I am reading on how to calculate the minimum required battery bank to support my intended project. Going by the usual 5hrs peak solar period, I concluded on a 200KW solar solution for the client. They consume approximately 30,000kWh monthly.
When I run a profile on their usage, it came out they had an average load of a little less than 28kW. I suggested they used the on grid solution but because of the unstable power supply in our region, they insist on going with the hybrid solution that would not shut down whenever the grid goes down.
Could you please help me with the formula for calculating the kWh battery size for a 15-hour stand-by period especially for the night? They actually want to be independent of grid.
Secondly, how helpful are these power walls on the market? I tried contacting Tesla to sell me a powerwall but they would not go out of America and some parts of the globe. I found OptalmaxNano and Polinovel who are ready to sell. Do you have any information on these products?