EV + solar finance calculator for South Africa
EV + solar vs current
Illustrative estimate, not a financing offerR2 980
saves 21.9%less per month · R35 761 per year
Current (petrol/diesel + grid)
R13 630
EV + solar
R10 650
EV + grid only
R11 378
Cash break-even
Month 1 · Nov 2026
ChargeShift | EV + Solar Finance report
Illustrative estimate, not a financing offer · 1500 km/month · petrol R30.25/L · grid R3.8755/kWh + R126.25 fixed · solar 8.64 kWp (loan)
EV + solar vs current
Illustrative estimate, not a financing offerR2 980
saves 21.9%less per month · R35 761 per year
Current (petrol/diesel + grid)
R13 630
EV + solar
R10 650
EV + grid only
R11 378
Cash break-even
Month 1 · Nov 2026
Monthly cash outflow — four situations
All figures R per month, first month, constant prices.
- Petrol/diesel + gridR13 630
- EV + gridR11 378saves R2 252
- Petrol/diesel + solarR12 941saves R689
- EV + solarR10 650saves R2 980
Swipe the table sideways for the full breakdown →
| Item | Petrol/diesel + grid | EV + grid | Petrol/diesel + solar | EV + solar |
|---|---|---|---|---|
| Vehicle finance | R7 000 | R7 000 | R7 000 | R7 000 |
| Petrol/diesel | R3 403 | — | R3 403 | — |
| EV public charging | — | — | — | — |
| Household + EV grid electricity | R3 227 | R4 378 | R126 | R1 239 |
| Solar financing | — | — | R2 311 | R2 311 |
| Solar subscription | — | — | — | — |
| Solar upkeep | — | — | R100 | R100 |
| Insurance, service, tyres | — | — | — | — |
| ↳ of which EV home charging (already in grid bill) | — | R1 151 | — | — |
| Grid kWh bought | 800 | 1 097 | 0 | 287 |
| Monthly total | R13 630 | R11 378 | R12 941 | R10 650 |
AI explanation of your bill & scenarios
Lovable AI describes the figures calculated above in plain English. It never changes the numbers.
Where the money goes
Stacked monthly cash outflow by situation
Energy & allocation (EV + solar case)
kWh per month. Solar is counted once across house and car.
PV gross
1 080 kWh
Solar self-used
810 kWh
cap 810 kWh
Grid bought
287 kWh
Solar self-sufficiency
74%
estimate
EV efficiency
18.0 kWh/100km
EV charger-to-wheel
297 kWh
home wall, incl. losses
Public charging billed
0 kWh
Battery usable / day
7.7 kWh
info only
All home EV charging is allocated to solar — but the solar system's finance and upkeep still cost money (shown in R/km below).
Home EV charging: solar, battery or grid?
Typical-day hourly model · annual average · 30% charged in daytime
| EV energy | kWh/day | kWh/month | Share |
|---|---|---|---|
| From solar (direct) | 2.9 | 89 | 30% |
| From battery | 0.0 | 0 | 0% |
| From grid | 6.8 | 208 | 70% |
| Total at the wall | 9.8 | 297 |
Most EV charging comes from the grid. Charging more in the daytime moves it onto solar.
Home charging per day, month by month
Tap “Estimate yield” for your site in section 4 to see how the daily solar, battery and grid split changes through the year. The table above is an average day.
EV charging and grid bill in the four scenarios (per month)
| Scenario | EV solar kWh | EV battery kWh | EV grid kWh | Grid kWh bought | Grid bill |
|---|---|---|---|---|---|
| Petrol/diesel + grid | — | — | — | 800 | R3 227 |
| EV + grid | 0 | 0 | 297 | 1 097 | R4 378 |
| Petrol/diesel + solar | — | — | — | 0 | R126 |
| EV + solar | 89 | 0 | 208 | 287 | R1 239 |
EV grid kWh is already inside the grid bill — it isn't added twice. House on the same day: 11.9 kWh solar, 8.5 kWh battery, 5.9 kWh grid. Unused solar 11.2 kWh/day. Grid bills still use the simple on-site %, so the EV + solar bill may not match this split; switch on “Use hourly charging model in bills” in section 4.
Cost per kilometre & solar value
Petrol/diesel car R/km
R6.94
finance + fuel + running
EV R/km
R5.26
incl. R884 solar share
Solar cost per kWh used
R2.98
vs grid R3.88
Energy savings
R5 391
fuel+grid vs grid+public
Energy savings − solar cost
R2 980
Household ÷ km (not vehicle R/km)
R9.09 → R7.10
EV R/km = EV finance R7 000 + public R0 + EV share of grid bill R0 + running R0 + solar share R884 (solar finance & upkeep × EV share of solar used). This allocation is for R/km only and is not added again to the household totals.
Sensitivity: monthly savings
Kilometres per month vs solar loan rate, all other inputs as entered.
Swipe sideways for all rates →
| km \ APR | 8% | 10% | 12% | 14% | 16% |
|---|---|---|---|---|---|
| 500 | R1 603 | R1 479 | R1 351 | R1 219 | R1 084 |
| 1000 | R2 353 | R2 229 | R2 102 | R1 970 | R1 834 |
| 1500 | R3 104 | R2 980 | R2 852 | R2 721 | R2 585 |
| 2000 | R3 855 | R3 731 | R3 603 | R3 471 | R3 336 |
| 3000 | R5 356 | R5 232 | R5 104 | R4 973 | R4 837 |
More km, low rate: fuel savings grow with distance; cheap solar debt keeps the advantage.
More km, high rate: fuel savings usually still outweigh higher solar repayments.
Few km, low rate: savings rely mainly on household solar offsetting grid costs.
Few km, high rate: most likely to cost more — little fuel to save, expensive solar finance.
6-year cumulative cash flow
Includes deposits, upfront cash, repayments, balloons at maturity, energy, fuel, upkeep and inflation.
Upfront: current / EV+solar
R0 / R0
Year 1 cash: current
R163 557
Year 1 cash: EV + solar
R127 796
NPV of costs @ 10%
R825 932 / R606 311
current / EV+solar
Outstanding at exit
R0 / R0
loan settlements not yet paid
Asset values at exit
R0 / R0
shown separately
Total cost: current
R1 103 073
Total cost: EV + solar
R803 675
saves R299 398
Timeline starts Nov 2026. Balloons appear as spikes in their maturity month.