[GBlist] Building one's own solar panel

[Susannah Meininger <susannah@cyber-dyne.com>]

Hi folks --

This is my first real post to the list, although I've been reading it for a 
while.  I recently found out (by cruising eBay) that a person can buy 
pounds of individual solar cells and solder them together to make a 
panel.  It's not something a person would want to do for a client, but have 
any of you done this for your own use?  Is it is easy as it sounds?

Also, it's been a long time since college physics.  I understand that if 
the individual cells are a .5 V, 450 mA each, then to get 12 volts I wire 
48 of them in series, and the result is still 450 mA.  But am I right to 
think that watts = amps x volts, and that if I want, say, 50 watts, then I 
need to wire in parallel 50/12 = 4.17 total amps desired, divided by .450 
amps = 9.26 sets of 48 cells, for a total of 444 cells?  That seems like an 
awful lot, so hopefully my math is wrong.  Any help would be greatly 
appreciated!

-- Susannah (an extremely small-time builder/rehabber in western Oregon, 
who is currently building a small electric vehicle and would like to 
solarize it)


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