Great thanks to Dr.Gabler for this informative presentation (data 2010 updated) www.devi-renewable.com

1. Hansjörg Gabler Zentrum für Sonnenenergie- und Wasserstoff-Forschung (ZSW) Baden-Württemberg, Stuttgart, Germany DAAD Summer School 'Solar Shift' ZEE – Zentrum für Erneuerbare Energien Albert-Ludwigs-Universität Freiburg, Germany Freiburg, 31 May 2011 Electricity from the Sun -an Introduction

2. PV-generator on farm-building roofs (Peiting-Hausen, 77 kW P , 2003)‏ Source: Sputnik Engineering AG / Photon 10/2003

3. Photovoltaics : direct conversion of sunshine into electricity! New installations ¹ in year 2010, world: 15.4 GW Cumulative installation until end of 2010: 37.4 GW Electricity produced ² from PV in 2010, world: 44 000 GWh Net electricity generation Germany in 2009: 617 000 GWh Net electricity generation ³ Bangladesh in 2008: 26 000 GWh (1): Rated capacity, Photon 3/2011, p. 36, average from 10 independent estimates (2): very rough estimation: 'production' = 1200 kWh/a*kW (3): 'country Report', Hirak Al-Hammad PPRE, 2009 Oldenburg University, Oldenburg

6. Solar cells are electrically connected “in series” to achieve higher voltages Source: Photon Special 2004

7. Typical Structure: • Glass • Transparent lamination foil (Ethylen Vinyl Acetat: EVA) • Solar cells, electrically connected • back side protection (Teflon foil or glass) Packaging of solar cells into a solar “module” protects against destructive environment Source: Photon Special 2004

8. Module (Solar Panel): Siemens SM55 monocrystalline Silicon Source: Siemens Solar GmbH, Germany

9. PV-generator on farm-building roofs (Peiting-Hausen, 77 kW P , 2003)‏ Source: Sputnik Engineering AG / Photon 10/2003

11. Cost breakdown for a solar system based on Si-wafer PV cells, status 2006 Dates from J. Conkling, M. Rogol, The true cost of solar power, (Solarverlag, April 2007)‏

12. Solar cell production 1999 to 2010 Quelle: PHOTON International 2011

13. Shares per region for 2010 (2009) Quelle: PHOTON International 2011

14. PV industry turnover PV systems installed in 2010: 15.4 GW price of system installed: 3.0 €/W -> turnover solar industry: 45 billion € annual solar industry growth rates ˃ 50% over last 10 years turnover semiconductor industry (components): 200 billion € annual long term growth rate 10%

15. Price of PV-Systems and PV-Electric Energy Expected development: SRA EU PV Platform (2007)‏ Source: A strategic research agenda for Photovoltaic Solar Energy Technology Prepared by EU PV Technology Platform, Final Version June 2007 Assumptions: System yield at 1700 kWh/m²/yr: 1275 kWh/kWp/yr, O&M = 1 % of system price/yr, discount rate 4 %, depreciation time 25 years 0.03 0.06 (competitive with wholesale electricity)‏ 0.15 (competitive with retail electricity)‏ 0.30 >2 Typical electricity generation costs, Southern Europe (2007 €/kWh)‏ 0.5 1 2.5 5 >30 Typical turn-key system price (2007 €/Wp, excl. VAT)‏ Long term potential 2030 2015 Today 1980

17. Quelle: Photon 1/2001 International Space Station ISS, 1. Ausbaustufe: 62 kW (+ 16 kW)‏ Si-Zellen,  = 14,5 %

18. Suohourima township in November 2005, Qinghai Province Rural Electrification: China

19. System operator in front of 40 kW PV Generator, Suohourima Rural Electrification: China

20. Farmer with Solar Home Systems, June 2007, Kesheng, Qinghai Province

21. Grameen Shakti , Bangladesh SHS / PV: 40 – 120 Wp price: 430 US$ for 50 W-system microcredit: downpayment: e.g. 25%, loan@4%, payback over 2 years 60 000 SHS per annum (2008) 110 000 SHS (2009) source: The Ashden Awards for Sustainable Energy (www.ashdenawards.org) and: www.gshakti.org Bangladesh, end of 2009: SHS (total): 438 000 Installations in 2009:168 000 source: Shahriar Ahmed Chowdhury United International University Dhaka, Bangladesh, private communication.

23. Navarra, Spain. Total power 1.2 MW, 280 tracker units with „BP-Saturn“ modules, 120 trackers with modules from other suppliers. Tracking along azimuth axis, module tilt 45°, commissioning 2003. Source: EU PV Project Synopsis, 2003 Grid Connected PV Power:

24. PV-generator on the roof of a family house (Sperberslohe-Wendelstein, 4.0 kW P , 2001)‏ Source: Photon 3/2005

30. Notwithstanding severe price decreases, PV electricity is not yet competitive to traditional forms of electricity (coal, large hydro ...)‏ to reach market competitiveness for bulk electricity, Photovoltaics still has a long way to go! 'We've come far, and we have far to go', (Paula Mints, Navigant Consulting, Palo Alto, Calif.) And there are good reasons to go ahead ...

