One thing I’ve continually had to refute is whether we could support EV’s on Eskom’s grid in South Africa.
Yes, even with our current load shedding woes, it won’t be an issue, has long been my answer.
So, with that in mind, let’s put my money where my mouth is, and do some basic math to prove this.
I’ll start – let’s hand wave, and convert 500,000 cars to EV.
500,000 EV’s – woohoo! Go SA.
To work out how much extra power is going to be needed by Eskom, we first need to work out a few things. Assumptions are a good thing to start with, so let’s make some of those..
As I’ve stated previously (and if you look at some of my previous posts, referenced with data), the average car journey in SA is 40km/day. Let’s use that as our first assumption.
Next up, lets look at efficiency;
We will be using SI units below for simplicity.
SI units are the standard units of measurement defined by the International System of Units (SI)
kW – refers to instantaneous power.
kW.h – refers to energy used.
eg – a 2kW kettle would use 2kW.h if left on for an hour, or 1kW.h if left on for 30minutes.
EV Batteries are typically measured in how many hours of storage capacity/ energy they contain.
eg a BMW i3 may have between 18kW.h – 42kW.h of battery depending on model, and use 16kW.h to travel 100km, which gives the latest models roughly 250km of range.
My personal bare minimum recommendation for SA would be a car with 40kW.h of storage capacity.
What’s the efficiency of an average EV?
The average efficiency for EV’s is 20kW.h / 100km. Some are higher, some are lower, hence “average”.
Using that average figure of 20kW.h / 100km consumption (the amount of energy consumed by an EV for a distance travelled), and our average travel distance in South Africa (40km/day travelled), we’ll need 8kW.h of energy daily to recharge our average EV.
Most EV’s are well under that 20kW.h / 100km figure. – eg the Mini Cooper SE (which is available in SA) is 15.6kW.h/100km
There is a nice graph here with per car efficiency figures for pretty much any EV vehicle ever made –
Well worth looking through if you want to buy an EV.
If we concentrate on the rather limited models of EV’s available in SA – the most efficient EV in SA uses roughly 15kW.h/100KM (Mini Cooper), the worst – eg the Jaguar Pace (22.3kW.h/100km), and Mercedes EQV (27kW.h/100km !).
In gas terms – the Mini Cooper is lowish, the Pace high, and the EQV – well, I wouldn’t want to own one.
Next – how are we powering our EV? For that, lets look at the average connection in a garage.
What’s the connection in an average home?
Your average garage 20a plug can support roughly 3.6kW of power draw over an extended period of time (assuming a 2.5mm cable, and a few hours of charging needed).
Assuming a 20a cable supplying 3kW per hour we’ll need a little over 2.5 hours (2hrs 40min actually!) to charge our average car (assuming 8kW.h required at 3kW per hour).
Let’s bump that up again for a bit more margin and allow for 20% for losses into the car and call it 10kW.h of power needed for each car overnight.
This comes to 3hrs 20mins needed to recharge our average EV. Let’s round that up again to 3 1/2 hours or 3hrs and 30 minutes.
How about Eskom?
We have 500,000 EV’s to charge at 3kw per hour so we’ll need = 1,500,000kW.h
1GW = 1,000,000 kW, so we’d need Eskom to be able to supply 1.5GW.h of additional energy for a number of hours.
Given that basic math, we’d need 1.5GW.h additional load for 3 1/2 hr’s overnight, including any losses in transmission as I’ve calculated in plenty of excess into our figures.
Ok, now we now whats required, let’s look at the current situation.
This is a snapshot of a typical week in November for South Africa showing daily usage for electricity.
If we look at the daytime, you can see the duck curve – we have a rising morning load, then daytime dips (quite likely due to solar), and then rising sharply for our evening peak – which is quite pronounced!.
You can also see where industrial load (contracted demand) has likely been dropped (or load shed in Eskom parlance) as demand is > supply on the 7th, 8th and 12th.
After that evening duck curve spike in the 6-9pm range, our late night, overnight demand drops radically to use roughly 2/3’s of our available supply, this gives us a nice figure of roughly 10GW available at any point overnight.
Eskom would be happy to supply that too, as they make money selling electricity. Allegedly, cough.
In raw numbers, our Peak capacity is around 28-31GW for that week. Lows are in the 20-22GW range.
While we in theory only need 1.5GW.h, even if we upped that requirement to 2GW.h during the lows (i.e. overnight), it would still be no problem for Eskom to supply. You could bring the lower line up to 27GW without issues as generation is consistently over that, which would give us even more headroom.
In conclusion – the grid as it stands can definitely supply an extra 2GW.h of power for 4hrs overnight each night.
