hydrogen production from water using solar cells powered nafion ...

LIST OF FIGURES
Figure 2.1. Various sources for electroylsis .....................................................................43
Figure 2.2. Schematic represantation of a PEM electrolysis cell .....................................14
Figure 2.3. Molecular Formula of Nafion.........................................................................19
Figure 3.1. 2D Schematic representation of an electrolysis cell.......................................32
Figure 3.2. Anode side of the electrolysis cell..................................................................44
Figure 3.3. Cathode side of the electrolysis cell ...............................................................33
Figure 3.4. Parts of an electrolysis cell.............................................................................34
Figure 3.5. Single cell electrolysis setup ..........................................................................36
Figure 3.6. 2D schematic representation of a PEM electrolysis stack..............................37
Figure 3.7. a) Front Side of the bipolar plate........................................................................45
b) Rear Side of the bipolar plate .........................................................................37
Figure 3.8. Two cell electrolysis stack .............................................................................38
Figure 3.9. Multi Cell Electrolysis Stack Test Setup........................................................40
Figure 3.10. Solar power driven electrolyzer stack setup...................................................47
Figure 4.1. X” type flow field design ...............................................................................43
Figure 4.2. Pin Type Flow Field.......................................................................................44
Figure 4.3. Empty Flow Field...........................................................................................45
Figure 4.4. Empty Flow field with crosswise ducts..........................................................44
Figure 4.5. Results of Electrolysis Trials..........................................................................48
Figure 4.6. (a-d) Temperature Effect on Electrolysis .......................................................50
Figure 4.7. Voltage of the cells at 500mAmp/cm 2 ...........................................................51
Figure 4.8. Minimum and Thermoneutral Electrolysis Voltage.......................................51
Figure 4.9. (a)-(c) Excess Water Flow Effect on Electrolysis ..........................................53
Figure 4.10. Voltage of the cells at 500mAmp/cm 2 ...........................................................54
Figure 4.11. Calculated and Measured Oxygen and Hydrogen Flows ...............................55
Figure 4.12. Current Voltage Curves of the Cells of an Electrolyzer Stack.......................56
Figure 4.13. Hydrogen Production vs. Current Density .....................................................57
Figure 4.14. Current-Voltage Curves of a PV Module.......................................................58
Figure 4.15. Solar Radiance Data on 18.12.2006 ...............................................................60
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