1. Commercialization of Solar cells

2. How it works  Cell  Modules  Panels  Arrays

3. Three Types of Silicon Solar cells  Monocrystalline  Multicrystalline  Amorphous

4. Monocrystalline These silicon cells are saw-cut from a single, cylindrical crystal of silicon. They are the most efficient of the three

5. Additional information  High efficiency, roughly 15%  Pure Silicon which means no impurities  Costs are much higher  More detailed required in manufacturing

6. Multicrystalline These are cut from an ingot of melted and recrystallized silicon.

7. Additional information  Less efficiency than Monocrystalline  Less expensive  Square cuts minimize wasted surface area

8. Amorphous silicon Rather than coming from a crystal structure, these cells are created from a thin layer of silicon atoms.

9. Additional information No structural uniformity like other silicon solar cells Requires less temperature to produce Often used for calculators and other small low energy devices Hydrogenation

10. Hydrogenation “But amorphous silicon can be deposited so that it contains a small amount of hydrogen, in a process called "hydrogenation." The result is that the hydrogen atoms combine chemically with many of the dangling bonds, essentially removing them and permitting electrons to move through the material.”

11. Czochralski process  Seed crystal dipped in molten crucible  Slowly pulled upward  Creates ingot as it slowly turns  Constant heat applied

12. Cutting Process  20% waste from cutting thin slices “kerf”  Wire saw with diamond

13. Coating  Anti-reflective coat  Electrical contact forms PV cells  Glass is used for the outside protective layer

14. John Geisz and Mark Wanlass  40.8 solar cell efficiency  Highest ever recorded  Under 326 suns  Gallium indium phosphide

15. How to make a PV at home  Cut out a copper piece equal to electric burner size  Leave it on for roughly 1.5 hours until it oxidizes (complete black)

16.  Let it cool after it has turned black  As it cools it will shrink (different rates of shrinking)  Flake off the rest with your hands

17. Complete the Circuit  After majority of the black flakes are off, cut another copper sheet equal in size  Connect clips to each piece dipped in water with sunlight

18. Too much for too little  Only produces.25V at 25 microamps  Not efficient  Requires acres to actually make use  80,000 square meters to light 100 lightbulbs

19. Videos  http://www.youtube.com/watch?v=qYeynLy6 pj8 http://www.youtube.com/watch?v=qYeynLy6 pj8 http://www.youtube.com/watch?v=qYeynLy6 pj8  http://www.huffingtonpost.com/2009/05/22/s olar-plane-crosses-alps_n_206835.html

20. Spacecrafts  US satellite Vanguard 1, launched in March 1958 with solar cells made by Hoffman Electronics  This was a crucial development which stimulated funding from several governments into research for improved solar cells

22. U.S Solar Cells  30 megawatt  Being built for Austin, Tx  Nearby Weberville  300 Acres

23. Looking at the Future  Sahara Desert  Worlds largest solar array .03% area is enough to power all of Europe

24. Army

25.  12 acres covering former landfill in Colorado  2 megawatt  Largest array in army

26. Resources  http://www1.eere.energy.gov/solar/silicon.html http://www1.eere.energy.gov/solar/silicon.html  http://www.beyondzeroemissions.org/2008/08/26/Dr- Mark-Wanlass-discusses-award-winning-inverted- metamorphic-multi-junction-photovoltaic-cell http://www.beyondzeroemissions.org/2008/08/26/Dr- Mark-Wanlass-discusses-award-winning-inverted- metamorphic-multi-junction-photovoltaic-cell http://www.beyondzeroemissions.org/2008/08/26/Dr- Mark-Wanlass-discusses-award-winning-inverted- metamorphic-multi-junction-photovoltaic-cell  http://scitoys.com/scitoys/scitoys/echem/echem2.html http://scitoys.com/scitoys/scitoys/echem/echem2.html  http://dvice.com/archives/2009/06/worlds-largest-4.php http://dvice.com/archives/2009/06/worlds-largest-4.php  http://www.inhabitat.com/2009/06/03/us-largest-solar- power-facility-approved-in-austin/ http://www.inhabitat.com/2009/06/03/us-largest-solar- power-facility-approved-in-austin/ http://www.inhabitat.com/2009/06/03/us-largest-solar- power-facility-approved-in-austin/  http://ecoworldly.com/2008/03/05/worlds-7-biggest-solar- energy-plants/