The cost to charge an EV at home is lower than petrol

The cost to charge an EV at home is usually lower than petrol, but your power plan decides the margin. The Electric Vehicle Council says off-peak charging can be up to 90 per cent cheaper. Start with your electricity rate, then account for timing and solar.

How much will home charging add to your power bill?

Your power bill increases by the energy delivered to the car multiplied by the electricity rate that applies while it charges. A kilowatt-hour, or kWh, is the unit your electricity retailer uses to measure that energy.

There isn’t one national home charging price. Your cost depends on your retailer, state, tariff and charging time. The NRMA uses a blended rate of 32.5 cents per kWh for its EV running-cost calculations, covering a mixture of home and public charging.

You can estimate your own cost without knowing the car’s full battery capacity. Find the energy added during a normal charging session in the car or charger app, then multiply that figure by your applicable rate. Using energy added avoids treating every plug-in as a full charge when the battery may only need a top-up.

The NRMA calculated that a BYD Dolphin Dynamic travelling 11,100km a year would cost about $839 a year if every charge came from public DC chargers priced at 60 cents per kWh. That calculation implies annual electricity use of roughly 1,398kWh, although your car and driving pattern may use more or less.

If that same amount of energy cost 32.5 cents per kWh at home, the bill increase would be about $455 a year, or $4.10 per 100km, based on the NRMA figures. Treat that as a worked example, then replace the electricity rate and energy use with your own numbers.

Should you switch to an off-peak tariff?

Switch to an off-peak tariff only if the cheaper charging window lowers your total household bill. A time-of-use tariff, a plan with electricity prices that change through the day, can make overnight charging cheaper while raising the rate at busier times.

The saving can be substantial. The Electric Vehicle Council says home charging on off-peak power can cost up to 90 per cent less than fuelling a comparable petrol or diesel car. It equates the result to paying less than $0.20 a litre for fuel, against about $1.90 a litre for petrol.

Don’t judge a plan by its advertised EV rate alone. Check the rate during the hours when you can leave the car plugged in, then compare the daily supply charge and prices applying to the rest of your household use. The NRMA also notes that some retailers offer discounted or free charging periods to EV owners, but access depends on the plan.

Retail prices move, so an old charging estimate can become misleading. In its 2025-26 Default Market Offer decision, the Australian Energy Regulator increased residential standing-offer prices by between 8.3 per cent and 9.7 per cent in New South Wales from 1 July 2025.

The same decision increased standing-offer prices by between 0.5 per cent and 3.7 per cent in south-east Queensland, and between 2.3 per cent and 3.2 per cent in South Australia, according to the Australian Energy Regulator. Those are safety-net prices, not a substitute for the current rate printed on your bill.

Does rooftop solar make EV charging free?

Rooftop solar can cut the grid cost of EV charging, but it doesn’t make every charging session free. The result depends on how much solar energy reaches the car and what that electricity would otherwise have earned through your feed-in credit.

Price a solar charging session in two parts. Multiply the energy drawn from the grid by your retail electricity rate. For the solar portion, multiply the energy sent to the car by the feed-in rate you gave up by not exporting it.

This method gives you a more honest result than assigning no value to solar electricity. Your retailer bill, solar inverter and charger records can show when the house exported power, imported it or directed it into the car.

Charging while the panels are producing usually gives solar the best chance to cover the car’s demand. If the car is away during daylight, compare the value of scheduled off-peak charging with any solar energy stored in a home battery. Use your actual export and import rates because there is no single solar charging price across Australia.

Best for owners who can leave the car plugged in during solar production or schedule charging for a low-rate overnight window.

Is home charging really cheaper than petrol per 100km?

Home charging is usually cheaper than petrol per 100km, according to the Electric Vehicle Council, provided you aren’t paying public fast-charging prices for most of your electricity. The size of the saving changes with the efficiency of both vehicles and the energy prices used in the comparison.

The following figures use the NRMA comparison, which assumes 11,100km of driving a year and an average NSW price of 189.3 cents per litre for 91 RON petrol during the first half of 2026.

• A BYD Dolphin Dynamic charged at 32.5c/kWh works out to about $4.10 per 100km.
• The same EV using only 60c/kWh public fast charging costs about $7.56 per 100km.
• A Toyota Yaris Hybrid using 91 RON petrol costs about $6.24 per 100km.

At 32.5 cents per kWh, the Dolphin is about $2.14 cheaper per 100km than the Yaris Hybrid in this NRMA scenario. Across 11,100km, that is roughly $239 less for home electricity than petrol.

Public charging changes the order. The NRMA puts the Dolphin at $839 a year when charged only at 60 cents per kWh, compared with $693 a year for the Yaris Hybrid using 91 RON petrol. That doesn’t mean public charging always costs more than petrol because the comparison depends on which cars and energy rates you choose.

The broader Electric Vehicle Council comparison says public fast charging is about 20 per cent cheaper than fuelling a comparable petrol car. That is a much smaller saving than off-peak home charging delivers.

For your own bill, use the rate that applies when the car charges and its recorded energy consumption. If most charging happens at home on off-peak power or daytime solar, petrol is unlikely to match the running cost. If you rely on public fast chargers, check the arithmetic before assuming the EV will be cheaper.