Large users are mostly mining, and they've been heavily downsizing, and investing into renewables and storage to lower their load.
Smelters are not profitable here anymore at current Eskom rates, so expect those to vanish once their contracts for cheap electricity run out a la Richards Bay.
Residential load is mostly heating - that can be reduced by an easy 30% just by promoting solar heating, and gas cooking.
LED lighting will also reduce usage once more muni's roll that out. Street lighting is a major power user, and LED lighting can reduce that to about <10% of original power usage.
Pool pumps can be moved to variable speed pumps at owners cost - this is a fairly straightforward proposition for most pool owners if you compare electricity cost savings on a variable pump. Solar PV is also rather good for that too.
Solar PV is being rolled out as fast as possible on a corporate level, as its cheaper than buying from Eskom, so daytime use is dropping also.
We don't need Nuclear, but we do need more storage to flatten out non-dispatchable power curves.