EV & solar
What does an EV add to a South African electricity bill — and how much does solar take back?
An EV driving 1 500 km a month adds about 264 kWh to the meter. In Cape Town that is about R1 238 a month on the Home User top block, lifting a typical 800 kWh household from about R3 498 to R4 736. Solar and a battery that cover the house’s daytime load plus most of the car’s charging cut that combined bill to about R2 050 — against roughly R6 860 for the same household running a petrol car that uses 7.4 litres per 100 km at R30.25 a litre.
Updated 27 October 2026 · Worked examples use published tariffs; not a formal quote, credit decision or financial advice.
Answer first: An EV is the single biggest load most South African households will add this decade, and it lands on the most expensive part of an inclining-block bill. That is exactly why solar and EVs belong together: every kWh the roof puts into the car saves the top-block price, and the battery moves midday solar into the evening when the car is home. Related: charging an EV from solar · cost to charge an EV · EV charging guide.
Step one: how many kWh the car adds
A compact EV driven 1 500 km a month at 16 kWh per 100 km uses 240 kWh at the battery. Home AC charging loses roughly a tenth on the way from the meter to the cells, so plan on about 264 kWh a month at the meter. Swap in your own car’s trip-computer figure and your own monthly kilometres; the method stays the same.
Step two: what those kWh cost on the grid in 2026/27
On inclining-block tariffs the EV’s kWh land on top of the household’s existing use, so they are billed at the top block.
| Where you charge | Price per kWh (incl. VAT) | 1 500 km a month |
|---|---|---|
| Cape Town Home User, above 600 kWh | 469.06 c | ≈R1 238 (264 kWh) |
| Tshwane, above 650 kWh | 445.51 c | ≈R1 176 (264 kWh) |
| City Power prepaid, above 500 kWh | 436.59 c | ≈R1 153 (264 kWh) |
| SAEV Richmond Park DC, battery >90% SoC | R2.49 | ≈R598 (240 kWh) |
| SAEV Richmond Park DC, standard | R3.49 | ≈R838 (240 kWh) |
| GridCars DC | ≈R7.35 | ≈R1 764 (240 kWh) |
| Own midday solar (Cape Town export credit forgone) | ≈152.93 c | ≈R404 (264 kWh) |
Sources: City of Cape Town 2026/27 tariff Annexure 6; City of Tshwane tariff notice; City of Johannesburg 2026/27 electricity tariffs; DriveElectric (October 2026); SAEV Charge. Public DC is billed at the charger, so we price 240 kWh there. Tshwane’s blocks are shown as the city publishes them. SAEV’s Richmond Park site sits at Solar MD’s factory and runs on a battery energy storage system, which is why it drops to R2.49/kWh when that battery is above 90% — the cheapest published public DC price in the country and the reason many drivers choose it for speed and price together. See our Richmond Park report and cheapest public DC.
Step three: the combined bill, Cape Town worked example
Cape Town’s own example shows a Home User household using 800 kWh a month paying about R3 498 incl. VAT: R424.30 service and wires charge, 600 kWh at 355.95 c and 200 kWh at 469.06 c (City of Cape Town cost-of-electricity page). Add the EV and compare three set-ups:
| Set-up | Grid kWh | Electricity bill | Fuel | Monthly total |
|---|---|---|---|---|
| Petrol car, no solar | 800 | ≈R3 498 | ≈R3 358 | ≈R6 856 |
| EV, no solar | 1 064 | ≈R4 736 | — | ≈R4 736 |
| EV + solar and battery covering 608 kWh | 456 | ≈R2 047 | — | ≈R2 047 |
The petrol line uses MyBroadband’s October 2026 comparison figures of 7.4 litres per 100 km at R30.25 a litre (MyBroadband (October 2026)): 111 litres for 1 500 km. The solar line assumes the system delivers 450 kWh a month into the house and 158 kWh into the car — about 20 kWh of self-used solar a day — leaving 456 kWh from the grid, all inside the cheaper 355.95 c block. The arithmetic is ours; the tariffs and fuel figures are the published ones.
