Home charging an electric car in Stage 6 load-shedding is a breeze
It is entirely feasible to recharge an electric vehicle (EV) sufficiently in South Africa for commuting during the week, even under severe load-shedding.
That is according to a recent hands-on test of the Volvo XC40 Recharge Twin by MyBroadband over several weekdays.
Some EV sceptics have argued that owning an electric car is impractical because you would be unable to charge it sufficiently amid intensified levels of load-shedding.
What they fail to consider is that modern EVs can add several kilometres of range to their batteries within a relatively short period.
The Volvo XC40 Recharge supports up to 150kW DC fast charging and 22kW AC fast charging.
With the former, you can fill the battery from empty to full in about 40 minutes at the fastest public charging stations in South Africa, while the latter will take 3–4 hours.
While that might seem like a long time compared to a 2-minute petrol top-up, the typical EV charging regime differs greatly from refilling a petrol or diesel car.
Instead of only filling up when your tank drops below half or is close to empty, the best approach with an EV is to add a bit of charge whenever you have the opportunity.
The ideal time to do that is when your car sits in the garage or driveway while you are at home or sleeping.
While stage 6 load-shedding was in effect from 4 to 8 September 2023, I could take the XC40 Recharge Twin’s 75kWh battery from 55% to 100% in four days.
That was despite using the slowest charging possible — 2.3kW AC — and travelling regularly during the week.
My typical daily commute between our home and the office is 26–34km, depending on my route.
I generally leave at around 06:30 in the morning and return home just before 18:00, which means I often have over 12 hours when my car is not in use.
Over this period, the suburb where our home is located endured four hours of stage 6 power cuts on Monday and Tuesday, and six hours on Wednesday and Thursday.
The commutes to work and back depleted the battery by about 8–10% every day, and slightly more when we travelled on additional trips to the shops and a restaurant.
However, the 6–8 hours of charging time left were sufficient to top the battery up with over double its daily loss, resulting in a net gain of roughly 10% per day.
We found that the 2.3kW charging speed added over 10km of range per hour to the XC40’s battery pack.
The table below summarises how much charge I could add to the XC40 Recharge Twin each night of the week from 4 September 2023 to 7 September 2023 and how much potential charging time was lost to load-shedding.
Home charging Volvo XC40 Recharge Twin | ||||
Monday | Tuesday | Wednesday | Thursday | |
Charge level at end of day | 55% | 68% | 75% | 81% |
Charge level after overnight charging | 76% | 90% | 89% | 100% |
Estimated range added per charge (using an average consumption of 20.2kWh/100km) |
78km | 82km | 52km | 71km |
Actual charging time | 7 hours and 15 minutes | 8 hours and 20 minutes | 5 hours | 6 hours and 30 minutes |
Estimated kWh added using 2.3kW AC charging | 15.75kWh | 16.5kWh | 10.5kWh | 14.25kWh |
Charging time lost to stage 6 load-shedding | 4 hours | 4 hours | 6 hours | 6 hours |
Estimated potential kWh lost to load-shedding | 9.2kWh | 9.2kWh | 13.8kWh | 13.8kWh |
It should be noted that EV owners in South Africa typically get well over double our charging speed, as a dedicated 7kW or 11kW home charger is often part of the deal on new purchases.
Homes with three-phase power can get up to a 22kW AC charger.
That means even for the average South African motorist’s slightly longer return-trip commute of 44km, charging an EV at home will be no problem.
Another great advantage of using home charging to top up the XC40 Recharge was the significantly lower price of the required electricity compared to petrol.
My 115km of travelling from unplugging on Tuesday morning — after the first charging session — consumed roughly 23.25kWh.
On the prepaid Block 2 tariff in the City of Tshwane, that electricity costs R65.62.
Travelling the same 115km in my own Kia Sonet 1.5 LX CVT — a much less powerful and luxurious car — would have consumed roughly 7.19 litres of petrol.
That fuel would have cost me R164 if I filled up the same day I first charged the XC40 Recharge and consumed the typical 6.7km/100ℓ the car usually delivers on my commute.
The mild-hybrid petrol version of the XC40 — a more comparable model — would have required 8.41 litres costing about R192.
Both those calculations use the R22.83 price of unleaded 95 petrol before it shot up to R24.54 on 6 September 2023.