Built my first solar panel

[tonig123]

Hi,

I've just finished installing my first home-made solar panel. It's made from 32 cells bought from siliconsolar.com. The cells are 0.55v, 2200 mA. Am I correct in my calculations? :

32 x 0.55v = 17.6 v at 2.2 Amp would make for a 38.72 Watt panel.

I've measured the open circuit volts and it does get around 17v so it seems to be wired correctly.

At the moment i'm not seeing more that 0.50 amps charging a 12v battery, on a great sunny day. I wonder what is wrong.

[Flux]

Normal convention is 36 cells. About 21v oc. 17v at peak power point.

If you can find a low battery that is at 12v or below you will likely see more amps.

Flux

[AbyssUnderground]

What is the short circuit current? That might give you a better idea of its maximum current. (Remember the SCC wont be the current you get into a battery).

[tonig123]

Right now its putting 12.20v into the battery at 0.55 amps.

I've tried hooking the panel to a 12v bulb and the amps reach 1.45 so I guess its the battery thats not pulling the amps in.