What size of solar system

[Sunking]

I bought my off grid cabin in the foothills of Washington State in July. All of the appliances are gas so we don't use a lot of electricity. It's a weekend cabin with a week or two of vacation times throughout the year. I'm trying to get an idea of what size and type of system I should be looking at to keep the batteries charged so I don't have to fire up the generator and while it's not being used..

There is the conflict. you stated you need 2 Kwh/day while there for up to 3 days. If you get a panel wattage just large enough to maintain the batteries full charge, you are going to have to use the generator. In addition not sure where in the state of WS you are talking about, but if on the west side of the Cascades your solar insolation is really poor in winter months and would almost certainly require and generator if you stayed there in winter regardless of panel wattage.

I can give you a start by at least suggesting a Morningstar Sunsaver MPPT controller made for 12 and 24 volt systems at 15 amps. At 24 volt battery can input up to 400 watts. Do not use battery panels, use grid tied panels as they cost half as much as battery panels and use at least 2 panels wired in series. That pretty much means either 2 150 or 200 watt panels for a total wattage of 300 or 400 watts. It is not enough to properly charge up the batteries, but more than adequate to refresh some of the power while in use up there. At any rate you will still need the genny for maintenance and cloudy days like any off-grid system.

Forget 12 volts, that is for toys and RV's.

[solar pete]

I bought my off grid cabin in the foothills of Washington State in July. All of the appliances are gas so we don't use a lot of electricity. It's a weekend cabin with a week or two of vacation times throughout the year. I'm trying to get an idea of what size and type of system I should be looking at to keep the batteries charged so I don't have to fire up the generator and while it's not being used.

I have 12-6volt batteries wired in series and parallel for a 12 volt system with 720 total amp hours and a 2400 watt Xantrex inverter. I only have a chandelier and a couple lamps plus a TV and DVD player. I have estimated the usage well on the high end so I'm figuring we use 6 KWH average on a 3 day weekend up there. I've been reading through the threads and some of it goes over my head but I'm learning more as I read more. I'm just looking for some ideas to hopefully get a solar system setup next spring. Any advice is much appreciated.

Hi Jaust and welcome to solar panel talk

[Sunking]

I need some new 6 volt batteries for my golf cart. Where is this cabin located. I should be able to find it easily with panels on top.

[Jaust]

I bought my off grid cabin in the foothills of Washington State in July. All of the appliances are gas so we don't use a lot of electricity. It's a weekend cabin with a week or two of vacation times throughout the year. I'm trying to get an idea of what size and type of system I should be looking at to keep the batteries charged so I don't have to fire up the generator and while it's not being used.

I have 12-6volt batteries wired in series and parallel for a 12 volt system with 720 total amp hours and a 2400 watt Xantrex inverter. I only have a chandelier and a couple lamps plus a TV and DVD player. I have estimated the usage well on the high end so I'm figuring we use 6 KWH average on a 3 day weekend up there. I've been reading through the threads and some of it goes over my head but I'm learning more as I read more. I'm just looking for some ideas to hopefully get a solar system setup next spring. Any advice is much appreciated.