Hikes to ACC levies will see owners of electric cars paying up to $40 more than owners of hybrids or small petrol cars, says an electric vehicle lobby group.
Drive Electric's submission to ACC says electric car owners will pay $109 a year while owners of fuel-efficient hybrid petrol vehicles could pay just $69 and efficient petrol cars $93.
Spokesperson Kirsten Corson says the proposal is "really poor timing" after the government scrapped cash incentives for EVs, imposed higher road user charges and weakened tailpipe emissions standards for car imports.
"It's been spectacularly hard for the sector to adjust. We are seeing dealerships close, we are seeing new low emissions vehicles not being introduced into the market any more, and we are seeing some vehicles being run out and will never come back into our market again."
She said the ACC proposal made "no sense" from an accident compensation perspective, because petrol cars were 15 years old on average, and often less safe than electric cars.
ACC is consulting on changes to the Motor Vehicle Levy, which pays for rehabilitation and care for people injured in car crashes.
Until now, electric car rates have been discounted as part of efforts by the previous government to boost EV ownership rates.
ACC Minister Matt Doocey wants to remove discounted levies for electric vehicles, which ACC says totalled $9.8 million in subsidies over the past three years.
The Minister said owners of the country's 75,000 EVs were exposed to the same risk as drivers of petrol vehicles and should not be paying less than others into the accident fund.
ACC said its had no data to determine whether low-emission vehicles were safer or riskier than petrol vehicles.
The consultation document said it expected removing the discount "to have little or no impact on the uptake of electric vehicles".
Corson said EV owners had no problem paying their share, but the proposal will leave them paying more, despite having typically newer and therefore safer cars.
She said rather than just removing a subsidy, the proposal will actually penalise many EV owners.
According to Drive Electric's calculations, the proposed changes to the way ACC calculates levies will see up to $40 variation in how much different vehicle owners pay for the same number of kilometres travelled.
Cars that use petrol pay a per-litre cost on fuel as well as a flat annual rate, while full EVs and diesel cars pay a higher flat rate only.