Yeah all that batteries do is time-shift power usage. If there's an overall shortfall of power generation, batteries don't really help on a systemic level.

And every little business having its own diesel generator is just like building more power stations, but much dirtier and less efficient...

Exactly. I've had conversations with friends about how much less effective load shedding must be now compared to when it started because of the proliferation of battery backup. At the beginning, an two hour cut would have reduced total GWh used substantially. But now, as soon as the cut ends demand will spike as batteries charge. Without data on just how many batteries there are it's hard to work out at what point an additional hours cut will be required!

Of course it's not the biggest crisis because grid-level electricity usage spikes overwhelmingly at morning and evening peaks. So if you can use the power cut schedules to shift demand away from these peaks, even if the batteries reduce the efficiency a bit, you're still having a substantial effect on the required peak grid power.

The problem is that not everyone can afford battery backup, due to the poverty in our society the country basically has to have a reliable base load. Coming from the sections of society where everyone has solar, inverters, datacenter style lipo UPS in their houses etc. it's also been interesting to me how inefficient storage at the endpoint is. People are spending R300k ($17k) on batteries and inverters sized to their houses' peak load, but 90% of the time they could actually get by with radically less. I read on HN about a company making a smart Distribution Board for houses - seemed like a really good idea based on this. If you can intelligently manage load you can cut your off grid setup cost substantially at minimal inconvenience.

This whole thing sounds like an astounding market failure. Many can buy their way around society's inability to deliver (even quasi-) reliable electricity, but just wow.