How much advance warning will you get? You need 48 kWh + charge/discharge losses. So if you get 8 hours of sunshine on 100 W per square metre panels you need

How much advance warning will you get? You need 48 kWh + charge/discharge losses. So if you get 8 hours of sunshine on 100 W per square metre panels you need 48/(8 * 0.1) square metres to charge in one day, that is 60 square metre. Or you can use two months to charge and one square metre of solar panels. More panels charge in less time. Then you need a battery about the size of that in a medium sized electric car if you use lithium ion or lithium iron phosphate. If you use lead acid batteries which are probably easier to obtain in Africa, and cheaper, you will need something like 50 car batteries or equivalent because each on has a capacity of about 1 kWh depending on the size of the battery. Don't actually use car batteries, there are batteries specifically designed for use with UPSes How portable does this installation need to be? If it needs to be at all mobile it really would be simpler and a lot cheaper to use a 2 kW petrol or diesel generator So to summarize you need to decide how long you can wait for the battery to charge, how often you want to go offline, how big a solar array and battery you can afford.