Off Grid Cabin

[Matt63]

My off grid system needs to support a well, 2 zone mini split, lights and a refrigerator. My plan is to have two 14 panel solar arrays connected together in parallel and feed into the inverter. Each array will consist of 14-260watt (30.7 VDC, 8.50 Amp) panels in series (429 VDC @ 8.5 A each array, total 429VDC at 17 A). Optionally I could wire 14 sets of two parallels (wired in parallel) with each set connected in series through a combination box. What arrangement would work better for a full sun land based system? Which inverter woudl be better the Sol-Ark 12K inverter or EG4 18K inverter?

 

[dcg9381]

EG4 = "seller support" only. They're also fairly high idle draw.
Sol-Ark = Engineering support

What's going to matter a lot more than the panels is your "battery buffer" - IE battery capacity. Even in CA, you need to plan for 3-4 days of no solar being available. So it's really a lot more about how much power you can store.

A lot of this is going to be "how do you use it" that can't be determined by math up front. Design it to be expanded. And if it's "critical use" - make sure you have a generator charge option.

 

[Matt63]

EG4 = "seller support" only. They're also fairly high idle draw.
Sol-Ark = Engineering support

What's going to matter a lot more than the panels is your "battery buffer" - IE battery capacity. Even in CA, you need to plan for 3-4 days of no solar being available. So it's really a lot more about how much power you can store.

A lot of this is going to be "how do you use it" that can't be determined by math up front. Design it to be expanded. And if it's "critical use" - make sure you have a generator charge option.

I have two gas generators as back up. I was looking at the battery backup SOL 25kWh 48Volt or EG4 lifepower 30.72kWh 48 volt battery. Which is better?

 

[dcg9381]

I have two gas generators as back up.

Make sure they work with the inverters. The only way to really do this is to test.
EG4 has a "chargeverter" which is designed to charge their battery systems with "dirty" generator power - it's also a work around.

I have EG4 LL V2 batteries. I've had no issue with them other than their "communication" bugs with their own BMS and I see that they have other bugs with other monitoring systems (some of which were fixed by firmware recently). I'll let someone else chime in on which are "better".

 

[Matt63]

Thanks for the heads up.