how do you decide what d/c voltage to go with?

[kbhale]

Could someone tell me, how do you decide what d/c voltage to go with. My home is tied to the grid but a good third or half the energy I use is in my BBQ kitchen and tool shed. I want to go off grid with the two buildings. I have some 12 volt panels now, about 360 watts.

[fromport]

Could someone tell me, how do you decide what d/c voltage to go with. My home is tied to the grid but a good third or half the energy I use is in my BBQ kitchen and tool shed. I want to go off grid with the two buildings. I have some 12 volt panels now, about 360 watts.

Everything is based on (maximum) usage.

What is the maximum amount of power you will be using at any time ?
That will give you the amps which gives you the voltage.

12 volt system needs 4 x more amps than 48 volt system.

In general: go for 48 volt if possible, saves you on copper (awg wire size) and better to put batteries in series then parallel.