Vector warns of electric car overdrive

New Zealand’s electricity network may struggle to keep up with the adoption of electric vehicles (EVs), two new reports have warned.

Lines company Vector has released a new ‘‘green paper’’, arguing that it is important that New Zealand has a strong strategy to deal with the uptake of EVs, and what that means for the supply of electricity.

It said the amount of power required to charge an EV with a long-distance battery, at home in the suburbs, would put a strain on existing infrastructure.

‘‘The perception that networks can absorb the uptake of EV charging is only true for the short term while batteries have a short-range capability, customers are satisfied with long charging times and chargers are evenly distributed across the network,’’ it said.

‘‘In Vector’s view, this will change in the longer term as the uptake of EVs increases.’’

Manufacturers expect cars with longer range and larger batteries to be available in the market within the next few years.

If uptake trends continue, one in 15 Auckland households is expected to have an EV by 2021.

Vector said electricity networks were traditionally sized based on the number of houses per street. A customer with a big-battery EV would add the equivalent power needs of one to 20 houses.

Even if uptake was not widespread, Vector said there could be problems if all the EV owners chose to charge during peak time or use faster charging options.

Meanwhile, consultancy firm Concept Consulting said the existing electricity supply arrangements would be a hurdle to the realisation of the potential benefits of electric vehicles.

Concept said a more costeffective time-of-use pricing model would be needed to encourage EV owners not to charge their cars until after 9pm. That would mean they did not pay more than they should for charging – which would slow the uptake of the vehicles, Concept said – and would mean they were less likely to charge during peak times.

Vector said it was likely that most owners would want to keep their batteries topped up.

PHOTO: LUZ ZUNIGA/STUFF One in 15 Auckland households could have an electric vehicle by 2021, which would put a strain on existing electricity infrastructure.