31. Technologies of todays Photovoltaic cells: Form of semiconductor: Crystalline wafers (slices) or: thin films on substrates Material : Crystalline silicon or: other semiconductors

33. CIS Thin Film PV cell SEM picture of cross section of PV cell Picture: ZSW TCO/ZnO Absorber/CIGS Back contact/Mo Substrate/glass Buffer/CdS

34. Technology options for major cost reductions:  Progress and innovation in crystalline (Wafer) Si-technology: increase efficiency, reduce material costs, innovate cell and module design increase productivity of investment  Progress and innovation in PV Thin Film technologies  Concentrating Photovoltaics (CPV)‏  Emerging and novel PV-technologies

35. European Union: “Strategic Research Agenda for Photovoltaic Solar Energy Technology” (June 2007)‏ Status Target 2015 Turn key system price 5 €/Wp 2.5 €/Wp Cost of PV-module 2.0-2.5 €/Wp 1.0 €/Wp (Poly-) Silicon consumption 10 g/W 5 g/W (Wafer thickness reduced, Kerf losses reduced, high yield handling etc.)‏ Efficiency of module (Poly-Si) 13 % > 17 % Specific manufacturing plant investment (long term target) 1 €/Wp < 0.5 €/Wp Module manufacturing: roll-to-roll / automatic module assembly Component standardisation to reduce installation and maintenance costs

36. Bild poly si

39. Technology options for major cost reductions:  Progress and innovation in crystalline (Wafer) Si-technology  Progress and innovation in PV Thin Film technologies. increase efficiencies innovative production technologies  Concentrating Photovoltaics (CPV)‏  Emerging and novel PV-technologies

40. Why Thin-Film Photovoltaics? “ Thin” => thin active layers on a cheap substrate, => low material costs ( material needed for 1 kW PV: CIS = 0.2 kg / X-Si = 10 kg)‏ “ Thin” => little energy needed for production Commercial technologies from the “flat panel display” and the making of architectural glass may be adapted. ==>Thin Film PV has high cost reduction potential!

41. Deposition equipment for “low emission glass” Picture: Von Ardenne Anlagentechnik Producing >10 km² of complex thin layers on glass per year (10 km² of PV-module have a nominal capacity of > 1 GW)‏

42. Thin Film PV Production Line, FirstSolar in Ohio Line capacity: 25 MW/yr Foto: FirstSolar

43. Vertical Integration in Production POLY Si Si wafer Si cell PVmodule thin-film factory glass, raw materials modules Crystalline silicon Thin-film technology all production steps in one line

44. The three thin film technologies in production or under construction today, a-Si, CdTe, CIS 2007 14 % 9 - 12 % - CIS process is complex CIS 12 % 8 - 10 % - production, CdTe 10-11 % 6 - 7 % - production - a - Si / µ c - Si 2012 14 % 9 - - 12 % - - CdTe: fast process 6 - 7 % - industrial mass - in the market - µ Module efficiency - State of Technology 450 MW 1450 MW 1350 MW industrial mass duction on the way, turn-key solutions industrial mass pro- Module efficiency Module production 2010 Source: estimate ZSW, cell/module production 2010: photon 4/2011

45. Development of Thin-Film Solar Cells

46. The PV park Buttenwiesen came online in Sept. 2004. With 1 MW installed power using amorphous silicon modules from Mitsubishi Heavy Industries, it was at it’s time the world’s largest ground-mounted PV generator with Thin-Film modules. Source: Phönix SonnenStrom AG

48. Flexible and light weight Thin Film Modules For the power market: Low cost PV-modules through “roll to roll” production Picture: Solar Integrated, www.solarintegrated.com Portable power source (mobile communications), integration into flexible structures (tent roofs, air ships)‏ IPC Solar, www.IPC-Solar.com

50. - - Quelle: PHOTON Europe GmbH 2011

51. Technology options for major cost reductions:  Progress and innovation in crystalline (Wafer) Si-technology  Progress and innovation in PV Thin Film technologies  Concentrating Photovoltaics (CPV)‏  Emerging and novel PV-technologies

52. Why Concentration Technologies? The basic idea: Use cheap optics for collection of the sunlight and reduce the expensive semiconductor material Reduce cost of PV-generated kWh solar radiation lens F 0 solar cell F c heat transport

54. Use high-efficient Cells: III-V Multi-junction Cells! Si GaInP GaInAs Ge

57. b Cool earth Solar www.daido.co.jp/english

58. Cost break down for a solar system based on Si-wafer PV cells, status 2006 Dates from J. Conkling, M. Rogol, The true cost of solar power, (Solarverlag, April 2007)‏

59. Technology options for major cost reductions:  Progress and innovation in crystalline (Wafer) Si-technology  Progress and innovation in PV Thin Film technologies  Concentrating Photovoltaics (CPV)‏  Emerging and novel PV-technologies (organic solar cells, 'up/down conversion', Thermo-Photovoltaics, ................................... )‏

60. Roads to Cost Reduction (the medium and long term perspective): • Novel Photovoltaic Technologies Target 2020: Make PV cells with efficiency > 30 % by using larger parts of the sun’s spectrum than single layer cells

61. Organic Solar cells (Polymer cells) principle: Replace the (anorganic) semiconductor silicon resp. CIS, CdTe etc. by a semiconducting polymer. These polymers are developed for LEDs (OLED). Very large research programmes in Europe and in the US focus on organic solar cells. Private companies are engaged (Konarca, …) in the field Best cell efficiencies: 7.1%, (EUPVSEC Valencia, 2010)

62. Organic solar module on polymer foil, prototype photo: Fraunhofer press (www.young-germany.de)‏

63. Source: http://www.energystocksblog.com/2008/06/21/photovoltaic-summit-2008-dr-pv-mr-pv-and-the-terawatt-dilemma/

64. Concluding remarks: All solar panels in power applications must operate for more than 20 years , without larger power losses! A number of 'classic' wafer silicon panels has successfully operated over that time. Each new technology has again to prove it's stability and durability, risk has to be compensated with price reductions. The disscussion on the future of Photovoltaics is often focussed on solar cell development, 'Pane l' technology and 'System' technology, which both have a high share of the total costs, are of equally high importance..

66. Thank you for your attention! Thank you for your attention!