I made this little study for the course Corporate Environmental Protection, I calculated the electricity produced and the energetic payback time for two identical installations: one in Dresden and one in Tunis. 10 minutes were too little, the subject is interesting and can be further developed.

1. Assessment of the environmental
friendliness of Photovoltaic cells:
Energetic aspect
Credits: http://www.eets.co.uk.
Amin Zayani 2806043 ERM WS 2009/10 14.01.2010
Corporate Environmental Protection
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2. Table of contents:
1. Basics of PV technology
2. Fields of use
3. Industry overview
4. Energy payback periods
4.1.!Comparison based on geographic location: Case study
4.2. Use in automotive industry: Case study
4.3. Use in consumer electronics
5. Conclusion
6. References
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3. 1. Basics of PV technology
Credits:http://www.sunnywinenergy.com
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4. 2. Fields of use
•Residential installation
•Commercial plants
•Off-grid systems
•Consumer goods
Credits:http://www.ardenhamenergy.co.uk http://technology4life.wordpress.com http://www.iteco.ch http://www.homesolarinfo.com
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5. 3. Industry overview
Credits:Global Market Outlook for Photovoltaics until 2013 EPIA . April 2009
Historical development of Global cumulative PV power installed per region
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6. 4. Energy payback periods
Credits: Life Cycle Assessment of Photovoltaics: Update of ecoinvent data. Energy research Centre of the Netherlands, Unit Solar Energy
Swiss PV installations: Payback time. 2008.
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7. #
Credits: Life Cycle Assessment of Photovoltaics: Update of ecoinvent data. Energy research Centre of the Netherlands, Unit Solar Energy
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8. 4. Energy payback periods
Credits: Energy payback times of PV modules and systems. Mariska de Wild-Scholten. November 2009.
Energy Payback time for PV cells 2009
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9. 4.1.!Comparison based on geographic location: Case study
Germany: Dresden
Yearly global irradiation: 1130 [kWh/m2]
Tunisia: Tunis
Yearly global irradiation: 1818 [kWh/m2]
Meteotest; database Meteonorm!(www.meteonorm.com)
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10. IKEA Dresden:
Parking area = 38588m2
Credits: http://cam.sit-livecam.de/Ikea. July 2009.
Carrefour Tunis:
Parking area = 38530m2
Credits: Bilel Gaaliche. April 2009.
Credits: Bilel Gaaliche. April 2009. 10

11. Technology chosen: CdTe
• First Solar FS Series 2 PV Module (FS - 277)
• Area: 0.72m2
• Rated power output: 58.1Wp
• Warranty: power output warranty of 90%
of the nominal output power rating during
the first10 years and 80% during 25 years.
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• Cumulative1B05C0123435672/859
energy input (industry
standard): 12236 MJ/kWp
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• CdTe: By product from Zinc
1B05C0123435672/G@refining. Not
classified as hazardous.
Credits: First Solar.
.../0123435672/859
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12. Results:
Number of
Total parking PV covered Yearly
Site area area
panels Peak capacity
production
installed
Dresden 38588 m! 25000 m! 34722 2 MWp 1716 MWh
Tunis 38530 m! 25000 m! 34722 2 MWp 2675MWh
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13. Energy payback time:
Total Yearly Efficiency in Avoided
Energy
Site Cumulative generated electricity primary
payback time
energy input electricity supply energy
Dresden 685.7MWh 1716 MWh 3.16KWh 5435 MWh 1.26 years
Tunis 685.7MWh 2675MWh 3.16KWh 8469MWh 0.8 years
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14. Energy payback time:
1
2,700,000
1
2,025,000
1,350,000 1
675,000 0
Dresden Dresden
0
Tunis 0
Tunis
Yearly produced electricity [KWh] Payback time [years]
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15. 4.2. Use in automotive industry
•Bollore/Pininfarina Blue car:
330"/ month.
•Fisker Karma.
Credits: Blue Car.
Credits: Fisker Automotive.
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16. 4.2. Use in automotive industry: Case study
•Manufacturer: Toyota
•Modifier: Solar Electric
Vehicles
•PV module : 215Wp
•The car uses 95-110 Wh/Km
(in full-electric mode)
•Drives 8 to 13 km on one day
solar charge (California
conditions)
Credits: http://www.solarelectricalvehicles.com
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17. Manufacturer Data:
Useful life: 160,000 Km
4.28L/100 Km 5.23L/ 100Km
Assumptions:
17 to 29 % savings
Total consumption: 6882 L 8411 L
Savings 1185 to 2010 L 1446 to 2453 L
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18. 4.3. Use in consumer electronics
•100% renewable energy
supply.
•Increased independence
from electricity plugs =
autonomy.
•Avoids a lot of toxic
disposable batteries from
going to waste.
•Adds a non-hazardous
component to the devices.
Credits: http://www.crunchgear.com http://education.ti.com http://www.china-solar.com/
http://www.coolest-gadgets.com/ http://www.casio.co.uk http://www.made-in-china.com
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19. 5. Conclusion
•PV cells energetic payback time ranges between < 1 year
and 5 years depending on the location and the
technology.
•Manufacturers are decreasing material and energy used
for economical reasons.
•PV cells supply green electricity to the grid and off the
grid.
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20. 6. References
• ENVIRONMENTAL IMPACTS OF PV ELECTRICITY GENERATION - A CRITICAL COMPARISON OF ENERGY SUPPLY
OPTIONS, Alsema, De wild Fthenakis. 2006
• Energy payback times of PV modules and systems Mariska de Wild-Scholten. 2009.
• Environmental Assessment and Metrics for Solar: Case Study of SolFocus Solar Concentrator Systems
• Life Cycle Assessment of Photovoltaics: Update of ecoinvent data. Energy research Centre of the Netherlands, Unit Solar
Energy
• European Commission, Joint Research Centre Institute for Energy, Renewable Energy Unit
http://re.jrc.ec.europa.eu/pvgis/index.htm
• Global Market Outlook for Photovoltaics until 2013 EPIA . April 2009
• http://www.solarelectricalvehicles.com/articles/prius-white-paper.shtml <last access: 14.01.2010>
• www.Firstsolar.com <last access: 13.01.2010>
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