Why the shortage?

Are there price controls on CO2 in South Africa, or something?

Well, there are price controls on some things, most notably petrol. (Heaven knows why). I think the key to understanding probably comes in the words "The major supplier of CO2 in South Africa". That is, there is either a de facto or de jure monopoly. Probably we blame past or present government industrial policy. (In truth though, I have no idea. I just saw these signs on refrigerators while I was there. Despite their presence, I never had any problem buying a Coke. (In fact, I have never been anywhere in the entire world where I had difficulty buying a Coke).

There are no price controls on CO2. Its just that Afrox who supplies Coke and SAB had 2 of its major suppliers undergo routine maintenance shutdowns at the same time. More like poor planning by Afrox and coke.

I just read today in the local newspaper that a plant in my community is going to be producting 250 tons of purified (food and manufacturing grade) liquid CO2 daily as a by-product of another plant's ethanol production. Apparently the CO2 otherwise is just released.

Which makes me wonder, if that kind of CO2 is a by-product of ethanol production even before the ethanol is used (by burning), just how 'green' can ethanol possibly be? I suppose as long as it's not fossil it's a net gain. But it seems efficiency might be an issue.

Midwesterner:

You hit the nail on the head with the last sentence. A tremendous amount of energy is expended in converting sugary biomass to ethanol. The CO2 released for heating/boiling and then from fermentation is reclaimed in the next crop. (That is, if no fossil fuels are used for boiling.) So, from the perspective of emissions ethanol should be a net-C02 zero fuel.