Eskom Homeflex makes charging an EV over 70% cheaper than using petrol

[Jan]

This Eskom tariff makes electric car charging over 70% cheaper than using petrol

Using Eskom's recently-introduced time-of-use tariff, EV owners could save around 70% in transport costs compared to using a similar petrol-powered model, an analysis by MyBroadband shows.

First made available in April 2023, the Homeflex tariff plan's charges change based on the typical demand Eskom experiences throughout the day.

 

[G.A.S]

Random thoughts-

1. Unfortunately the Homeflex time-of-use option isn't available to everyone
2. Unfortunately you cannot resell back to the grid at the time-of-use tariffs and recharge at lower tariffs later
3. Unfortunately the grid will collapse if you replace all petrol and diesel vehicles with EVs right now.

 

[DapperDanMan]

Unfortunately the grid will collapse

At least you're in the right business for when that happens!

 

[Priapus]

Random thoughts-

1. Unfortunately the Homeflex time-of-use option isn't available to everyone
2. Unfortunately you cannot resell back to the grid at the time-of-use tariffs and recharge at lower tariffs later
3. Unfortunately the grid will collapse if you replace all petrol and diesel vehicles with EVs right now.

Very much doubt.

 

[wingnut771]

Eskom Direct households with a regular single-phase 16-amp connection to the grid will be placed on the Homeflex 4 plan if they choose to switch from Homepower 4.

Good luck running a whole house and charging an EV with 16amps.

 

[Next Thing]

Now , how about a price comparison between the petrol and ev cars and show how that difference is going to be made
Also the type of homes that will be targetted for homeflex are the not the people in the income bracket who will be buying EV's imo ...
Half arsed and badly researched article

I also see the additional charges not being accounted for

XC40 - Electric - 1.108Mil
XC40 - Milk Gybrid - 700k

That is a ton of KM's to do to make Up R400k price difference
You wont be buying an electric purely to save money :/

 

[G.A.S]

Very much doubt.

In 2022, SA imported -

• 6 bn liters of crude oil
  • let's assume 45% of this goes to petrol and
  • 29% goes to diesel
  • the remainder goes into other products
• 12 bn liters of diesel
  • In 2022/04 to 2023/03 Eskom used 0.94 bn liters of this
• 5.5bn liters of petrol

For the sake of argument, let's ignore diesel and petrol used to run generators, as it would be pointless to convert to EV without first fixing that problem.

Note that I haven't included petrol and diesel manufactured by SASOL in the above either.

Diesel has an energy density of ~36.9MJ per liter and petrol has an energy density of ~33.7MJ per liter. Let's assume again efficiency of 50% for Diesel and 36% for Petrol (this is on the high side). 1MJ = 0.27...kWh

So in order to convert this to kWh "at grid" (i.e. assuming electric vehicles are 100% efficient grid-to-road, which they are not):

• ( 6,000,000,000 * 45% + 5,500,000,00 ) * 33.7 * 0.277777778 = 30,423,611,135 kWh = 30.4 TWh for petrol. At 36% efficiency, this is 10.9TWh.
• ( 6,000,000,000 * 29% + 12,000,000,000 - 937,508,149 ) * 36.9 * 0.277777778 = 131,225,541,577 kWh = 131.2 TWh for diesel. At 50% efficiency, this is 65.6 TWh

In 2023, Eskom generated about 218 TWh (this is before transmission and other losses. I'm fairly sure another 35% consumption will collapse the grid, since this demand cannot be reduced by loadshedding (remember I said "right now"?).

 

[Priapus]

In 2022, SA imported -

• 6 bn liters of crude oil
  • let's assume 45% of this goes to petrol and
  • 29% goes to diesel
  • the remainder goes into other products
• 12 bn liters of diesel
  • In 2022/04 to 2023/03 Eskom used 0.94 bn liters of this
• 5.5bn liters of petrol

For the sake of argument, let's ignore diesel and petrol used to run generators, as it would be pointless to convert to EV without first fixing that problem.

Diesel has an energy density of ~36.9MJ per liter and petrol has an energy density of ~33.7MJ per liter. Let's assume again efficiency of 50% for Diesel and 36% for Petrol (this is on the high side). 1MJ = 0.27...kWh

So in order to convert this to kWh "at grid".

• ( 6,000,000,000 * 45% + 5,500,000,00 ) * 33.7 * 0.277777778 = 30,423,611,135 kWh = 30.4 TWh for petrol. At 36% efficiency, this is 10.9TWh.
• ( 6,000,000,000 * 29% + 12,000,000,000 - 937,508,149 ) * 36.9 * 0.277777778 = 131,225,541,577 kWh = 131.2 TWh for diesel. At 50% efficiency, this is 65.6 TWh

In 2023, Eskom generated about 218 TWh (this is before transmission and other losses. I'm fairly sure another 35% consumption _will_ collapse the grid (remember I said "right now"?).

