Charging an electric vehicle (EV) is generally significantly cheaper than refuelling a petrol or diesel car.
This may come as no surprise, but cost savings can exceed 90% depending on the charging method.
At the same time, the cost of public fast chargers has increased, leading some to claim that charging an EV is now just as expensive as filling up with petrol. And in extreme cases, that is also true!
Part of the problem in making sense of EV charging costs is that we are accustomed to seeing fuel costs in cents per litre. And fuel economy stated in litres per hundred kilometres (L/100km).
On the other hand, EVs have entirely new metrics like kilowatt-hours (kWh) for the battery capacity. And their fuel efficiency is expressed as watt-hours per kilometre (Wh/km) or similar.
That's why I decided to equate the two in this simple example.
EV Charging Costs Expressed in Cents/Litre
| Fuel | cents/kWh | cents/litre (equivalent) | Cost Saving |
| Petrol or Diesel | - | 190 | - |
| EV Fast Charger | 60 | 120 | 37% |
| EV Home Charger | 30 | 60 | 68% |
| Charge Off Solar | 8 | 16 | 92% |
| Free Public Chargers | 0 | 0 | 100% |
Make Your Own Calculations
Use the calculator below to re-do these calculations at any assumed fuel efficiency or cost of fuel or electricity. Adjust the numbers for your situation and then click 'Calculate' to view the results.
EV vs. Fuel Cost Calculator
Results
EV Cost per km:
Fuel Cost per km:
EV Fuel Cost Equivalent:
Here's what to enter in each field in the form to get a meaningful result:
Fuel Economy (L/100km) - To get the most reliable figure, you can measure this by recording how far you travel on a full tank of fuel (litres used ÷ distance travelled × 100). Your car may also display an estimated figure. Or you can look it up here. For example, a recent model Toyota Hilux uses 8.4 L/100km of Diesel.
EV Efficiency (Wh/km) - Similar to above, the most accurate figure would be to measure your electricity usage over a given time and distance travelled. However, EVs will generally display an average figure, and you can also look them up in the Green Vehicle Guide linked above. For example, the Tesla Model Y reports a figure of 146 Wh/km, which is not far from my real-world experience of 144 Wh/km (over 30,000 km).
Electricity Cost (c/kWh) - check a recent electricity bill to see how much you pay. Or use your solar feed-in tariff for solar charging. Or check how much a public charger costs. For example, I pay 27 c/kWh for power, get 5 c/kWh feed-in-tariff, and a nearby Tesla Supercharger reports a cost of 62 c/kWh.
Fuel Cost (c/L) - check your local service station or last petrol receipt.
Example Assumptions & Calculation
Here are the fuel economy assumptions I started with. Both figures are typical of Australia's best-selling vehicles, such as those mentioned above.
| Vehicle Type | Fuel Efficiency |
| Petrol or Diesel | 8L/100km |
| Electric | 160Wh/km |
We need to convert cents/kWh into an equivalent in cents/litre. We can start by getting a cost per kilometre with the respective assumed refuelling costs. Here is a worked example for home charging:
- EV cost per kilometre = 0.160 kWh/km × 30 c/kWh = 4.8 c/km
- Fuel cost per kilometre = 0.08 L/km × 190 c/L = 15.3 c/km
- EV cost expressed in c/L = (4.8 ÷ 15.3) * 190 c/L = 60 c/L
