Project 16 (Angel, Nico and Nick) Data!
Manufacturing of Solar Cells and Necessary Components:
The manufacturing process can be broken down into the following steps (click the link above below for further details):
- Purifying the silicon
- Making single-crystal silicon
- Making silicon wafers
- “doping” – adding of impurities: phosphorous gas burrows into nearly melted silicon
- placing electrical contacts – connect to the receiver of the produced current
- the anti-reflective coating
- encapsulating the cell
http://www.madehow.com/Volume-1/Solar-Cell.html
See also youtube video from the discovery channel that could be incorporated into the PowerPoint:
http://www.youtube.com/watch?v=qYeynLy6pj8
Rough Cost of Solar Cells:
Efficiency of silicon based solar panels, and other, newer varieties of photovoltaic cells:
-Colarado State University has a large solar power generator that helps to power the university. Their field of solar panels in terms of efficiency can be viewed here: http://www.fm.colostate.edu/sustain/index.cfm?page=projects/energy
Basic results of their efficiency include the following:
- Project Surface Area: 30 Acres
- Solar Plant Capacity: 5,300 kWdc
- Date of Completion: December 2010
- Annual Energy Output: 8,500,000 kWh
- Number of Solar Panels: 23,049
- Number of Watts per Panel: 230 W
- Number of Inverters: 10
Generates equivalent electricity to power 949 homes
The following link also contains tables for different efficiencies for different varieties of solar panels (note high efficiency in cells that are not yet able to be mass produced):
http://onlinelibrary.wiley.com/doi/10.1002/pip.1021/full
Potential Issues in cost and efficiency:
-Ronna Kelly, director of UC Energy Institute argues that solar panels do not pay for themselves, and in fact constitute a poor investment choice: “the cost for an installation ranges from nearly $86,000 to $91,000, while the value of the power produced ranges from $19,000 to $51,000.”
-Currently this is a high estimate for installation, but even liberal estimates believe it would take over a decade to recapture the initial investment. (SOURCE: NICO).
The science seems to overwhelmingly support that even with the contemporary (relatively inefficient) rates of converting photons into electricity will ultimately lead to the: “reduction of the emissions of the greenhouse gases (mainlyCO2, NOx) and prevention of toxic gas emissions(SO2, particulates)” – according to Tsoutsos et al (2005).
-Include table citing reduced levels of carbon emissions on page 290.
Citation for more data:
Environmental impacts from the solar energy technologies
Tsoutsos,Theocharis; Frantzeskaki,Niki; Gekas,Vassilis
Energy Policy, 2005, 33, 3, 289-296
Physics of photovoltaics: how it converts sunlight to energy:
Political implications of solar panels – can they help us reduce our dependence on foreign fossil fuels?
The Department of Energy writes that they plan to make solar energy products cost-competitive by 2020. However, this will be of little to no use. Even if they do become cost-competitive people will still be leary of them and the fact is that solar products are not much less dangerous than energy sources now. One problem with receiving the benefits offered by the federal government is that regulations are done on a state level rather than federal. If the state does not approve certain aspects, then any federal benefits remain void.
http://www.cleansolarliving.com/webpage.php?page=24
http://www1.eere.energy.gov/solar/
Future of photovoltaic technology:
Diaz, Alonzo, et al. (2002) write that in certain laboratory, experimental settings, extremely high concentration photovoltaic cells have achieved efficiencies of up to
A company in California called Nanosolar (2007) has recently been mass-producing a thin film capable of producing high levels of energy from sunlight at a competitive cost of one dollar per watt. Compared to usual solar cells that require glass, aluminum, copper and silicon, these cells are a thin film consisting of five layers:
1. Aluminum foil for stability.
2. Molybdenum Electrode
3. CIGS absorber / semi-conductor- an ink made of a mix of copper, indium, gallium, and selenium.
4. as in the old solar model a P/N junction, a semi-conductor that doesn’t absorb light.
5. Lastly, a clear zinc oxide semi-conductor.
Check the animation!
http://www.popsci.com/popsci/flat/bown/2007/green/item_59.html