EV Charging vs Petrol Cost in Australia: The Comparison That Actually Matters

The lazy version of this debate says EVs are always cheaper to run. The opposite lazy version says the higher purchase price cancels every saving. Both miss the factor that matters most in Australia: where and when the EV gets charged. An EV charged mostly from home solar is effectively fuelled for free during daylight hours. An EV charged at home from the grid at off-peak rates costs AU$5-10 per 100 km. An EV charged mostly at public DC fast chargers can cost AU$20-40 per 100 km — close to or above a petrol car's fuel cost. Australia's high petrol prices (AU$1.80-2.20/L) and moderate electricity rates (25-36c/kWh) create favourable conditions for EV running costs — especially when paired with solar. But the comparison depends on your specific charging pattern, not the badge on the car.

EV side

• Annual kWh = annual km ÷ km per kWh
• Charging cost = annual kWh × electricity rate
• Add 5-15% charging losses for home AC charging
• Model public charging separately — it is more expensive

Petrol side

• Annual litres = annual km ÷ L/100 km (÷ 100)
• Fuel cost = annual litres × petrol price per litre

A driver covering 15,000 km/year in an EV averaging 6 km/kWh (about 16.7 kWh/100 km) uses about 2,500 kWh before charging losses. Charging at the Australian average rate of 28c/kWh (from the grid) costs roughly AU$700-800 per year after charging losses. The same 15,000 km in a 6.0 L/100 km petrol car at AU$2.00/L would cost about AU$1,800 per year. That is a AU$1,000-1,100 annual fuel saving — but only if home charging is the primary method.

With solar charging

If the same EV charges entirely from home solar (surplus generation that would otherwise export at 5-8c FiT), the effective fuel cost drops to roughly AU$100-200/year in lost FiT income — or effectively zero if the solar system was already sized for household consumption. Solar-charged EV running costs are among the lowest in Australia.

Public DC fast charging in Australia typically costs 40-60c/kWh depending on the network (Chargefox, Evie, Tesla Supercharger). At 50c/kWh, a 16.7 kWh/100 km EV costs AU$8.35 per 100 km — close to a 4.0 L/100 km hybrid running on AU$2.00/L petrol (AU$8.00/100 km). The charging speed advantage of DC fast charging does not translate to a cost advantage.

1. Solar availability

This is the biggest swing factor in Australia. A driver with a 6.6 kW+ solar system who charges during the day effectively fuels their EV for the cost of lost FiT income — about 5-8c/kWh, or AU$1-2 per 100 km. A driver without solar who charges from the grid at 28c/kWh pays 4-6× more. With solar, the EV vs petrol fuel gap is enormous. Without solar, it is still significant but narrower.

2. Annual kilometres

Fuel savings compound with distance. At 20,000 km/year, the fuel gap between an EV (solar-charged) and a petrol car is AU$2,000-3,000/year. At 8,000 km/year, insurance premiums, registration surcharges, and depreciation may outweigh the fuel savings. Australian drivers average around 12,500-15,000 km/year, so fuel savings matter for most.

3. Petrol price

Australia's petrol price is volatile but consistently higher than the US and many Asian markets. At AU$1.80/L, the per-km fuel cost is moderate. At AU$2.20/L (common in remote areas and during supply shocks), the EV case strengthens significantly.

4. Electricity rate

At Australia's lowest residential rates (VIC/TAS: 25c/kWh), grid charging costs AU$5-7/100 km. At SA's highest rate (36c/kWh), it costs AU$7-10/100 km. Time-of-use tariffs with off-peak rates as low as 15-20c/kWh bring the cost down further.

5. State EV registration surcharges

VIC and NSW have introduced EV registration surcharges (about AU$0.025-0.028/km) to offset lost fuel excise revenue. For a driver covering 15,000 km/year, this adds AU$375-420/year to EV ownership costs. These surcharges partially offset the fuel savings — model them in your comparison.

6. Incentives

Some Australian states offer EV purchase incentives and stamp duty exemptions. The ACT offers AU$15,000 interest-free loans for solar + battery + EV charging. NSW offers AU$3,000 rebates on EV purchases (subject to availability). These reduce the upfront cost gap but do not affect running cost calculations.

Do not compare only petrol receipts against charging receipts. Use a simple total-cost stack:

The EV case is strongest when:

1. You have solar panels and can charge during daylight hours.
2. You drive 12,000+ km/year.
3. Your electricity rate is moderate or you have access to off-peak rates.
4. You can install a dedicated EV charger (Mode 2 or Mode 3 wall box).
5. Petrol prices are at AU$2.00+/L in your area.
6. Your state does not penalise EV ownership with high registration surcharges.

Under those conditions, EV running costs are 60-80% lower than a petrol car.

The petrol or hybrid case stays competitive when:

1. You cannot charge at home (apartment, rental, no off-street parking).
2. You drive fewer than 8,000 km/year.
3. Public DC fast charging is your default.
4. You are in VIC or NSW and the registration surcharge adds hundreds per year.
5. Your insurance quote for an EV is substantially higher.
6. You plan to sell the vehicle within 2-3 years and depreciation risk concerns you.

Solar EV charging is the single most powerful factor in Australian EV economics. A 6.6 kW solar system produces about 26 kWh on a sunny day — enough to charge a typical EV for 150+ km of driving. If the car is home during the day, the charging energy costs only the FiT income foregone (5-8c/kWh), making the effective fuel cost about AU$1-2 per 100 km. Key considerations for solar EV charging:

• Daytime charging is optimal: If your car is at home during school hours or you work from home, daytime charging from solar is effectively free.
• Battery storage extends solar charging: With a home battery, daytime solar can charge the battery, and the battery charges the EV in the evening — avoiding grid import entirely.
• Winter solar production is lower: In TAS and VIC, winter solar production may not fully cover both household and EV needs. Grid charging at off-peak rates fills the gap.
• System sizing: Adding an EV typically adds 2,500-3,500 kWh/year to household consumption. A 6.6 kW system sized for a household without an EV may need expansion to cover EV charging year-round.

Do not treat solar EV charging as free fuel — the solar system has upfront cost, production varies, and FiT export value should be considered. But for running cost comparisons, solar-charged EVs are in a league of their own.

Use the EV Charging Cost Calculator with your local electricity rate and charging pattern. Then compare the full picture with the Australia Solar ROI Calculator to see how adding an EV changes your solar payback timeline. Model home charging and public charging separately before concluding whether an EV saves you money.

EV charging cost in Australia is calculated from km driven, vehicle efficiency (km/kWh), charging losses, and electricity rate. At 28c/kWh grid charging, an EV costs about AU$5-8 per 100 km — about half the AU$12-15 per 100 km for a petrol car at AU$2.00/L. With home solar charging, the EV cost drops to AU$1-2 per 100 km, creating the strongest savings case. The comparison reverses if you depend on public DC fast charging at 50-60c/kWh, which can exceed petrol running costs.