This is a whole-house off-grid system. The EG4 off-grid inverter can take 8,000W of solar power and deliver 6,000W of power. It combines a charge controller, inverter, and battery charger in one. It can also connect to the grid, but it cannot back-feed into the grid, making it an off-grid hybrid inverter. We also have a backup inverter generator for winter when it’s been cloudy for several days.
These are the specs of the solar panel:
- Rated Power: 540W
- Open circuit voltage (VOC): 48.57 V
- Max power voltage (VMP): 41.49 V
- Short circuit current (ISC): 13.70 A
Calculating the max amount of solar panels in a series string:
480VDC/((48.57Voc ×1.25))=7.9 panels in series max
We can have a 7S2P solar panel setup. That is, 7 panels in series are paralleled with another 7, for a total of 14 solar panels, each 540W, for a total of 7,560W of solar. The PV input can take a maximum of 8,000W, so we are close to the maximum.
Next, we will calculate the wire size from the solar panels to the inverter, which is 100 feet or 30 meters. Since we have two mppt inputs, we do not need to combine the strings. We need two 100-foot PV wire sets.
We need a minimum wire size of 14AWG or 2.5mm² PV wire. Since the smallest PV wire is 12AWG (4mm²), we will use these.
This system uses six server rack batteries for 30kW of storage.
The generator has a power output of 7,600W on gasoline and 7,200W on propane. Since you will be using propane for cooking, we will use 7,200W. It’s recommended to run the generator at 70% of its maximum output for fuel efficiency and noise reduction.
7,200W ×0.7=5040W
We can adjust the settings for the generator to a max charging power of 5040 watts.