Please solar power it, just to be the first and show it can be done with a little 50w panel...
A 50 watt panel would only be enough to power it during the day, and probably not the whole day either.
I'd recommend a 200-300 watt panel, a deep-cycle battery around 80-100 amp-hours, and a charge controller - this way it could run 24/7 only on solar power, worst case scenario that battery could run it for at least a full 24 hours.
how much would this setup cost?? and can i get the stuff at bitcoinstore?
You can get a raspberry pi starter kit with bitcoins at bitcoinin.com. It costs 0.35 - 0.62 coins depending on whether you get just the raspberry pi or the kit.