How do TOU and prepaid meters change EV charging (and solar export) in South Africa?

Answer first: Your meter type decides whether solar export and overnight EV charging are cheap, awkward or blocked. Self-use of PV into the wallbox still beats exporting at thin credits then buying grid later. Where you have true TOU off-peak, use it for night fills; where you are prepaid, budget for possible meter/tariff migration before hybrid export — especially under City Power.

Three meter stories that change EV maths

2026/27 export credits (primary-sourced) — why EV self-use wins

Full citations live on solar feed-in tariffs. Incl. ~15% VAT:

• Cape Town Home User SSEG — ~152.93 c/kWh incl. (107.98 feed-in + 25.00 incentive excl., then VAT)
• City Power (Johannesburg) residential embedded gen — 124.60 c excl. / ~143.29 c incl.; prepaid SSEG must migrate to TOU conventional; net-consumer; ≤1 MW; bi-directional meter
• City of Tshwane credit reverse — 94.13 c excl. / ~108.25 c incl. plus Domestic SSEG fixed ~R372.60/mo incl.; City FAQ may still show old 11.99 c — trust the NERSA RfD / your statement
• eThekwini residential net-billing — 160.52 c excl. / ~184.60 c incl.; network access ~R88.35/kVA/mo incl. of inverter; credits reduce the account (not cash)

Retail import is commonly ~R3.30–R4.70/kWh energy. Pushing PV into a Type 2 wallbox avoids the full retail rate; exporting then re-importing overnight destroys the spread.

City Power prepaid → TOU (Joburg edge case)

If you want registered export on City Power, plan the tariff migration into the project: residential exporters must sit on a time-of-use conventional tariff (ITEM-76 / Annexure A1 conditions). That changes fixed/service charges and how you schedule the EV. Do not assume your existing prepaid token meter will accept reverse power. Related: prepaid + solar.

Cape Town, Tshwane, eThekwini — EV scheduling notes

• Cape Town: Strong case for daytime solar charging; feed-in incentive helps leftovers but still below retail. AMI / Home User rules apply — verify on the City schedule linked from the feed-in page.
• Tshwane: Model the Domestic SSEG fixed line every month before you celebrate export cents. Confirm the live credit on your bidirectional statement (FAQ lag warning above).
• eThekwini: Oversize the inverter and you pay network access every month on kVA whether the EV needs it or not. Size continuous power for house + heat pump + wallbox carefully.

Practical wallbox settings

1. Solar-surplus or “eco” mode when you work from home.
2. TOU off-peak schedule when the car sits overnight and PV is gone.
3. Hard amperage cap shared with geyser/oven — load management.
4. Never park the EV on a small essential-loads battery bus.

Hardware starting point with local support: SAEV Charge — locally stocked option among peers we compare; Richmond public DC evidence ~R3.49/kWh vs GridCars ~R7.35 (DriveElectric).

Schedule the car to the tariff, not the other way round

Time-of-use and prepaid top-ups punish careless overnight charging on the wrong block. Before you buy a wallbox, screenshot your tariff name, peak windows and whether you are prepaid or conventional. Then set the charger app (or a simple timer) so the bulk of kWh lands in off-peak or in solar hours when the car is home.

On City Power’s residential exporter path, prepaid customers who want to export solar generally need a plan to move onto a conventional TOU meter — do not discover that after the SSEG form is in. Cape Town Home User / SSEG, Tshwane Domestic SSEG (export ~108.25 c/kWh incl. plus ~R373/mo fixed) and eThekwini (~184.60 c export incl. plus network access) each need their own spreadsheet; copy-paste between metros breaks the maths.

Worked overnight vs midday (illustrative)

50 kWh into the car each week ≈ 200 kWh/month. At ~R4.00/kWh peak retail that is ~R800. On Eskom’s Homeflex off-peak rate (about 253 c/kWh all-in incl. VAT in 2026/27, table below) the same energy costs about R506. Municipal TOU rates differ, so check your own schedule. If midday PV covers half of those kWh, you avoid retail entirely on that half and only “pay” the opportunity cost of not exporting at ~R1.08–R1.85/kWh — still a win versus buying peak power. Full export table: feed-in. Eskom Gen-offset detail: Homeflex solar export.

Eskom Homeflex 2026/27: the real TOU numbers for EV owners

For homes billed directly by Eskom, Homeflex is the residential time-of-use tariff, and it is the one solar homes connected to Eskom’s grid move on to. The table below adds the energy rate to the per-kWh legacy charge (28.50 c), network demand charge (32.98 c) and ancillary service charge (0.52 c) to give an all-in price per kWh. Figures are from Eskom’s 2026/27 Tariffs and Charges Booklet, including VAT.

All-in import = active energy + legacy + network demand + ancillary, incl. VAT, rounded. Fixed charges are extra: a Homeflex 1 supply adds about R6.60 + R15.17 + R1.25 a day (service/admin, network capacity, generation capacity), so roughly R700 a month. How Gen-offset credits work, the per-period export cap and the full Homeflex fixed-charge stack: Eskom Homeflex solar export.

What that means for a car: put 200 kWh a month into an EV (about 50 kWh a week, a typical commuter) and the grid cost works out to about R506 off-peak, R615 in low-season standard hours, R913 at low-season peak and as much as R1 818 at winter peak. Compare public DC: the same 200 kWh at SAEV Charge’s Richmond site (R3.49/kWh, reported by DriveElectric and MyBroadband) is about R698. At GridCars’ ~R7.35/kWh it is about R1 470. Off-peak home charging is cheapest, rooftop solar in daylight is cheaper still, and a winter-evening plug-in on Homeflex is the costliest way to fill up.

Watch the new hours. Eskom’s 2026/27 booklet notes that the TOU windows changed: the evening peak grew from two to three hours, the morning peak shrank from three to two hours, and Sunday evening gained a new two-hour standard period. If you set your wallbox timer before April 2026, check it against the current Eskom TOU chart. An old schedule could now start charging inside the expensive evening peak.

Municipal customers: City Power, Cape Town, Tshwane and eThekwini set their own TOU and block tariffs, so the Eskom table above is a reference point, not your bill. Find your tariff name on the bill and use the matching metro schedule on our metro tariffs hub.

Prepaid practicalities

• Keep a top-up buffer; a long charge session should not zero the meter mid-evening.
• Some prepaid STS meters and EV loads interact badly with aggressive load-limiting — test a short session before the first road trip night.
• If you add solar later, ask upfront whether your prepaid meter type can stay or must migrate.

Wallbox settings that match SA homes

Prefer a charger with scheduling, a solar-surplus mode (CT or inverter integration) and a hard amperage cap so you can drop to 10–16 A when the DB is busy. Pair with load management so Stage evenings do not fight the kettle and geyser. Public DC remains for trips — networks.

Related answers

• Feed-in / net billing 2026/27
• Prepaid meter + solar
• Cost to charge an EV
• Electricity tariffs 2026
• Heat pump + solar + EV
• Metro tariffs hub

Sources

• City of Cape Town 2026/27 Budget Annexure 6
• City Power Annexure A1 Embedded Generator Tariff 2026/27
• NERSA RfDs: City Power, City of Tshwane (SSEG 17.14), eThekwini Residential Net-Billing — linked from the feed-in answer
• DriveElectric / MyBroadband — SAEV Richmond tariffs, Oct 2026
• Podium Energy: Eskom 2026/27 rates (grid-tied solar on Eskom supply moves to Homeflex)
• Eskom Tariffs and Charges Booklet 2026/27: Homeflex and Gen-offset Homeflex (non-local authority), TOU hour changes