I've found that for a 12v system, as opposed to 120v, the wire needs to be stranded; because, umm, well that info is lost in my memory bank somewhere. Heat dissapation? More paths to conduct? Low resistance? I may need a larger gauge wire for my mind's bank!
This website has a wire sizing calculator that is just awesome!
The real question is where to buy the wire. Home Depot, to my dismay, doesn't carry any low voltage wire that is a lower than 12/2. I bought the 12/2 for the gate opener....cheap, cheap! Amazon.com even cheaper.
I'm thinking I'm gonna put my panels on my roof and running them to my batteries may be up to 30', so at 12v with 10amps max for my two panels at a distance of 30' I'm supposed to get 8 gauge wire. Very'spensive! If I can keep the distance to 21' then I need 10 gauge...and at 13' it's 12 gauge. Maybe I should throw the battery bank on top of the roof also; I could build a little dormer. Pffff.
On Amazon, Hinkley 10-2 is less than $1 per foot, but you have to buy $250 feet. Anyone wanna coop? Ok...just found Hinkley 8-2 100 feet is $239. Ouch!
To lessen the distance, therefore the cost of the wire, I'd have to either move the battery bank or the panels. I have to put them on the roof, or atleast somewhere that the coodie coddlers can't easily get to them. How about a loft bed type of thing, but a bed of sorts for the batteries. I can see drilling through the roof, or even the facia and having a distance of as little as 5 feet. Gee....with 5' distance, I would need 16/2...A building I will go, a building I will go.....hi ho the dairy oh...wait....have to build a loft ladder too.
Will it never end? Aaaaaaaaa hahahahahhahaaaaaa