Is it cheaper to charge an EV at home or at a public charger?

Home charging is usually much cheaper, because home power costs less per kWh than most public fast chargers. Public charging is convenient for trips but can cost two to three times as much per unit, which adds up over a year.

How do I work out my EV charging cost?

Multiply how much energy your car uses per 100km by your power price per kWh to get the cost per 100km, then scale to your yearly distance. This calculator compares home and public prices side by side.

How much can home charging save?

For a typical driver, charging at home rather than relying on public fast chargers can save hundreds of dollars a year. Charging overnight on an off-peak plan can save even more.

EV Charging Cost Calculator

This New Zealand calculator compares home versus public charging costs for an electric vehicle. Home power costs far less per unit than most public fast chargers, so where you charge makes a real difference over a year. You enter your car's energy use, your yearly distance and the home and public power prices, and the tool shows the cost per 100km and the yearly cost each way, along with what charging at home saves.

Energy use (kWh per 100km)

Distance per year (km)

Home power price (per kWh)

Public charger price (per kWh)

saved a year by charging at home instead of public

Home, per year$0

Public, per year$0

Home cost per 100km$0

Energy use varies with the car, driving and weather; check your vehicle's figure. Most drivers do a mix of home and public charging, so your real saving sits between these. Estimate only.

How it works

The calculator multiplies your car's energy use per 100km by the power price to get the cost per 100km, at both home and public prices, then scales each to your yearly distance. The difference between the two yearly totals is what charging at home saves over relying on public fast chargers. Since most people charge mostly at home and occasionally in public, your real cost usually sits closer to the home figure.

Worked example

A car using 17 kWh per 100km over 12,000km a year uses about 2,040 kWh. At 28 cents at home that is about $571 a year; at 80 cents on public chargers it is about $1,632. Charging at home saves roughly $1,060 a year, and costs about $4.76 per 100km.

Related calculators

EV vs Petrol Calculator: EV versus petrol.
Fuel Cost Calculator: petrol running cost.
Electricity Cost Calculator: power costs.
Car Running Cost Calculator: total running cost.

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