Again, I reiterate. It will not collapse the grid. We already have a power deficit, which is why load shedding exists. A bigger deficit will just mean more load shedding. But no grid collapse.

 

[porchrat]

Random thoughts-

1. Unfortunately the Homeflex time-of-use option isn't available to everyone

Indeed

1. Unfortunately you cannot resell back to the grid at the time-of-use tariffs and recharge at lower tariffs later

No reasonable person would expect to be able to resell back to the grid at the same rate charged for that power.

You will always get a fraction of what they charge it out at.

1. Unfortunately the grid will collapse if you replace all petrol and diesel vehicles with EVs right now.

Won't happen anytime soon. EVs far too expensive.

 

[Next Thing]

Won't happen anytime soon. EVs far too expensive.

Reason I said is buying an EV is not to same money

 

[G.A.S]

Again, I reiterate. It will not collapse the grid. We already have a power deficit, which is why load shedding exists. A bigger deficit will just mean more load shedding. But no grid collapse.

Loadshedding won't affect EV recharging ... they will just recharge when the power comes back on...

Also, "only" 16TWh was shed in 2023. This demand is several times that.

Or put another way, this works out at at least 8,732MW* additional demand around the clock which cannot be negated with loadshedding.

* ( 10.9TWh + 65.6TWh ) * 1,000,000 / 365 / 24

 

[Nerfherder]

Indeed


No reasonable person would expect to be able to resell back to the grid at the same rate charged for that power.

You will always get a fraction of what they charge it out at.

What is expected is that when its peak hours you can sell back at a higher rate than off peak.

There will always be a massive discrepancy, such that you won't be able to charge during off peak and sell back during peak.

 

[G.A.S]

What is expected is that when its peak hours you can sell back at a higher rate than off peak.

There will always be a massive discrepancy, such that you won't be able to charge during off peak and sell back during peak.

TBH though, there would be a lot of sense in getting rid of that discrepancy from a grid point-of-view, since peaking-power production is pretty expensive.*

The buy-back rate just needs to be cheaper than peaking-power in order to make sense.

*Assuming that the grid doesn't use peaking-power 24/7 as Eskom is currently doing...

 

[Nerfherder]

Reason I said is buying an EV is not to same money

The gap is narrowing though.

ICE cars are getting expensive and require maintenance. EV's are getting cheaper and have very few serviceable parts.
(Cheapest EV is R600k now, decent ICE car is R350k-R400k)
Everyone is getting solar anyway so not an extra cost for many. Base price of electricity is going up and up, so feeding back (and selling) is becoming a good option.

Feeding back during the day could offset night time charging.
In a world where you have to a lot of driving during the day and are not at home using power, its becoming the cheaper option. I think that time is soon.
Perhaps not for everyone though.

 

[Nerfherder]

TBH though, there would be a lot of sense in getting rid of that discrepancy from a grid point-of-view, since peaking-power production is pretty expensive.*

The buy-back rate just needs to be cheaper than peaking-power in order to make sense.

*Assuming that the grid doesn't use peaking-power 24/7 as Eskom is currently doing...

Yes, it could work in that every household would act as a battery for peak time. The issue though is they need to make sure they make a profit. If the customers make a profit then the entire system falls apart.

or fixes the entire supply problem... who knows.

 

[Priapus]

Loadshedding won't affect EV recharging ... they will just recharge when the power comes back on...

Also, "only" 16TWh was shed in 2023. This demand is several times that.

Or put another way, this works out at at least 8,732MW* additional demand around the clock which cannot be negated with loadshedding.

* ( 10.9TWh + 65.6TWh ) * 1,000,000 / 365 / 24

You’re missing the point. For the grid to collapse; it means Eskom would have done nothing when power demand exceeded supply and then power stations would trip causing a collapse.

That won’t happen. Eskom will just cut demand.

 

[DreamKing]

...... however, 70% is not working.

 

[Mannydefreitas]

Very much doubt.

There is not a country on earth that could handle an overnight change to 100% EVs, even Japan's grid couldn't handle it.

But you think SA can?

 

[Skerminkel]

Lots of commenters here trying to show how smart they are...
It is a valuable article, thanks Hanno and Jan.

 

[Priapus]

There is not a country on earth that could handle an overnight change to 100% EVs, even Japan's grid couldn't handle it.

But you think SA can?

Sigh, I said I doubt the grid will collapse. I didn't say it can handle it. Eskom will just deepen the power cuts. A grid collapse means something completely different.