And further, when we look at SA usable, again we fall way lower down….
OmgevaldeGroetnis
You are saying that you haven’t been able to charge your battery without ESKOM.
It’s not that your batteries have been “pretty useless”, but your PV generation during recent inclement weather has been “pretty useless”.
This is an important distinction not to be conflated.
I actually suspect your batteries have been very useful to you during this period.
Separate the generation ( renewable or otherwise) from the power storage.
A pumped storage scheme is just a big battery that can suck up excess power at one time and deploy it at a later time. Eskom uses Eskom’s power to do this, and it is part of their strategy.
The point is domestic users collectively create the equivalent of another massive battery deployed as a peaking plant.
Using ESKOM base generation to charge it is still helpful because that is precisely what Eskom does.
That is bonus number 1 for ESKOM.
Bonus 2 is the fact that you can sometimes charge that with alternative renewable generation.
ESKOM doesn’t have the renewable generation capacity to do that like a domestic user but wishes it could.
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Your battery is to small I would venture 
All joking aside, I really have no idea about your system size or use case at all.
Sometimes, infrequently over a year, I use some utility to supplement as well, almost exclusively during the winter months, due to space heating. If it was not for that, my system would be off grid.
My battery bank at 40kWh is still to small, need to get to 48kWh. My solar is 12.6kWp and I can deliver 10.2kW at peak Sun, Winter and Summer. Summer time obviously over a much longer time period. But then, I designed it specifically to produce enough during Winter to charge me batteries from flat to full in a normal sun Winters day. Rainey weather kills it.
HelderGroetnis
We can dream 
But serious with TOU and Feedin Sorted we could use Eskom as our battery and not have a BIIIGGG battery like YOOUURRSSS!
To go off-grid, absolutely not at 17kWh.
Take your example, 45kWh “still too small, need more” … that was/is where do I draw my line.
When doing the sums way back, the ROI was the key for me, linked to equipment life expectancy, at which point I will have to pay upfront the Eskom use again. I worked on wife and I and ids moving out, and my parents.
Then the house arrangements changed completely. More humans moved back. Can my wife and I get buy close as damn to near off-grid in Cpt summer? Damn close yes.
What put me off, especially living Cpt weather since 2012, winter.
As I posted, the 5.2kw array, 165w due to clouds max. No matter how many panels I put up, on these days, weeks now, I can basically forget it. I’m happy to use Eskom on these days. As bigger sums don’t make sense to me.
TTT that was tongue in cheek man.
The reason for me to go solar was 2 fold.
Firstly it was to stop giving the mafia any more money to get Net Zero in return.
Secondly it was due to being on the inside. I saw what I saw. I worked on the first load shedding software project. I was designing and helping to build and the deploying the Distribution SCADA system that controls the distribution grid, a good 70% of what Eskom does.
It took me a while to scheme things through, then to learn and then to do many iterations of planning, designing, learning new modelling software, modelling systems and understanding the basics. What I posted on my system was not the first iteration, but the last. There were many ten’s of versions, likely closer to 100, before I was happy.
Not to rehash, but ROI was low down the order of priorities. No I am not rich, not by any stretch of the imagination. Then I had to save up, took me a good few years. In the meantime I was still paying the mafia, it irked me no end.
I wanted to get away from all the Eksdom crap, only was is to effectively be off grid. most there. One thing, like speaking English only in self defence, was I had only one go at this. So today, as designed is as build, apart from 2 more battery modules to take me to 48kWh.
Only done one upgrade this far, adding the 3rd tower and two packs (8kWh) but that was planned and so are the next two. The busbar, battery cables (3 sets) and the main battery BMS controller interface was done on day one.
I am so glad I had this done and completed 2 years ago. Saved me a lot of hassle, money both on equipment and on the bill side. The power of independence of a bunch of mafiosi and pillocks in government and eksdom does, is liberating to say the least. Saw the writing on the wall. With power and water they cannot control me. Tough said…
OnafhanklikeGroetnis
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I know, I also reply to others reading the same post, better context.
