Powering Arduino directly from 12v solar panel?

As the title says can I power my Arduino directly from a small 3w 12v solar panel? I only need power during the day to monitor water level in a tank.

So the question is, can I solder the leads from the solar panel directly to the Arduino or will this give me problems?

Basically no. A solar panel is a complex voltage/current device. That might give startup problems during dusk/dawn. An unloaded 12volt panel will also produce >18volt in full sun. Too much for most Arduinos. It might be better to charge a battery with the panel, and power the Arduino from the battery. Post specs of all the hardware if you want better advice. Leo..

thanks what i thought allready.