Solar and an electric car in South Australia
An EV adds roughly 1,760 to 3,300 kWh a year, about 4.8 to 9 kWh a day. In South Australia at 42c a unit that is around $1,386 a year on grid power, and it is the single biggest thing that changes whether solar is worth it.
What is different about South Australia
South Australia has the most expensive electricity of the 8 at 42c a unit, which raises what every unit you avoid buying is worth, and one of the lowest feed-in tariffs at 1c, so exporting is close to giving power away and self-consumption carries the entire case. It averages 5 peak sun hours a day.
Why an EV changes the answer
Most households cannot use all the power their roof makes, which is why self-consumption decides the return. An EV fixes that. It is a large, flexible load you can move to the middle of the day, and in South Australia every unit shifted from grid to roof is worth about the difference between 42c and 1c.
Charged entirely on solar you would generate rather than export, that $1,386 a year of driving costs closer to $33. The saving is about $1,353 a year on the car alone, before anything the house uses.
What it does to system size
An EV effectively moves you up a household bracket. If you are here now:
| Household uses | Their bill a quarter | System | After rebates | Saves a year | Pays for itself |
|---|---|---|---|---|---|
| 10 kWh | $482 | 6.6kW solar | $6,250 to $8,250 | $480–$730 | 10+ years |
| 15 kWh | $673 | 10–13kW solar | $8,000 to $13,000 | $740–$1,120 | 9–10+ years |
| 22 kWh | $941 | 10–13kW solar | $8,000 to $13,000 | $1,030–$1,540 | 6–10 years |
| 30 kWh | $1,247 | 10–13kW solar | $8,000 to $13,000 | $1,360–$2,030 | 5–8 years |
Panels only, before the car. Add roughly 9 kWh a day and you are reading the row below.
Which is why it is usually worth sizing for the car before it arrives rather than adding panels later. A second visit costs more than the extra panels would have.
Timing. If the car is more than a year away, the harder question is whether to wait. Panels bought now start saving now, but sized for a household that is about to change. Worth deciding deliberately rather than by default.
$5,000 difference.
That is the gap between two quotes for the same 6.6kW system in South Australia, in the same week. Not build quality, not a better job. Overheads, how full the diary is that month, and what the person at your kitchen table thinks you will agree to. On solar with a battery the same gap is $10,600.
Closing that gap is what I do. I already know what installers in your area are quoting this month for this equipment, so I get you the bottom of that range for the same system other companies charge thousands more for. It costs you nothing. The installer pays me, and only if you go ahead, which is why there is no reason for me to push you at a bigger system than you need or at a dearer installer.
Get your own numbers, then get them priced properly
The table above is four example households. Two minutes of questions gets you your system size, what it should cost after rebates in South Australia, and a ten-year projection built on your roof and your usage. Then I find the bottom of that price range for you.
Run my numbers, freeNo installer buys placement or ranking here, and nothing reaches an installer unless you ask.
Common questions
How much does it cost to charge an electric car in South Australia?
About $1,386 a year on grid power at 42c a unit, for roughly 3,300 kWh of charging.
How much does solar save on EV charging in South Australia?
Around $1,353 a year if the car is charged on generation you would otherwise have exported at 1c.
Should I size my solar system for an EV I do not have yet?
Usually yes if it is within a year or so. Adding panels on a second visit costs more than including them the first time.
How much extra power does an EV use?
Roughly 1,760 to 3,300 kWh a year, or 4.8 to 9 kWh a day depending on how far you drive.