What you also said … my system may not be my last iteration. It does get “easier”, and the finances, if one can wait for the dips (price drops), one can score a lot. VS being forced to buy.
Me, I’m hedging my bets on where CoCT is going … as Eskom is a lost case in the current situation.
The estimate is in essence for the peak production of the total installed capacity. This output will only be theoretically reached for a period around midday (and assuming the whole of South Africa has a perfectly cloudless day). From the same article there is an indication that much larger, and one would think more optimally designed, commercial scale PV plants the output was more than 50% for only around 50% of the available sun light hours in a week and reached production above 70% for only three hours in total (granted it could have been a bad week but the capacity factor for these types of plants are quoted around 30%).
So, it highly unlikely that 4000MW of PV would have been able to reduce close to 4 stages of loadshedding.
The reduced load though does help, and according to Mr Eberhard this is likely most useful in freeing up energy to restock pumped hydro and diesel reserves.
As far as batteries go, the estimate as per the article, is not only residential PV but include the big PV installations on malls etc. I do not have numbers but will bet that a very big proportion of those instalations do not have much battery backup. Even a very big proportion of the residential PV market I think probably do not have battery that effectively removes them from the grid especially during the evening peaks - how many people still have essential/non-essential splits? The loads generally kept away from batteries are exactly the big loads. So, while every bit helps I think the contribution is not yet as big as we might hope.
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I would venture a guesstimate that 20-25% reduction happen, ie 1000 to 1500MW overall from the 4400MW peak generating capacity. This is based on no facts at all. 
The real point is half of this was just added just this year. As private citizens, we are again outperforming the so called (by me) professionals by far. Take the Rupert plant, not allowed to supply surplus power, nope we don’t want that. Somdear South African, get off yer lazy arse, make your own power en be free, there, I said it 
VryburgerGroetnis
Its quite interesting, my system is much smaller than yours is, but I have exactly the same ratio of battery to PV 10.7kWh of storage and 2.4kWp on the roof, and even now in Winter (if the weather plays along!) with my minimum SOC at 60% I still manage to get the batts fully charged by 13:00 
I often see these prepacked systems: 5kW inverter + 5kWh battery + 4kWp of panels and think:
Where are you going to put all that PV?
Maybe other people have different demand curves, but there is almost nothing going on at my house during the day. (I use less than 600kWh a month with no gas appliances)
Believe you me, I am envious now…. The best way to spend yer money on solar, is to not consume it in the first place. I keep on telling myself, to no avail.
Everything is essential to me, well err no, to the wife and daughter, hehehe. I guess I am now redundant. I had a few years worth of consumption records in prep for my design, so was prepared. Could base my design on 5 years worth of consumption patterns.
The ratio of solar to storage is quite important. I was shooting for Winter period to charge 48kWh on an ok day before 16:00, that got me this ratio.
OpgecgargedeGroetnis
looking at Eskom load data for 18:00ish compared to 11:00-13:00ish the 1000-1500MW seem quite feasible.
The comparison of residential and commercial PV to REIPPP is bit of an over simplification. Even if forgetting about the grid constraints (yes, it should have been worked at long time ago) the utility scale projects are very different from sticking some panels on a roof. These projects typically span years from inception to production.
It might also be interesting to know how much of the increase in PV attributed to this year is purely an indication of people being desperate/fed-up/not seeing any electricity resolution/getting of their arse versus the lifting of licensing requirements etc. that started making the viability of bigger PV plants more attractive.
I don’t think there is enough publicly available information about what the existing state of the L’Ormarins hydro plant is and/or why it might be. That dailyinvestor “article” is based on 3 year old information with no real attempt at getting updated information.
Requests for information from the estate manager should be much more likely to produce information than asking Rupert I think. So, whoever goes through the trouble of obtaining the information should please post it, so we know. The engineers indicate the plant being commissioned only by 2018 - so it could not have been connected to the grid for three years by 2019.
