The real cost of an EV versus a petrol car

An EV can cost much less to power at home and may need less routine maintenance, but that does not guarantee the lowest total cost. The purchase-price gap, finance, insurance and depreciation can outweigh several years of energy savings. Use the same timeframe, distance and vehicle type for both cars.

A worked Australian energy example

Consider two similarly sized cars driven 12,000 km a year. The EV uses 15 kWh/100 km, with 10% added for charging losses, and is charged at an illustrative $0.30/kWh. The petrol car uses 7.0 L/100 km at an illustrative $1.90/L.

Illustration only—not a forecast or national average. Public fast charging, solar, time-of-use tariffs, fuel prices, climate, traffic and driving style can materially change the result.

What changes the EV result?

Home charging usually produces the strongest energy-cost case. An owner with rooftop solar or a low off-peak rate may spend less than the example. A driver relying heavily on public DC fast charging may spend considerably more. Charging losses also mean the energy shown on an electricity bill is higher than the energy added to the battery.

Use the Australian Government's Green Vehicle Guide calculators with your actual electricity tariff, petrol price and kilometres. For an EV, split the calculation between home, workplace and public charging rather than applying one optimistic rate to every kilometre.

Purchase price and depreciation matter most

Depreciation is often the largest cost of owning a newer car, but future resale value is uncertain. Compare today's actual drive-away prices for equivalent size and equipment, then test more than one resale assumption. A $5,000 higher purchase price cannot be ignored simply because the EV saves about $1,000 a year in an energy example.

Discounts can move the calculation quickly. Use the contracted price rather than the recommended retail price, and include dealer delivery, on-road costs, accessories and any home-charger installation. If financing, compare the amount borrowed, interest rate, fees, term and balloon or residual—not only the monthly payment.

Servicing, tyres and repairs

Australian Government guidance notes that EVs have fewer moving parts than petrol or diesel cars and typically still require regular inspection. Use the manufacturer's published service schedule and capped-price figures where available instead of assuming an EV has no servicing cost.

Insurance and registration

Insurance is vehicle-, driver- and postcode-specific. Obtain real quotes for both cars before deciding; repair networks, parts prices and agreed value can create a larger difference than expected. Registration and compulsory insurance also vary by state or territory, so use the same location and registration period.

Build a five-year comparison

When does an EV make the strongest case?

The numbers tend to improve when the EV's drive-away price is close to the petrol alternative, the car covers regular kilometres, most charging happens cheaply at home or work, and the owner keeps it long enough to recover any upfront gap. The case weakens when an expensive EV replaces a much cheaper petrol car, annual distance is low or most energy comes from high-priced fast charging.

The fairest conclusion is personal: calculate both cars with your inputs, then consider the non-financial differences—quiet driving, home fuelling convenience, performance, emissions, touring stops and whether the vehicle suits the household.