Gerrit1984

Go Youtube Bluenova and go check the video where they open one of that Super caps systems that is selling in SA. I will not spend my money on that if it looks so bad inside. 
 

Your maths is a bit dodgy here.
100Ah at say 50 V = 5kWh, so 80kWh = 1600Ah usable battery power.
So battery size:
LA at 50% DOD = 3200Ah & lithiums at 80% DOD = 2000Ah.

1st you need to determine what your usage are between 16:00 and 8:00 in summertime and also how the sun will behave in wintertime, I don’t have that data yet and will only know after the next winter. 
You will need a bank to supply you with enough kWh to go through the time there is no sun. Let’s say it is not raining, then you need enough battery backup to carry you through the night.
Problem is that winter time and summer time will differ, also what you will use will differ. If you use the batteries with heavy loads it might shorten their lifetime, in other words it might cause it to turn cycles quicker. This is the most expensive portion of your system, so you will need a couple of things added to get you totally off-grid, for example gas/solar geyser, but solar geyser might want to use electricity during the early mornings. Gas oven, etc.
 
Everyone have their favorite when it come to batteries, I like batteries that have an indication of SOC, such as Narada or Pylontech. New batteries such as Dyness (which is basically Pylontech) also have this indication with LED’s on the front indicating SOC. These are the lithium-ion batteries. With gel batteries I don’t know anything except that you need a proper battery monitoring system and you can only discharge 50%, therefore you need way more batteries, also that you can’t just add on and they also don’t have the lifetime that you would expect of them. The Pylontech’s came with a 7 year warranty + 3 year extended warranty by registering them on Pylontech’s website. They say 6000 cycles for 80% DOD, and 4500 cycles for 90% DOD, my batteries never went below 20% thus far. My cycles turn between 24 hours and 47-48 hours. I am currently on cycle 30 and have used the batteries for 40 days.
I currently have 4x US3000 Pylontech 48v batteries, I believe they are 70A max charge/discharge, 3.5KW x 4 with usable 3.2KW x 4. I have not have any problems so far with these batteries, even when I recently accidentally ran the geyser/s off them. Meaning that my batteries have never given me an alarm or error and they have never shut themselves down. I would like to add 1 or 2 new batteries before next winter, will see when the time come.
The difference is that we don’t have continuous loads of more than 1000w per hour from 16:00 to 08:45. 
I designed my system to produce 42KwH in 6 hours of sunlight (without any losses), so the panels will handle most of the loads when the sun shine. My current usage is between 32-36kWh per day.
Currently we are using the grid (in this rain), so my batteries are fully charged for most of the day, this is to prevent us sitting in darkness with the current load shedding schedules that have just been changed to stage 6.

Great, I am glad you are sorted.