ugrading 12v system

eva

Hi, I have been running my off-grid house in Baja sur with 4-135 Kyocera panels, xantrex charge controller,4- T1O5s and a magnum 2O12 modified sine inverter.  We just enlarged the house and are going to a 35OO watt system with a pure sine wave inverter. The guy that keeps track of things when we are not here wants us to go to a Morningstar mppt inverter so he can track the system better plus we will be keeping our 135s in addition to the new larger panels. We plan on getting an electric energy star fridge, and very occasional running of AC during the day in the hotter months. My question is, is it best to change to a 24v system? The guy that installed our original system prefers 12v for it simplicity. But I thought 24v would be more efficient. My knowledge is limited but I am trying to improve there. Our panels are only 15 ft from the rest of the system.  I plan on selling the old component or bartering them off. Thanks for any help.  I need a good argument to present to the spouse and the previous installer who is a friend.

mike95490

If you are going to sustain loads over 1,000w, you should be at 24V.  Over 2,000w sustained (fridge and AC both on) you need to look at a 48V system to keep DC amps at manageable levels.