off-grid solar/wind powered greenhouse

 Hello DIYers,
I am planning on building a simple greenhouse (hoop-house) this spring. The construction will be for an 8'x12'x8'H design. Building this part is wonderfully easy. The hard part is building the off-grid power to supply power to the greenhouse fans and hydroponic pump(s). I'm not sure where to start with the plans. 

Here is what I am needing some guidance:
Do I build a PV panel then design my electrical needs around that...or vice-versa?? (I have forty 2W solar cells on order)
I know i will need batteries...how many 12V batteries do I need? Type?
What is the best configuration for the batteries?
Should I use a DC hydro pump or AC hydro pump?
DC or AC fan for cooling?
Future plans include using an arduino to be the main controller....

Please keep in mind that this is a small(ish) hobby greenhouse and I hope to build it to be fully off-grid, at least for the summer months. I have the time to build it, but don't have the know-how for fully designing it (electrical stuff confuses and scares the crap outta me). I'm not against keeping the price low, but am willing to spend a few extra bucks to make sure it's designed right.

milk cart battery's are old car battery's golf cart battery's all pretty easy to find ..and myself i used big PC case fans bigger the better might get them of a scrap heap are recycling center keep your power supply dc because to run a inverter uses power before you get to see the benefit what a waist good look guys care gals