1. Paolo Enrico de Falco 472839 1

2.  Solar panel electricity cost about 25 cents kilowatt-hour ( the average cost of electricity in the USA is 10 cents per kilowatt- hour ). Efficiency Costs  Solar panels can normally convert less than 15% of the sunlight that fall on them into energy. 2 3

4. Some companies such as  Day4  Suniva are improving, with their projects, the efficiency of solar panels and decreasing their costs. 4 5 6

5. What are Day4’s innovations? Implementation of a new electrode New design of the solar panel What are Suniva’s innovations? Reduction of the silicon layer thickness of 50% thanks to a reflective layer Utilization of a screen printing technique to incorporate materials to solar cells

6.  Replacement of thick silver bus bars with thin rows of coated copper wires  Implementation of a thinner silicon top layer Higher electrical conductivity with less power loss Increased silicon area for absorbing light More light converted into electricity = higher solar cells power output 7 Day4 solar panel Traditional solar panel Thick bus bars No thick bus bars

7.  The solar electricity produced with Day4’s solar panel will be 25% cheaper than the price of electricity of traditional solar panels. The average cost of electricity in USA is still smaller than the cheaper Day4’s panel.  The new designed panel will achieve an efficiency around 17% up from 14% mantaining the same price. 8

8. 9 Reflective layer implemented to the cells Longer persistence of the light photons into the silicon More light is absorbed It is possible to reduce the thickness of the silicon of 50% Less possibility for electrons to find impurity before they escape A lower quality of silicon is required Higher efficiency Now the panel can convert 20% of the energy of the sulight that falls on it.

9. 10 Will lead solar panels to produce electricity for a price of 8 to 10 cents per Kilowatt-hour. Use of a screen printing technique (much cheaper than the ones used in the past) to attach mirrors to the cells Cells made with cheaper,less pure forms of silicon Decreased by 50% the quantity of silicon used At the moment Suniva has demostrated that it is possible to achieve an efficiency of 20% for solar panels using the screen printing technique. However it has not reduced the thickness of its silicon cells to 50%, not yet reaching the price of 10 cents per Kilowatt- hour for its panels.

10. Technological advances have resulted in lower production costs. Even with lower production costs the solar panels now in the mass market cannot compete with conventional electricity costs. These improved solar panels have yet to be introduced to the mass-market. …

11.  Bullis, K. (2008). More-Efficient Solar Cells. Retrieved December 1st, 2009, from http://www.technologyreview.com/read_article.aspx? ch=specialsections&sc=solar&id=21255 http://www.technologyreview.com/read_article.aspx? ch=specialsections&sc=solar&id=21255  Bullis, K. (2008). Efficient, Cheap Solar Cells. Retrieved December 1st, 2009, from http://www.technologyreview.com/read_article.aspx? ch=specialsections&sc=solar&id=21405 http://www.technologyreview.com/read_article.aspx? ch=specialsections&sc=solar&id=21405

12.  “1” Lake Lite Solar Panels (n.d.). Retrieved December 8th from http://www.boatownersworld.com/lake_lite/solar_panels.htm  “2” MIT Library news (2008). Retrieved December 8th from http://news-libraries.mit.edu/blog/date/2008/01/  “3” Bullis, K. Technology Review: More-Efficient Solar Cells (2008). Retrieved December 8th from http://www.technologyreview.com/read_article.aspx?ch=specialsections&s c=solar&id=21255 http://www.technologyreview.com/read_article.aspx?ch=specialsections&s c=solar&id=21255  “4” Mr Sun clip art- vector clip art online, royalty free & public domain (n.d.). Retrieved December 8th from http://www.clker.com/clipart-13408.html

13.  “5” Suniva – A World Leader in PV Technology : providing high efficiency silicon photovoltaic cells to the solar power industry (n.d.). Retrieved December 8th from http://www.suniva.com/  “6” Day4 Energy Inc (n.d.). Retrieved December 8th from http://www.day4energy.com/  “7” Bullis, K. Technology Review: More-Efficient Solar Cells (2008). Retrieved December 8th from http://www.technologyreview.com/read_article.aspx?ch=specialsections&sc=sol ar&id=21255 http://www.technologyreview.com/read_article.aspx?ch=specialsections&sc=sol ar&id=21255  “8”,10” Tasse>>Mente Critica. (2008). Retrieved December 9th from http://www.mentecritica.net/tag/tasse/  “9” Bullis, K. Technology Review: Efficient,Cheap Solar Cells (2008). Retrieved December 9th from http://www.technologyreview.com/read_article.aspx?ch=specialsections&sc=solar& id=21405