EV running costs two years after RUC exemption ended

The RUC-free ride for light EVs ended 1 April 2024. Two years on, we run the numbers on what Leaf and Prius Plug-in owners in Canterbury are actually paying per kilometre.

Two years ago, losing the RUC exemption felt like a policy footnote. For Canterbury EV owners doing real kilometres in a real climate, it has turned out to be anything but.

From 1 April 2024, light EVs joined every other non-petrol vehicle on New Zealand roads in paying full road-user charges. The rate sits at $76 per 1,000 km. That is the same structure applied to diesel vehicles, and it matters because the entire financial case for running a used Leaf or Prius Plug-in had been built, consciously or not, on electricity being both cheap and RUC-free. One of those things is still true.

What the numbers actually look like

Take a 2015 Nissan Leaf with the 24 kWh battery. These are thick on the ground in the Canterbury used-car market, sitting anywhere from $9,000 to $14,000 depending on battery health and kilometres. In summer, a careful driver might average 6 km per kWh. In a Christchurch winter, with the heater running and the battery preferring not to be below 10 degrees, 5 km per kWh is more honest. On a standard home night rate of around 28-32 cents per kWh, that puts electricity cost at roughly 5.5 to 6.5 cents per km before RUCs.

Add the $76 per 1,000 km RUC and you are at 13 to 14 cents per km in energy and road-user costs combined. For 15,000 km per year, that is around $1,950 to $2,100 in running costs from those two line items alone.

Now compare a 2015 Toyota Aqua, the obvious petrol Japanese import alternative at similar money. Petrol is sitting around $2.60 per litre in Christchurch at time of writing. The Aqua returns around 22 km per litre in mixed driving, call it 20 in winter with the heater going. That is 11.8 to 13 cents per km in fuel. No RUCs. No licence purchases to manage.

The gap, which once looked decisive in the Leaf's favour, has largely closed.

The Prius Plug-in is a different animal

The Prius PHEV calculation is messier and the messiness is instructive. The generation most commonly seen here, the ZVW52 from around 2017 to 2022, has an electric range of roughly 25 km before the 1.8-litre petrol takes over. NZTA requires PHEV owners to hold a RUC licence only for the electric kilometres driven, which means tracking them separately. In practice, most Canterbury owners are running petrol the majority of the time.

If your daily commute is under 25 km and you charge at home every night, the PHEV proposition still holds. You are using almost no petrol and your RUC exposure is real but bounded. If you are doing 50 km days or longer, you are effectively running a petrol hybrid with a heavier kerb weight and a more complex drivetrain. The fuel economy in that mode is good, around 4.5 L/100 km, but the purchase premium over a standard Prius is hard to recover.

For my money, the PHEV case was always thinner than the marketing suggested unless your driving pattern was almost perfectly suited to it. The exemption ending has not ruined the Prius Plug-in, but it has removed the margin for error.

Do the sums still stack up?

Frankly, the Leaf still makes sense for the right owner. If you are charging at home on a low overnight rate, doing mostly urban kilometres, and you bought the car two or three years ago before prices softened, you are probably still ahead. The servicing costs are genuinely lower. There is no cambelt, no exhaust, no oil changes. A well-maintained Leaf is not an expensive car to keep on the road.

The real objection now is the buyer who was borderline on the financials and leaned on the RUC exemption to justify the decision. That person is now paying petrol-comparable running costs with a car that has range anxiety built in, a battery that ages visibly, and a resale market that has cooled since the Clean Car Discount disappeared at the end of 2023.

Let's not pretend the 40 kWh and 62 kWh Leafs are in the same conversation. They are better cars with better range and better cold-weather performance, but they also cost more to buy and the RUC liability is identical. The maths is tighter than it was.

A 2015 Aqua at $10,000 with 80,000 km on it will cost you almost nothing to maintain, return honest fuel economy, and ask very little of you. It is not exciting. The whole point of buying one is that it does not need to be.

The EV still wins on emissions and on the satisfaction of driving something genuinely different. Whether it wins on pure cost depends entirely on how you drive, where you charge, and how honest you are with yourself about both.