Thanks everyone for shedding such light on it. I think I have enough info
to get started


"Bryan Martin" wrote in message
...
The unit I will be using is 12V 0.5A

12V X 0.5A = 6 Watts
6W x 24hours = 144 Watts per day
144W / 12V = 12 amp hours

Now given a battery with 110 amp hours
(http://www.defender.com/product.jsp?path=-1|328|51495|306219&id=51496)

We should only draw the battery down 50% so we will actually only get

110 / 2 = 55 amp hours

12 amp hours needed / 55 amp hours available = 4.58 days
so with this battery we have enough juice to potentially run our unit for
4.58 days w/out charging.

Now if the above is not correct then please explain. And the next
question is how would I now figure out approx how large of a panel I would
need to keep the battery charged. I am really looking for the formula and
a understanding of how you got from A to B as oppose to "this panel should
work".


--
Poor planning on your part does not constitute an emergency on my part.