Question

Why south africa must include renewable energy in its energy mix

Answer 1

South Africa is not a country with an abundance of money, or an abundance of resources that are needed to live. It is very important for them to save as much as they can, and to use as much renewable or recyclable resources as possible. If they run out, that's all for them. They don't have enough money to buy more and it's very hard to get good resources for dirt cheap prices(basically impossible). When using renewable energy in it's mix, it will give them more energy while using less of their supplies to make it. 

Answer 2

Well, here's why.
Fossil fuels are depleting as some of us know and that means we can't rely on Eskom forever. And with renewable energy companies such as Momentous Energy rising up, it won't be long now before you see turbines in your backyard.
The downside is that South Africa still owes millions of dollars to the world bank and surely we can all see that the dept is not getting paid anytime in the foreseeable future, to which I say that we should build water mills, supply ourselves with solar panels and turbines while people are chasing down Zuma. BUT, with fossil fuels depleting, every country wants-needs to get their hands on turbines, solar panels and water mill equipment, but they are getting expensive, bordering from hundreds of thousands to millions of dollars.
So there are advantages and disadvantages of switching to renewable energy, (mostly disadvantages) but if we don't switch now, we'll look like cavemen compared to Iceland and all the others intellectual countries that are already running on almost 100% renewable energy.