The hydro plant in question is also purely a commercial decision (reducing production costs by banking energy credit for use when tariffs are higher and also having green credentials for the export market) so “giving away” any excess is unlikely. If no new PPA has been concluded since then it might be more complex than just a one sided “Eskom does not want it”.
The actual surplus from the plant is also not clear. The 2019 info refer to a 2MW potential surplus under ideal conditions. On the WWF site with a membership dating from September 2020 it is indicated that only 20% of the farm/estate energy generation is “green”.
OCGT use related
While Eskom’s diesel spend is indeed within its forecast budget of R12.44-billion for 1 April to 31 July 2023, it had already spent R12.42-billion as of 24 July. This means the utility will need to keep its diesel purchases under R26.3-million (the difference between the forecast budget and the expenditure so far) until 31 July to remain within budget.
With seven months remaining in the current financial year, electrical engineer and energy analyst Chris Yelland said it was unlikely that Eskom would not exceed its diesel budget.
Yelland told Daily Maverick, “At the current rate of usage, and the current load factor at which the OCGTs are currently running, I expect the diesel spend to be about R36-billion.”
The only thing that might prevent Eskom from approaching the National Treasury with a begging bowl is if it improves its generation capacity. This could be a challenge if delays in returning Unit 1 at Koeberg Power Station to service continue
The point I am making is missed altogether. It’s not technical at all. In broad strokes the technical details are fuzzy at best, I agree.
The issue is the lack of market anticipation, planning and an understanding, by Eksdom. That is because whomever guides that business, have not a cooking clue. Ideology for them trumps everything, the lack of vision is stark. Like them bid windows, what’s the point if there is no connection capacity? Do they even know what capacity for connection to the grid they have, I doubt highly if they have real hard data? Even if they do, the internal comms suck so bad (ask me, I know from experience) that the true capacity will not reach whomever needs to make a decision…
Another point is many more smaller projects are quicker to complete, can be run in parallel and connected with lesser capacity connections and be more distributed. They may also be situated closer to the current Transmission lines, but more importantly, can be connected to Distribution lines, and that part will be a sea change. But no…
Further it has proven out over time that Eksdom cannot keep up with the speed of change required, kind of a dinosaur, let alone keep up with private sector.
Groetnis
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Goes right back to this thread: Eskom … is their ANY chance?
Answer: No.
Main reason:
If the data is there, but no skills, lack of management backing/drive, and/or funds … you have a dinosaur.
Think this is where we get into so many interesting debates. The individual facts surface, we can debate it, reason it, and make sense of it.
But the core matter in the big picture for SA, some author’s freedom to illustrate… “Mantashe is not in the same room” as the rest of SA.
That Rupert story is also a really really old one. I’ve read it the first time years ago. Because I’m in my middle ages, I cannot even tell you how many years ago… because everything is starting to feel like it was only yesterday. But it is definitely a story from yesterday helpfully dug up by a journalist, without any of the details as to WHY it is so hard to connect a random water turbine on a farm outside Franschoek to the grid.
It’s actually an extremely nice place to visit on the weekend. They have an awesome car museum there too. But in terms of grid connectivity, or what you’re going to do with it, it is somewhat limited.
Another one speaks up … publicly.
Then this gem at the end … WTF!!! He worked there for decades and this “never came up”!!! Ties right back to my previous post …
Oberholzer said he would love to use his skills and experience to assist Eskom with procuring additional capacity.
Been to the Car museum a few times, very nice place indeed.
That is just the ting on the Transmission grid, no vision coupled to the green dive to know you need more capacity in the Western parts… jaaaa boet.
Also why the smaller plant, wind, solar, battery systems would be, or could be, a huge boost. They can connect to distribution grid, be dispersed over a much larger area and also help negate some local weather. Much quicker to deliver and get online. But like that will most likely never happen, because it’s os not transmission. let me tell you something, Transmission and Distribution hate each other even more than Generation hates them both…
Groetnis