1. CHAPTER TWO THE PHOTOVOLTAIC EFFECT 2e A G.I. Module Energie Solaire Copyright, 2006 © Ahmed S. Bouazzi المدرسة الوطنية للمهندسين بتونس

2. The Photovoltaic Effect (1) The p-n Junction

3. E c E v E f Electrons current Holes current The photocurrent under illumination PHOTOVOLTAIC EFFFECT (2)

4. The Photovoltaic Effect (3) The photovoltage under illumination

5. I-V Characteristic of a p-n junction J (A/cm 2 ) V (mV) -J-J L Illumination Dark

6. Voltage (V) V co J sc Current (A/cm 2 ) (J,V) I-V Characteristic of a PV Generator The slope is 1/R

7. Hole density in the n side: Electron density in the p side: Minority Carrier Concentration = 0

8. G ( x, ) =   ( )  ( ) exp { -  ( ) x }   ( ): flux of the incident light The Generation Function  wavelength of the light  ( ):absorption coefficient

9. Holes current (n side): Electrons current (p side): Photocurrent

10. p n d d+w l x h 0 n= 0 p= 0 Boundary Conditions

11. Holes current (n side): Electrons current (p side): Pseudo-neutral Regions Photocurrent Derivation

12. J w = q  o { exp (-  d) - exp [-  (d+w)]} = q  o exp (-  d)[1 - exp (-  w)] Depletion Region Photocurrent

13. Absorption Coefficient

14. n-side Photocurrent

15. p-side Photocurrent

16. For a given wavelength  Quantum Response

17. The Effect of the Surface Recombination Velocity

18. The Effect of the Junction Depth

19. The Solar Spectrum

20. The total photocurrent: The Total Solar Current

21. I-V Characteristic of the PV Generator

22. Maximum Voltage

23. Maximum Photocurrent

24. Open Circuit Voltage

25. The Fill Factor

26. The Efficiency

27. The Output Power

28. The Ideal Equivalent Circuit

29. The Real Equivalent Circuit

30. The Real Circuit Equation

31. The Fill Factor

32. The Series Resistance Effect

33. The Shunt Resistance Effect

34. The Cell Temperature Effect