When I said we need a 7kW system, I meant PV input power to the charge controller, not output. There's room for 16 x 455W panels on the sun-facing side of my roof, so that's 7280W (theoretical max, obviously). That's all the room we have for now, so that's about the best we can do. I want an AIO with hefty VOC so the whole array will feed into a single MPP without a combiner box if possible, but I also want 2 x MPPs so I can add another array later (extend back porch, put panels on that roof). We currently use about 5kW/day, but we're wanting to build a system that would support more like 25kW/day. We get about 4.9-5.1 sun hours a day here, so if we figure about 30% overall system loss, that would net us the 25kW we need. We would only use that much in the height of summer. The rest of the year, we would get some autonomy.
There's no utility around these parts. We're off-grid, baby! That said, I can't figure out how to build a system with 2-3 days of autonomy within my budget, so I'm sure we'll still end up using the generator from time to time. We have 4 of them. Currently, we run the generator several hours per day on most days, so reducing it to once in a while would be awesome.
We have the budget for the project right now, but we have to clear a bunch of trees first, so we have some time. We have not calculated federal tax rebates into the equation.
I have similar goals and am currently researching to build a similar set up.
I go back and forth more than once a day on which route I’ll take, with most changes typically in regards to inverters. I feel pretty content with panel and battery choices.
If I had a money tree I would have already ordered stacked Midnite Rosie’s and 2 hawkes bay 120s (one Barcelona would probably do, but redundancy sounds nice)
Second would likely be a pair of schneider 6848s with their kit that includes the PDP and other boxes
Seemingly third, but I’m still trying to learn more about as it doesn’t seem as common in pure off grid, is a pair of Outback Radian 8048s
I think the main difference in our system plans are inverter capacity.
Low frequency is the only option for my system (mentally hahaha)
In the last few weeks I’ve really become keen on reading threads with hedges, Texas cowboy, zwy, 420ohms, offgridforgood, and of course TimsElectric participating in them. Such fun, friendly, and beneficial banter it seems on a regular basis.
And at least half of them seem to suffer analysis paralysis as significantly as I do ?
Anyways, 30k in cash up front is painful; so I’m trying to find alternatives (my initial cost projection pre tax credit)
I can’t quite get myself to depend on only one inverter, regardless of size (and the big ones are HF anyways) but I do think I would go with a single schneider before ANY HF option, including sol-ark (mostly their forum presence and business model)
This leads me to the plethora of 6048 variants. Whether it’s sungold, mpp, eg4, or other. Important to me is one of the refreshes that has a high VOC capacity. And I guess the LF growatt can’t be stacked either.
My plan is 10-14k PV with ~400w panels ground mount (40-50c/watt). 40kwh of eg4 battery (8 of them) and then figure out the inverter side of things
But for purely rough numbers for your system, 4k for panels, 1500 inverter, and 4 Lifepo4 batteries for 6k, and 2k for misc. would get you pretty close to your goal and in budget pre tax rebate. I’m sure other incidentals would be at play in the napkin math.
And would allow you to stack inverters and/or add PV later as well as increase battery
