Leaf vs petrol hatch: what the running costs actually look like in Canterbury

NZTA's updated RUC rates have changed the maths on electric vehicle ownership. We crunch the real per-kilometre numbers for Canterbury buyers choosing between a used Nissan Leaf and a comparable petrol hatchback.

The used Leaf market in New Zealand has settled into a fairly predictable range. A 2016 to 2018 Leaf with a 30 kWh battery and reasonable state of health will cost somewhere between $14,000 and $19,000 depending on kilometres, condition, and how optimistic the seller is feeling. A comparable 2016 to 2018 Toyota Aqua or Honda Fit hybrid, same age bracket, similar practicality, will run $12,000 to $17,000. The purchase price gap is narrower than it was two years ago, which is partly post-Clean Car Discount market correction and partly because the Leaf's resale story has become more complicated.

The question most buyers are actually asking, though, is not about sticker price. It is about what the thing costs to run week to week.

Building the cost stack

Start with fuel. An Aqua in real-world Canterbury driving, mixed town and open road, will average somewhere around 4.5 to 5.5 litres per 100 km. Call it 5.0 for a round number. At $2.70 a litre, that is $13.50 per 100 km, or roughly $1,620 to $2,025 for a 12,000 to 15,000 km year. The Fit hybrid is in the same ballpark.

The Leaf's electricity cost depends heavily on how and where you charge. Home charging on a standard residential tariff in Canterbury, roughly 28 to 32 cents per kWh depending on your retailer and plan, and the 30 kWh Leaf pulling somewhere around 18 to 20 kWh per 100 km in real conditions, puts you at about $5.00 to $6.40 per 100 km. That is a meaningful gap. Over 15,000 km, the Leaf costs around $750 to $960 in electricity versus $2,025 in petrol for the Aqua. On that measure alone, the Leaf wins by over $1,000 a year.

Then RUCs arrive.

At $76 per 1,000 km, a Leaf owner doing 15,000 km a year pays $1,140 in road user charges. That narrows the gap significantly. Net annual running cost advantage for the Leaf, on energy plus RUC alone, drops to somewhere between $0 and $600 depending on petrol price, your electricity rate, and how hard the Canterbury winter has been on the battery's effective range.

Where the battery question sits

This is where the Leaf's ownership story gets honest. The 30 kWh Leaf, particularly the earlier 2016 examples with air-cooled battery packs, loses capacity over time and loses it faster in climates with temperature extremes. A Leaf showing 10 or 11 bars on the battery health indicator is not uncommon in the import market, and that translates directly to reduced real-world range. Christchurch winters push the battery harder, and range anxiety on a 150 km advertised range car that actually delivers 90 to 110 km in July conditions is a real factor if you are doing any sort of regional driving.

For my money, the battery health check is the single most important step in any used Leaf purchase, and it is one a lot of buyers skip because they are trusting the dashboard bars rather than pulling the actual state of health data. A leaf spy or dealership diagnostic takes fifteen minutes and tells you exactly where you stand.

The petrol hatch does not have that variable. The Aqua's hybrid battery has proven reliable over time, the system is well understood by Canterbury workshops, and you are never going to drive to Hanmer and wonder whether you have enough in the tank to get home.

The honest annual number

Frankly, if you are doing 12,000 to 14,000 km a year, mostly around Christchurch and the flats, charging at home overnight, and you buy a Leaf with genuine battery health above 85 percent, the running cost maths still comes out in the Leaf's favour even with RUCs factored in. The gap is smaller than EV advocates like to present, and smaller than the petrol lobby pretends, but it is real. Over three years, you are probably looking at $1,000 to $2,500 in savings depending on how all the variables land.

If you are doing 18,000 km a year, mixing highway and town, and relying on public charging more than half the time, the calculation tightens to the point where the difference is within noise. Public charging rates in Canterbury, particularly on the faster DC chargers, can push the Leaf's energy cost up toward $12 to $15 per 100 km, which competes poorly with home charging and starts to look uncomfortably close to the Aqua's petrol spend.

The real objection to the Leaf is not the RUC. The RUC was always going to come. The real objection is that the running cost advantage has shrunk enough that buyers need to actually do the maths for their own situation rather than assuming the EV wins on cost by default. That assumption made sense in 2021. It requires more scrutiny now.