Weekend Herald

What should you look for in an electric vehicle?

-

When the New Zealand Government ratified the Paris agreement on climate change in 2015 it committed the nation to a 30 per cent reduction in greenhouse gas emissions by 2030. To achieve this goal, half of monthly new and recently imported secondhand vehicle sales must be of either Battery Electric Vehicles (BEVs) or Plug-in Hybrid Electric Vehicles (PHEVs) as the transport sector accounts for 47 per cent of those emissions.

The Clean Car Discount scheme introduced on July 1 offers government rebates to those who register vehicles capable of zeroemissi­on operation (BEV or PHEV) for the first time in this country. So, what should you look for in an electric vehicle if seeking take up the Government’s offer of rebates up to $8625?

The question most people first ask when considerin­g an electric vehicle is, “How far will it travel before I have to plug it in again?” The further a vehicle can travel without recharging the more it will cost to buy, and some widerangin­g BEVs are ineligible for the discount as they cost more than the $80,000 (including on-road costs and GST) purchase price limit of the scheme.

The PHEVs that receive lower discounts have smaller batteries than BEVs and can usually only roam for up to 65km on electric power alone. The first thing to consider on any vehicle eligible for the discount is therefore the size of battery, but there are other factors to ponder as well such as charging times, changes in driving style, charging methods, thermal management of the battery, and cold-weather performanc­e.

Battery Size

The bigger the battery, the more expensive the vehicle and the longer it will take to fully recharge it. Everyone wants more range, and many are prepared to pay extra for more of it, but there are penalties such as increased weight and a demand for recharging via visits to often-busy public fast chargers instead of simpler and far more convenient overnight plug-ins at home.

Some manufactur­ers have recognized that BEVs use less power when driven on urban roads and have specifical­ly tailored the size of their batteries to regular urban journeys. A 25-35kWh battery is all such cars require, and they’ll fully recharge within eight hours when connected into a house plug. Want something bigger? You’ll find that here are several BEVs with 40+kWh batteries and

300+km ranges that meet the discount criteria, costing between $48,000 and $79,000. Want more range still? You can buy a certain Korean compact SUV with a

64kWh battery, but it sits close to the $80K limit with a list price of $78,990.

Charging Methods

If you do opt for a BEV with one of the larger batteries, it’s worth investing in turning your home garage into a recharging station. Just the fitting of a three-phase power supply will halve recharging times, and some BEV-selling brands offer home-charging upgrade packages that increase the convenienc­e of plugging the car in while improving the speed of energy transfer.

With PHEV owners, such upgrading is unnecessar­y as there’s always the combustion engine as a back-up, however, they might like to add their voice to that of their BEV-driving workmates to encourage the installati­on of dedicated recharging facilities at their workplace. That way the PHEV can travel both to and from work without producing emissions.

For some, investment in a second charge lead to be able to recharge at free public stations without leads will be worthwhile. Many of the stations located at Big Shed stores, libraries, and rest homes require EV owners to bring their own lead.

Onboard Car Charge Capacity

The time taken to recharge a BEV depends as much on amount of energy flow the car can accept as the ability of the charging station to supply it. The second thing to check in any BEV’s specificat­ion sheet is therefore the capacity of the onboard charger fitted to every electric vehicle. Within the price limit of the discount scheme there are some

BEVs available that can accept up to 85kW flowing from a DC fast charger, but most limit the energy flow to below that level in the interests of battery preservati­on. It’s not just DC charging performanc­e that should be checked, AC house charging will vary between three and ten kW.

Thermal Battery Management

The bigger the battery, the more heat it will generate when driving the BEV, and thermal management of this energy must be precisely controlled. Some cheaper BEVs rely just on aircooling, including the evergreen Nissan Leaf that is likely to retain its popularity as a secondhand buy under the scheme. This simple battery-cooling solution is why the Leaf can’t have a battery bigger larger than 40kWh. The Leaf’s van cousin, the e-NV200, uses the air-conditioni­ng system to keep its battery cool, a solution adopted by many medium-price BEVs. More sophistica­ted BEVs use a radiator and coolant chambers to keep their batteries operating at optimum temperatur­e.

In colder temperatur­es, these thermal management systems affect performanc­e, particular­ly range. Without the ability to heat the battery, an air-cooled BEV will lose approximat­ely 10-15 per cent of its range when it is used in frosty conditions.

To find out more, visit https://www.nzta.govt.nz/ vehicles/clean-car-programme/ clean-car-discount/

EVERYONE WANTS MORE RANGE, AND MANY ARE PREPARED TO PAY EXTRA FOR MORE OF IT, BUT THERE ARE PENALTIES SUCH AS INCREASED WEIGHT AND A DEMAND FOR RECHARGING VIA VISITS TO OFTEN-BUSY PUBLIC FAST CHARGERS.

 ??  ??
 ??  ??
 ??  ??

Newspapers in English

Newspapers from New Zealand