Combined Electricity and Water Production Based on Solar Energy Von der Fakultät für Energie-, Verfahrens- und Biotechnik der Universität Stuttgart zur Erlangung der Würde eines Doktor-Ingenieurs (Dr.-Ing.) genehmigte Abhandlung Vorgelegt von Dipl.-Ing. Massimo Moser aus Mezzolombardo (Italien) Hauptberichter: Prof. Dr. rer. nat. habil. André Thess Mitberichter: Prof. Dr. Giorgio Micale Tag der mündlichen Prüfung: 29.01.2015 Institut für Energiespeicherung der Universität Stuttgart 2014 II Content 1 Introduction ................................................................................................ 1 1.1 Motivation ...............................................................................................................1 1.2 Structure of the Work ...............................................................................................3 2 Modeling Approach ..................................................................................... 6 2.1 Review of Existing Simulation Tools ..........................................................................6 2.2 The INSEL Software ..................................................................................................9 2.2.1 INSEL Blocks ......................................................................................................9 2.2.2 INSEL Systems .................................................................................................10 2.3 Excel-Tool for Economic Analysis ............................................................................11 3 Desalination Models .................................................................................. 13 3.1 Multi-Effect Distillation (MED) ................................................................................15 3.1.1 Water Pretreatment ........................................................................................15 3.1.2 Process Description .........................................................................................16 3.1.3 MED Model .....................................................................................................18 3.1.4 Drinking Water Post-Treatment.......................................................................27 3.1.5 Brine Discharge ...............................................................................................28 3.1.6 MED INSEL Block .............................................................................................29 3.2 Reverse Osmosis (RO) .............................................................................................30 3.2.1 Water Pretreatment ........................................................................................30 3.2.2 Process Description .........................................................................................32 3.2.3 RO Model ........................................................................................................38 3.2.4 Drinking Water Post-Treatment.......................................................................43 3.2.5 Brine Discharge ...............................................................................................44 3.2.6 RO INSEL Block ................................................................................................45 4 Concentrating Solar Power (CSP) Models .................................................. 46 4.1 Sun Position Calculation .........................................................................................48 4.2 Parabolic Trough ....................................................................................................50 4.2.1 Geometrical Efficiency .....................................................................................51 4.2.2 Receiver Model ...............................................................................................53 4.2.3 Piping Model and Auxiliary Power Consumption .............................................58 4.2.4 Transient Model ..............................................................................................60 4.2.5 Molten Salt Collector Model ............................................................................61 4.2.6 Direct Steam Generation .................................................................................62 4.3 Linear Fresnel .........................................................................................................65 4.3.1 Geometrical Efficiency .....................................................................................66 4.3.2 Receiver Model ...............................................................................................68 III 4.3.3 Piping and Auxiliary Power Consumption ........................................................68 4.4 Central Receiver .....................................................................................................68 4.4.1 Geometrical Efficiency .....................................................................................69 4.4.2 Receiver Model ...............................................................................................72 4.4.3 Piping and Auxiliary Power Consumption ........................................................74 4.5 Molten Salt Tanks Storage ......................................................................................74 4.6 Power Block............................................................................................................78 4.6.1 Steam Turbine .................................................................................................78 4.6.2 Cooling System ................................................................................................84 4.7 CSP INSEL Blocks .....................................................................................................86 5 Photovoltaic Model ................................................................................... 87 5.1 PV Model ................................................................................................................88 5.2 INSEL PV Blocks ......................................................................................................90 6 Wind Power Model .................................................................................... 91 6.1 Wind Model ...........................................................................................................91 6.2 INSEL Wind Blocks ..................................................................................................94 7 Economic Analysis ..................................................................................... 95 7.1 Levelized Electricity Cost (LEC) ................................................................................95 7.2 Levelized Water Cost (LWC) ....................................................................................98 7.3 System Supply Cost .............................................................................................. 101 8 Case Studies ............................................................................................ 102 8.1 Model Inputs and Main Assumptions ................................................................... 103 8.2 Renewable Electricity Generation ......................................................................... 108 8.2.1 CSP ................................................................................................................ 108 8.2.2 PV.................................................................................................................. 123 8.2.3 Wind Power .................................................................................................. 127 8.3 Seawater Desalination .......................................................................................... 128 8.3.1 MED .............................................................................................................. 128 8.3.2 MED-TVC ....................................................................................................... 137 8.3.3 RO ................................................................................................................. 141 8.4 Combined Systems for Water and Power Supply .................................................. 146 8.4.1 Power Supply Mix with SWRO ....................................................................... 147 8.4.2 Power Supply Mix with CSP-MED .................................................................. 152 8.4.3 Final Assessment ........................................................................................... 154 9 Conclusions and Outlook ......................................................................... 157 IV 10 Annex ...................................................................................................... 160 10.1 Desalination ......................................................................................................... 160 10.1.1 Preliminary Comparison of Desalination Technologies .................................. 160 10.1.2 Water Intake and Pre-Treatment ................................................................... 163 10.1.3 Desalination Processes .................................................................................. 166 10.1.4 Brine Discharge ............................................................................................. 167 10.1.5 Desalination Markets ...................................................................................