Reading and logging solar panel energy with Arduino

I'm trying to measure how much energy my little solar panel (one from an LED Keychain) produces thru-out the day, so I was thinking of connecting an Arduino to it to log the energy every, say, 10 minutes, and then save that to EEPROM. Every hour is also fine, I imagine that would take less space in the EEPROM. How would I go about this? I think I would use the Analog pins and measure the energy coming from the solar panel, but I'm not sure what code to use for this.

Er... am I in the right section? I'm not sure what this should be under...

Is there any way to do this? I just want to know how much energy the solar panel produces. If I can't, that's fine.

By energy, you mean watts? or do you mean Voltage?.

Voltage would be simple enough, in order to measure power/watts you'd need a shunt resistor and measure the voltage drop.

I'm just trying to measure voltage (no way this thing could produce watts).

Of course it produces watts, probably in the milliwatt range ..

Gnd to gnd on the solar panel, postive to an analog input pin eg a0, read the value (0-1024) and that's it 1024/voltage gives your voltage.

cjdelphi: Gnd to gnd on the solar panel, postive to an analog input pin eg a0, read the value (0-1024) and that's it 1024/voltage gives your voltage.

Knowing the open circuit voltage of the solar cell isn't very valuable.

Chagrin:

cjdelphi: Gnd to gnd on the solar panel, postive to an analog input pin eg a0, read the value (0-1024) and that's it 1024/voltage gives your voltage.

Knowing the open circuit voltage of the solar cell isn't very valuable.

Place a 1k ohm resistor between across the solar panel terminals then measure the voltage.