It can do that for around 10hrs looking at the stats, so immediately adding 500,000 EV’s in South Africa even with load shedding would be no issue whatsoever. Adding 1 million EV’s would also be fine. That may take a few decades though 🙂
Just in case we still have some non-believers – I’ve put far more excess and rounding upward than would be needed in reality into the figures, and its still no issue.
One caveat – The cars couldn’t all be charged at 6-9pm, as we do not have sufficient power at that specific time period.
That one is a quite easy solution to solve though, and one that is already implemented in other countries.
Charging different rates at different times. Time of Day pricing would push charging to times when electricity is cheaper – eg overnight when our usage is lowest.
In a time of day pricing economy – car owners will have the easy choice of charge now at 3 or 4 times the rate, or charge at 11pm onward at cheaper rates. Most would choose the cheaper option!
So, in conclusion, despite all the naysayers alleging we wouldn’t be able to power EV’s, we can, and it’s doable even now.
Our next issue contentious issue is vehicle pricing!
That’s however, is a whole other topic to cover.
My short answer to this is while cheaper EV’s exist, we won’t get them till we lose the taxes; or have some local EV builds.
Current car taxes in SA effectively promote smaller engine cars over EV’s. EV’s are hit with 2 separate taxes – a luxury tax, as pricing is higher, and a specific EV tax. These taxes effectively bring the rate for a landed EV to 160% over landed costs in volume. In small volumes, this is even higher, as additional taxes are imposed.
If you’re looking to bring in say, a Tesla, you’re looking at around 190% total cost.
i.e a £30,000 ($40,000 USD) electric car will cost a minimum of 1.1million randela’s (our local currency).
Side Note – I’ve used UK car pricing above, as South Africa is RHD (Right Hand Drive), and that Tesla EV will most likely be sourced from that specific export market. Longer term we’ll see RHD EV’s coming from Asia, but thats still a year or three from fruition for a number of reasons. I don’t want to delve into into too much detail here other than to note battery availability is a big one, and most large scale battery manufacturer’s are at capacity already, even if they’re ramping up rapidly.
Yes, there are other car markets that ship to SA; Germany in particular, but most German EV’s are gimped – BMW and Mercedes I’m looking at you in particular. I have owned or own several of both marks, and personally would like them to hurry up a bit on things. Grumble tiny undersized battery Mini grumble grumble.
The other big German mark’s are VW and Audi. Fondly known as VAG for some reason (Volkwagen Audi Group). VW is the undisputed king of announcing EV’s, but rather less of those have actually become available in our hemisphere.
Audi – in my book, you’re doing well, although I’d like to see some lower end options, even if I would totes covet an RS E-Tron. I won’t go into the other mark’s, other than a cursory hand wave to Porsche who are also doing good things in the EV space.
Pivoting back to the discussion, those additional taxes reflect in our sales numbers – Total EV sales in 2020 were a staggeringly low 92 vehicles.
(2020 numbers referenced from here – https://african.business/2021/09/technology-information/opportunities-for-africa-in-electric-vehicle-market/ ).
The midyear KZN violence in 2020 also hasn’t helped with enticing new (or old) car companies to invest in building EV’s in SA. That, and we don’t have a local car industry. It’s literally all multinationals.
Status quo for the multinationals is likely keep most pricing as it is for as long as possible, until they are forced to change by our government (or more likely, pressure on our government from international lenders). There is some push to reducing EV taxes, but our government is scared of losing the petrol tax, so they’re pushing that forward as much as possible.
My suspicion is that the longer the we stay EV unfriendly, the better it will become for multinationals, so while there will be some lip service to reducing costs, longer term it benefits them to have a semi captive African market to sell petrol/diesel cars into, especially as foreign first world sales will be steadily decreasing.
This can be seen with our white goods market where Africa gets dumped the older less efficient products which cannot be sold in 1st world countries. I expect this to play out in a similar manner for cars.
We will probably see some mild investment in EV manufacturing in the short to medium term, albeit mostly for export cars, but again, I suspect that the multinational companies will be happier with the status quo.
Let’s put it this way – If we put all of our current EV’s on the grid at peak time (somewhere in the region of under 1,000 vehicles), Eskom wouldn’t even notice the extra load.
Eskom on the other hand will be more concerned about 7de Laan, as the ouma’s turning on their kettles at the end of an episode will have more of an impact on the grid.
Last but by no means least lets dip into efficiency –
Electric cars are far more efficient, your average Electric car “uses” the equivalent of 2L of petrol for 100km.
(1L petrol is roughly equivalent to 9.8kW.h of energy)
Even the hideously inefficient Mercedes EQV “uses” around 2.6L of petrol for 100km.
Electric cars will always be cheaper to run than petrol or diesel engine cars.
The other bonus is that it’s easy and cheap to add an electric generation plant at home.
Try doing that for petrol (or diesel)! 🙂
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