| | Category | EV | P24 | Silicone versus EVA: Comparing Two Methods of Solar Cell |
| | Encapsulation |
| | Abstract | The purpose of this experiment is to compare the Quantum efficiency, |
| | actual efficiency, and power output of silicone and EVA photovoltaic solar |
| | cell encapsulants in order to determine which of them should be more |
| | frequent in commercial use. |
| | The common element used in the industry today for encapsulation is |
| | Ethylene Vinyl- Acetate, or EVA. This organic copolymer comes in sheets |
| | and is relatively easy to use. The problem with EVA is that, since it is |
| | organic, it needs stabilizers to prevent from browning. The stabilizers |
| | absorb all UV light, which on the solar spectrum, in 0 nm to 400 nm. That is |
| | a considerable amount of light that is not even allowed to get to the cell. A |
| | possible solution to this problem is to replace the EVA encapsulant with |
| | silicone, a polymer of silicon that includes carbon, hydrogen, and others. |
| | Silicone comes in a gel and does not require the use of stabilizers. This |
| | means that UV light can reach the cell and be used. |
| | The hypothesized result is that the silicone encapsulation will have a |
| | greater performance than the EVA when tested. |
| | 3 Cells of each category (Silicone-encapsulated, EVA-encapsulated, and |
| | bare) were tested multiple times for quantum efficiency, actual efficiency, |
| | and power output before and after encapsulation and differences were |
| | measured and charted. |
| | In conclusion, the hypothesis was supported by the data. Silicone did in |
| | fact out-perform EVA overall, which leads to the assumption that silicone |
| | should replace EVA as the popular PV cell encapsulant. This also leads to |
| | thoughts about the future. Silicone has a higher performance and also |
| | lasts longer, which suggests that it is most definitely the ideal material and |
| | will pay for itself in years to come. In the future, it would be beneficial to |
| | look at selective vs. homogeneous emitters as well as back contact cells. |
| | Bibliography | Borgers, Gaëtan. Inline Process- Dow Corning Silicone Encapsulation |
| | Solution. Rep. Midland, MI: Dow Corning Solar, 2009. Print. |
| | Ethylene- Vinyl Acetate. Wikipedia. Web. |
| | <http://en.wikipedia.org/wiki/Ethylene-vinyl_acetate>. |
| | External Quantum Efficiency of a solar cell. Wikipedia. Web. |
| | <http://en.wikipedia.org/wiki/External_quantum_efficiency_of_a_solar_cell |
| | >. |
| | Ketola, Barry, Keith R. McIntosh, Ann Norris, and Mary K. Tomalia. |
| | Silicones For Photovoltaic Encapsulation. Dow Corning Corporation, |
| | Midland Michigan; Centre for Sustainable Energy Systems,, 2008. Web. |
| | <http://www.dowcorning.com/content/publishedlit/06-1023-01.pdf>. |
| | Mulligan, William P., Doug H. Rose, Michael J. Cudzinovic, Denis M. De |
| | Ceuster, Keith R. McIntosh, David D. Smith, and Richard M. Swanson. |
| | MANUFACTURE OF SOLAR CELLS WITH 21% EFFICIENCY. SunPower |
| | Corporation. Web. |
| | <http://www.tayloredge.com/reference/Electronics/Photonics/HighEfficien |
| | cySolarCells.pdf>. |
| | Ohl, Sybil, and G. Hahn. Increased Internal Quantum Efficiency of |
| | Encapsulated Solar Cells by Using Two-Component Silicone as |
| | Encapsulant Material. University of Konstanz, Department of Physics, |
| | Konstanz, Germany; Fraunhofer Institute for Solar Energy Systems, |