Thermo-Economic Analysis of a Solar Thermal Power Plant with a Central Tower Receiver for Direct Steam Generation Ranjit Desai KTH Royal Institute of Technology April-September 2013. ([email protected]) EMN, École des Mines de Nantes. KTH, Royal Institute of Technology. BME, Budapest University QUB, Queen’s University, Belfast UPM, Universidad Politécnica de Madrid Ranjit Desai Index Note Master’s Thesis i Ranjit Desai Index Note Master’s Thesis Supervised by Institute Tutor Academic Tutor Rafael E. Guédez Dr. Claire Gerente KTH Royal Institute of Technology Ecole des Mines de Nantes Concentrating Solar Power Group GEPEA UMR CNRS 6144, Department of Energy Technology/ Heat and Power Division 4 Rue Alfred Kastler, BP 20722. Brinellvägen 68, SE-100 44. 44307, Nantes Cedex 03, Stockholm, SWEDEN. Nantes, FRANCE. ii Ranjit Desai Index Note Master’s Thesis INDEX NOTE Report Title: Thermo-Economic Analysis of a Solar Thermal Power Plant with a Central Tower Receiver for Direct Steam Generation Placement Title: Research Internship Author: Ranjit Desai Institute: KTH Royal Institute of Technology Address: KTH Royal Institute of Technology Department of Energy Technology/ Heat and Power Division, Brinellvägen 68, SE-100 44. Stockholm, SWEDEN. Institute Tutor: Rafael E. Guédez Role: Research Assistant Academic Tutor: Dr. Claire Gerente Summary: Amongst the different Concentrating Solar Power (CSP) technologies, central tower power plants with direct steam generation (DSG) emerge as one of the most promising options. These plants have the benefit of working with a single heat transfer fluid (HTF), allowing them to reach higher temperatures than conventional parabolic trough CSP plants; this increases the efficiency of the power plant. The goal of the study is to evaluate the thermodynamic and economic performance of one of these plants by establishing a dynamic simulation model and coupling it with in-house cost functions. In order to do so, the TRNSYS simulation studio is used together with MATLAB for post processing calculations. Furthermore, a valuable expected outcome of the work is the development, verification and validation of new DSG component models in TRNSYS for performance estimation; such as a central tower receiver model and steam accumulators for storage. Lastly, thermo-economic optimization of the power plant performance and costs will be addressed using a multi-objective optimization tool to determine the trade-offs between conflicting objectives, such as water depletion and the levelized electricity cost (LEC). iii Ranjit Desai Index Note Master’s Thesis Contents Index Note .................................................................................................................................................... iii List of Tables .................................................................................................................................................. v List of Figures ................................................................................................................................................. v Nomenclature .............................................................................................................................................. vi ACRONYMS ..................................................................................................................................................... VI GREEK LETTERS .............................................................................................................................................. VII SUBSCRIPTS .................................................................................................................................................... VII 1 Introduction ............................................................................................................................................. 1 2 Objectives ................................................................................................................................................. 2 3 Theoretical Framework ............................................................................................................................ 3 3.1 LINE-FOCUSING CSP .................................................................................................................................. 3 3.1.1 PARABOLIC TROUGH CONCENTRATOR ........................................................................................................................ 3 3.1.2 LINEAR FRESNEL REFLECTOR ....................................................................................................................................... 3 3.2 POINT-FOCUSING CSPS ............................................................................................................................. 4 3.2.1 DISH STIRLING ........................................................................................................................................................... 4 3.2.2 SOLAR CENTRAL TOWER SYSTEM ............................................................................................................................... 5 4 Methodology ........................................................................................................................................... 6 4.1 POWER BLOCK ......................................................................................................................................... 6 4.2 THERMODYNAMIC MODEL OF POWER BLOCK ............................................................................................... 7 4.2.1 STODOLA EXPANSION MODEL ................................................................................................................................... 7 4.2.2 THE NTU-EFFECTIVENESS METHOD .......................................................................................................................... 8 4.2.3 FEED WATER PUMP .................................................................................................................................................... 9 4.2.4 INDIRECT AIR-COOLED CONDENSER .......................................................................................................................... 9 4.3 RECEIVER MODELLING .............................................................................................................................. 9 4.3.1 LITERATURE REVIEW ................................................................................................................................................. 10 4.3.2 THE MODEL .............................................................................................................................................................. 10 4.4 CRITICALITY OF THE DIMENSIONS .............................................................................................................. 13 4.4.1 CRITICAL METAL TEMPERATURE ............................................................................................................................... 13 4.4.2 PRESSURE DROP ........................................................................................................................................................ 14 5 Analysis................................................................................................................................................... 16 5.1 OPTIMIZATION BASED ON DIMENSIONS ...................................................................................................... 16 5.2 ECONOMIC ANALYSIS ............................................................................................................................... 17 5.3 SELECTED DESIGN.................................................................................................................................... 18 6 Future work ............................................................................................................................................ 19 6.1 FORTRAN PROGRAMMING ..................................................................................................................... 19 7 Conclusion .............................................................................................................................................. 20 8 References .............................................................................................................................................. 21 iv Ranjit Desai Index Note Master’s Thesis Appendix ...................................................................................................................................................... 24 APPENDIX A: TUBE SELECTION HANDBOOK FOR AISI 316L .................................................................................. 24 APPENDIX B: OPTIMIZED STATES FROM POWER BLOCK ....................................................................................... 25 APPENDIX C: GNATT CHART.............................................................................................................................. 26 APPENDIX D: FORTRAN PROGRAM WINDOW IN MVS 2008 .................................................................................. 27 APPENDIX E: ANALYSIS GRAPHS FOR SH SECTION AND RH SECTION ...................................................................... 28 SH SECTION 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