I have to agree with him, the reliability was a problem, when I was there. They have a system called "Loadshedding" where they switch off whole suburbs to reduce the load on their network. {It seems as though the provider, cannot supply enough electricity} Luckily for me, the hotel where I stayed, had backup generators, so we still had power, when the outages occured.
The receptionist said, it's a daily thing, and it can happen up to 3 times a day.... 2 hours per event, without electricity. {This is not provitable at all for miners, who wants 24/7 electricity, and using backup generators, will decrease profits even more... due to the increased cost of gas.}
The climate is also a bit warm in summer, for mining to be viable. {Cooling cost will increase} I compare that to Canada and China.
Still a great place, and a must for everyone to see.
.... I have been to a place called, Sun City and it was a great adventure.
.... The people are also more friendly, than in most places in Europe.