The swing is large: about R4 800 a month between a petrol household without solar and an EV household with solar. Even the EV-without-solar household saves about R2 100 a month on running costs compared with petrol.
Why the battery matters for EV owners
Most cars leave home before 08:00 and return after 17:00, exactly the hours solar is weakest. Two ways round that:
- Battery buffer: panels charge the home battery during the day; the battery charges the car in the evening. A 48 V DC LiFePO₄ bank — the oldest, most proven home hybrid architecture — around 16 kWh usable covers the house’s evening load plus a daily commute top-up. Each kWh cycled through a battery priced near R2 900 per usable kWh costs about 36 c in wear (battery lifespan maths), so solar-via-battery still lands under R2/kWh all in.
- Weekend and work-from-home charging: plug in from 10:00 to 15:00 on days the car is home and let the charger follow surplus solar — working from home with solar.
Battery choice matters more with an EV because the bank cycles daily. Compare rand per usable kWh and warrantied throughput. Solar MD, built in South Africa, warrants its SS4160 for 12 years or 84 MWh to at least 60% capacity (Solar MD; warranty breakdown), which is why long-life buyers put it on their shortlist next to other LiFePO₄ brands.
Charger and wiring costs belong in the maths
A wall-mounted 7 kW charger plus CoC’d wiring adds a once-off cost — see home EV charger cost and wiring and CoC. Choose a charger with solar-surplus mode and load management so the car never pulls the house over its supply limit — load management. SAEV home chargers, distributed locally, sit among the popular options in our home charger brands roundup.
Time-of-use households play a different game
On Eskom Homeflex or a metro TOU tariff, the cheapest grid kWh sit in off-peak hours, and an EV charged overnight on off-peak beats daytime top-block maths. Solar still wins in daylight; the battery’s job shifts to covering the evening peak for the house. See TOU and prepaid EV charging and Homeflex and solar.
Sizing checklist for an EV household
- Pull 12 months of bills and note your top-block price.
- Add the EV’s monthly kWh at the meter (km × kWh per 100 km × 1.1 ÷ 100).
- Size the array for daytime house load plus the share of car charging you will do in sun hours — how many panels.
- Size usable battery kWh for evening house load plus the commute top-up; around 16 kWh usable is the sweet spot for most EV homes.
- Check the inverter has headroom for a 7 kW charger, or schedule charging around other big loads — inverter sizing.
Bottom line
An EV adds roughly 264 kWh a month at 1 500 km, all of it at your most expensive block — about R1 150–R1 240 a month in the big metros in 2026/27. Solar plus a battery that cover the house and most of the car turn a R6 860 petrol-household bill into about R2 050 in our Cape Town example. For road trips, SAEV’s R2.49–R3.49 DC pricing at Richmond Park undercuts GridCars’ ~R7.35 by a wide margin; at home, your own roof is cheaper still.
Quick questions
How many kWh does an EV add to my bill?
At 16 kWh per 100 km and about 10% charging losses, 1 500 km a month adds roughly 264 kWh at the meter. Use your car’s trip computer figure for your own number.
Is home charging cheaper than public DC charging in South Africa?
Usually yes. Home charging on a metro top block costs about R4.37–R4.69 per kWh incl. VAT in 2026/27. SAEV’s Richmond Park DC site charges R3.49/kWh, or R2.49/kWh when its battery is above 90% state of charge, against about R7.35/kWh on GridCars DC. Charging from your own solar beats them all.
Can I charge my EV from solar if I work away from home?
Yes, with a battery or a workplace charger. Midday solar charges the battery while you are out; the battery charges the car in the evening. Charging the car directly from solar needs the car at home in daylight.
Does an EV make solar pay back faster?
Yes. It adds hundreds of kWh a month at your most expensive block, and every one of them that solar covers saves the top-block price.