There are many facrtors to oncider in sizing a battery bank, A/h alone is not enough, voltage comes into it then we have KW's of stored capacity.
Just a few..
Type of battery.
System voltage.
Stored capacity Verses number of days autonomy.
How deep you are prepared to discharge them daily and those extended periods with little incomming power to recharge.
The above goes to life expectancy of batteries.
Maxium load you expect to draw, ie starting a pump/fridge etc and therefore inverter size.
Where you live ie what are your climatic conditions, which will affect your loads.
Who you live with, dogs are less demanding on power than wives.
And so it goes on.....
Anyway as I said on irc full points to Woof for taking the trouble to produce and post a monthly pole.
allan down under
A life lived in fear is a life half lived.