EV running costs in Canterbury: what Leaf and Aqua PHEV owners are actually paying

RUC charges for light EVs have been in place for over a year. We crunch what Leaf and plug-in Aqua owners in Canterbury are genuinely paying compared to petrol equivalents.

Here is what I think: the EV cost advantage is real, but it is smaller than most Leaf owners expect, and for some Aqua PHEV drivers it has essentially vanished on paper.

That is a deliberately uncomfortable claim, so let me earn it.

What the numbers actually say for a Leaf

A second-generation Nissan Leaf, the 40 kWh model that makes up the bulk of the used import market here, will consume roughly 18-20 kWh per 100 km in real Canterbury conditions. In winter, with the heater working and range anxiety causing you to drive conservatively, call it 22 kWh. At a standard residential rate of 32 cents per kWh, that is about $7.04 per 100 km on electricity alone. Add RUC at $76 per 1,000 km and you are adding another $7.60 per 100 km. Total: roughly $14.64 per 100 km.

A petrol Toyota Corolla hybrid, consuming 4.5 litres per 100 km at $2.65 per litre, costs $11.93 per 100 km with no RUC at all.

The Leaf is still ahead if you are on a cheap overnight charging plan. Drop that electricity rate to 18 cents per kWh and the fuel cost falls to around $3.96 per 100 km, making your combined figure closer to $11.56. That beats the Corolla hybrid, but only just, and only if you have the discipline and the setup to charge exclusively off-peak.

The picture darkens further when you account for public charging. A session on ChargeNet's DC fast chargers, which Canterbury drivers increasingly rely on for top-ups during errands, runs at roughly 55-65 cents per kWh. At that rate, the fuel cost alone hits $12.10 per 100 km before RUC is even added. You are now paying more per kilometre than a petrol car that most people would consider efficient.

The Aqua PHEV is a genuinely odd case

The plug-in Aqua sits in a strange middle ground. Toyota's Japanese-market PHEV version of the Aqua has a small 4.3 kWh battery that gives you somewhere between 15 and 25 km of electric range depending on the conditions and how hard you lean on the throttle. Most Canterbury drivers I have spoken to report that their real-world electric range in winter is closer to 12-15 km before the petrol engine kicks in.

If your daily drive is short and you charge every night, the economics are reasonable. At $38 per 1,000 km, the RUC burden is half that of a full EV, and your electricity consumption for 15 km of daily driving is around 2.5 kWh, costing less than a dollar. The rest of your driving is on petrol, where the Aqua's hybrid system earns its keep at around 4.0-4.5 L/100 km.

The problem is that the Aqua PHEV costs significantly more to buy than a standard Aqua hybrid. The PHEV premium on the used import market runs to roughly $4,000-$6,000. If you are saving perhaps $800-$1,200 a year in running costs over the non-plug-in version, the payback period stretches out to four or five years. At that point you are essentially paying for the pleasure of plugging in, not the economics of it.

The Clean Car Discount is gone, and that changes the maths

When the government's Clean Car Discount was still running, the upfront subsidy on EVs and PHEVs helped absorb some of the price premium and made the total ownership calculation look better. That rebate scheme ended in December 2023. There is no replacement. The Leaf that might have attracted a $3,450 rebate now simply costs whatever it costs.

This is not a political observation. It is just the current reality of the market, and buyers who are still doing their homework on the basis of articles written in 2022 are working from outdated numbers.

So does the EV case still hold?

For the right driver, yes. If you own a home with a low-rate overnight charging plan, drive mostly urban kilometres, and bought your Leaf two or three years ago at pre-RUC prices, you are probably still ahead of a comparable petrol car by a meaningful margin over the year. The tax advantage has shrunk, but it has not disappeared.

Frankly, the unreasonable claim I will stand behind is this: the Aqua PHEV, as a pure financial proposition for most Canterbury buyers right now, is hard to justify over a standard Aqua hybrid. The technology is interesting, the electric-first behaviour around town is genuinely pleasant, and the engineering is clever. None of that pays the mortgage.

The whole point of a PHEV is that it bridges the gap between petrol and electric. What nobody told you is that gap now costs extra to stand in.