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View Full Version : Good solar cells, but fragile...


e-sailpilot86
Jul 17, 2002, 01:58 AM
Just using in head math, ten of these solar cells will put out about 5 watts max, and weigh only 23 grams total. I did some work, and I think the DC 5-2.4 with steep gearing is a good choice, and maybe the firefly as well. May not be totally economical, but consider this:
use thirty solar cells, and yes, you spend a lot, but you get about 15 watts at the maximum, at about 70 grams. That's likely enough to power an IPS drive system. Take a look anyway, this is a good project idea if your club could use some publicity!

Satellite cells (http://www.solarcell.net/the_solar_cell_company_updated_005.htm)
Enjoy!

Although some say you should find the amount of power you need, then double it, there might be an exception here. Higher efficiency gives more power for the weight. I think these use gallium arsenide as the semiconductor, or whatever makes the cell work! Found that word while seaching for solar powered information... It'd be nice if I knew what was so nice about it:D .

e-sailpilot86
Jul 17, 2002, 02:18 AM
I hope this motocalc prediction is somewhat encouraging... For lower power consumption I originally set the gear ratio to 21:1, drew a predicted 2.2 watts or so. So I raised the bar a bit and it's down to a 15:1, not being conservative. At lower throttle settings, the total system efficiency went up to about 77%, at flying speed.

e-sailpilot86
Jul 17, 2002, 02:23 AM
and again...

Realize these are just predictions, and even if they fell below this level of expectancy, it's still likely the thing would fly. Mylar, high grade balsa, ultra light weight techniques, etc.

Imagine the lithiums are changed to solar cells, and leave the weight the same.