough collector Stream data of the ICCSVAC plant Performance parameters of the RCCPP, ICCSVAC and ICCSVAC TES Capital costs of the RCCPP, ICCSVAC and ICCSVAC TES Economic analyses of the RCCPP, ICCSAVAC and ICCSAVAC TES 236 xxv

26 Ar Reference aperture area (m 2 ) Aa Actual aperture area (m 2 ) LIST OF NOMENCLATURE b BD C FOM C F C L Do Di Dco Dci F r F FBi FN i FW i h Specific exergy (kj/kg) Rate of exergy destruction (MW) Fixed O&M cost per unit (USD/sec) Fuel cost per unit (USD/sec) Levelised fuel and O&M cost (USD/sec) Receiver outside diameter (m) Receiver inner diameter (m) Glass cover inner diameter (m) Glass cover outer diameter (m) Collector heat removal factor Collector efficiency factor Fuel exergy rate to i th plant equipment (MW) Fuel Negentropy rate to ith plant equipment (MW) Rate of work input to or rate of work output from the i th plant equipment (MW) Specific enthalpy (kj/kg) h w Outside convective heat transfer coefficient due to wind (W/m 2 K) h f Convective heat transfer coefficient for inside surface of receiver (W/m 2 K) Itotal Maximum solar radiation that can be captured over the year (kwhr/m 2 ) m Pi Mass flow rate (kg/sec) Product exergy rate from the i th plant equipment (MW) Q Cond Rate of heat rejection to circulating water in the condenser (MW) xxvii

27 Q K Q I Q u Rate of heat transfer (MW) Total solar power incident on the collector system (MW) Rate of useful thermal gain by the heat transfer fluid (MW) s Specific entropy (kj/kg. K) S gen T s T r Entropy generation (kj/k) Black body temperature of the Sun (K) Receiver temperature (K) T sky Sky temperature (K) U L V Z Loss coefficient Velocity (m/sec) Elevation (m) GREEK SYMBOLS θ Angle of Incidence η Efficiency/factor µ Dynamic viscosity ρ τ γ δ β ε ω Density Absorptivity Transmissivity Reflectivity Declination of the day Angle of tilt of parabolic trough Emissivity/Exergy destruction ratio Hour angle xxviii

28 ABBREVATIONS BOI BFP BFPT CEA CERC CCPP CSP CEP COND CI DEA DSH DCC DNI DC DP ECE EL EPC FWHE FWH FWH GT GW GSC GoI HRSG HTF HARP Boiler Boiler feed pump Boiler feed pump turbine Central Electricity Authority Central Electricity Regulatory Commission Combined cycle power plant Concentrating solar power Condensate extraction pump Condenser Cost index Deaerator De-Super heater of HPH-6 Direct capital cost Direct normal irradiance Drain cooler Drip pump Electronic controls and electricals End losses Engineering, procurement and construction Feed water heat exchanger Feed water heater Feed water heater Gas turbine Giga watt Gland steam condenser Government of India Heat recovery steam generator Heat transfer fluid Heater above reheat point xxix

29 HPH HPT IAM ISHRAE IDCC ISCCPP IF IPT LCoE LPH LPT MW MWe MNRE NREL NCR O&M PV PCF RPP RES SAFWH SAPG TWh TES TPP TDBFP TMY High pressure feed water heater High pressure turbine Incidence angle modifier Indian society of heating, refrigeration and air conditioning engineers Indirect capital cost Integrated solar combined cycle power plant Intercept factor Intermediate pressure turbine Levelised cost of electricity generation Low pressure feed water heaters Low pressure turbine Mega watt Megawatt electric Ministry of New and Renewable Energy Sources National Renewable Energy Laboratories Normal continuous rating Operation and maintenance Photo voltaic Plant capacity factor Reference power plant Renewable Energy Sources Solar aided feed water heating Solar aided power generation Tera watt hour Thermal energy storage Thermal power plant Turbo driven boiler feed water pump Typical meteorological year xxx