I tried something similar using a 2700mAh LiPoly battery, a 3.4watt solar panel and a USB / Solar LiPoly charger, all purchased from Adafruit for a different pr

I tried something similar using a 2700mAh LiPoly battery, a 3.4watt solar panel and a USB / Solar LiPoly charger, all purchased from Adafruit for a different project. It can power the Pi for about 4 hours, but you'd really want a much larger panel and battery. Also, I was very worried about the potential fire hazard from the LiPoly battery. I will eventually be setting up my camera in a state park, and I don't want to be responsible for starting a brush fire.