The Government has defended its proposal to let electric cars use bus lanes despite a study showing it would result in an "unacceptably low level of service".
Its recently announced plan to increase the uptake of electric vehicles, or EVs, in New Zealand includes a target of doubling the number of electric cars on New Zealand roads every year and allowing them to drive in bus and transit lanes.
The main incentive for buying an electric car would be exemptions on road user charges, which would save a car owner an average of $600 a year.
However, experts and environmental advocates criticised the policy, saying permitting EVs in bus lanes would go against everything the Government has done to improve public transport and cycle networks.
In 2011, the New Zealand Transport Agency investigated what impact allowing high-occupancy vehicles on the bus-only separated lane would have on the rapid transit network.
It found it would result in "an unacceptably low level of service for vehicles joining the Northern Busway, including buses in the traffic stream" and did not recommend their introduction.
But Transport Minister Simon Bridges told the Weekend Herald allowing electric vehicles in transit and bus lanes was the "single most effective" non-financial incentive that the Government could do and referenced Norway which implemented the policy in 2005 alongside generous tax breaks. Electric cars now account for nearly one in five of all new cars sold there.
[It would be] an incredibly good problem to have.
However, the incentives were so popular that Norway is now being forced to phase some of them out.
Mr Bridges said having too many electric cars in bus lanes would be an "incredibly good problem to have".
"It's very important to understand in New Zealand our percentage of fleet is 0.025 per cent and so to get to a position where it's causing congestion ... will take an incredibly long while."
However, Greens transport spokeswoman Julie Anne Genter said there was enough difficulty with cars using bus lanes. "Opening bus lanes up to EVs will inevitably mean some abuse by risk takers in petrol cars."
She said EVs will be most useful and effective at reducing pollution in places that have no public transport.