I want to build my own off-grid system but confused with what sizes (V, I) to get.
I want to run a 24v system powering 4.4kWh/day. I have 4 hours of usable sunlight a day and space for panels and equipment is not an issue (within reason).
Looking at the calculations:
Electrics = 220v @ 60Hz
Load = 4.4kWh/day
Sunlight = 4 hrs
The PV array I then calculate at:
PV Array = 4400Wh / 4hrs = 1100W (10 x 100w panels)
The batteries I then work out at:
4400W / 24v = 184Ah / 80% discharge = 220Ah
A battery example  - 24v 220Ah deep-cycle li-ion (2000times(80%DOD))
* or if you want to go down building your own battery pack with 18650's - 7 in series (to get 24v) x 55 packs in parallel (to get 220Ah).
The calculation problems I cant find anyone explaining on Google is:
a) What size charge controller do I need? I see options from 10A to 100A. b) What size inverter do I need? I see options up from 100W to 3000W and more. c) Does the PV array not need to be x2 the size so it can power the house and charge the batteries at the same time during the day?