I have no experience and don't know where to start. I would like to do a full off grid system.

I am not sure where 240v came into play here?
Curious what you would consider bringing into play to run a house and a large garage/workshop. 208/3-phase? The problem is, most commonly available high draw electrical devices are 240v: hwh, hvac, dryer, range, ... Devices that will run at 120/240 (pool pump, well pump, power supplies ...) are generally more efficient at 240v as well. I have a small rack of computer gear here, which is all 240v capable, it's on my agenda to move it to a 240v circuit.
 
Sol-ark has a 60k but it's for 480V 3 phase
The EG4 / 1812 manual says you can stack up to 10 to get to 120KW. That would be 500A/240V, s 8 would get you to 400A. You'd probably have to carpet a square mile of property with solar panels and find a place to put in 8-16 racks of batteries, but you could do it. Generally the battery is about time, but if you are actually going to get a 400A demand, your going to need significant engineering, as you may need to draw around 2000A/50v from your batteries at any given point. I'd probably pair/quad independent battery sets bused to inverter's in pairs. It would be fun to build out. The problem with the EG4's is if you lose an inverter the whole system shuts down. Anybody have any experience with parallel Sol-Ark or other brands that don't fall over if you shut one off?
 
The EG4 / 1812 manual says you can stack up to 10 to get to 120KW. That would be 500A/240V, s 8 would get you to 400A. You'd probably have to carpet a square mile of property with solar panels and find a place to put in 8-16 racks of batteries, but you could do it. Generally the battery is about time, but if you are actually going to get a 400A demand, your going to need significant engineering, as you may need to draw around 2000A/50v from your batteries at any given point.

At higher wattage, you might want high voltage battery (400V or 1000V). Most I've seen listed are 3-phase, 230/400Y or 277/480Y.
SMA sells one in Europe that is 75kW. In the US I only see multi-MW models from them.

The problem with the EG4's is if you lose an inverter the whole system shuts down. Anybody have any experience with parallel Sol-Ark or other brands that don't fall over if you shut one off?

Sunny Island is 120V, 6kW and can be connected all in parallel, or parallel/series for 120/240V split-phase.
It will continue operating with some disconnected.

Three can be connected for 120/208Y 3-phase (18kW), and optional whether it shuts off for lost phase or continues operating.
Four of those can be connected as "multi-cluster" for 72kW.


If OP can get by with about 100A 240V steady-state, surge to 200A for a couple seconds, then stacked inverters with 48V battery should work.
But as noted by others, it is more likely to have steady state loads of a couple kW, or whatever A/C draws.
What gets tough is providing enough battery for 24/7 A/C. If A/C is only needed when there is direct sunshine, easy enough to power with PV panels. Small battery for other loads at night. That's what I have.
 
What gets tough is providing enough battery for 24/7 A/C. If A/C is only needed when there is direct sunshine, easy enough to power with PV panels. Small battery for other loads at night. That's what I have.
I'm Jealous. The low is going to be 90 again this evening. The hotter the nighttime low, significantly impacts my time on grid. I need more battery.
 
My A/C is small (so is house), and mild San Jose weather.
A 15A breaker powers the A/C.
I have about 15kW of panels, 10kW of GT PV inverter, 20kWh of battery (14kW usable).

It is a small battery slapped on a large net metering system.
Panels are mostly aimed at 2:00 PM, added some aimed 4:00 PM. Originally optimized for backfeeding grid back when Noon - 6:00 PM was peak rates, not ideal for off-grid where power all day is useful.

I suggest more PV of multiple orientation, before more battery.
 
You said...

I am hoping to have at least 100 amps for the garage and run a 200 amp sub panel to the house once it is built. The garage will be where the inverters and batteries are located.
Did you mean you would need a 200A main panel and a 100A sub panel? You can't get 200A from a 100A panel.

My place has a 200A on the main house with a 100A sub panel in the garage where the inverters are. I would just have to run the A/C output of the inverters over to the Main panel to power the garage and the house.
 
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