Wireless EV charging: Saving the world One nibble at a time

The Government is pushing us all toward EVs, but can the electricity grid even handle that? Kevin Norquay investigates.

You’re running low on energy so you have a snack during the day to tide you over. Soon electric vehicles (EV) will do the same: ‘‘energy snacking’’ using wireless charging technology on dedicated motorway lanes, in car parks, on taxi stands and bus stops, to the benefit of all, even those without an EV.

An EV that has snacked during the day as it drives around or sits parked, will not be as energy hungry in the evening, which will help prevent massive stresses on the electricity network, as power use rises.

This week $579 million was allocated by the Government for increasing electric and hybrid vehicle use as part of the climate change Emissions Reduction Plan, and an aim to have 30% of cars zero-emission by 2035.

As EVs become affordable – spurred on by Government subsidies and guilty feelings about the environment – there are concerns as to whether the electricity grid could cope, which is where energy snacking can help.

It will reduce EV disincentives such as waits at charging stations, range anxiety, constant worry about plugging in, and wear and tear on electric cables, but vehicle prices remain an issue for now.

While even the cheapest new EV (MG ZS) is nudging $50,000 without subsidies, recent research by BloombergNEF has found electric vehicles will reach price parity with petrol and diesel equivalents by 2026, and become cheaper to produce by 2027.

Increased supply and demand of EVs should help drop prices as they become more mainstream and less niche, though New Zealand’s small market is not a priority for manufacturers.

But when EVs are mainstream, wireless charging will help even the most disorganised driver to keep topped up, as it will happen without them thinking, or without making it crucial they plug their vehicle in when they get home.

Auckland University Professor Grant Covic heads a team looking at inductive power transfer technology systems (charging pads) which wirelessly top up vehicles. Switching to electric vehicles (EVs) is an essential part of meeting international commitments and government policy.

Snacking technology helps battle the issue that electric cars need to be recharged more frequently as their range is less than petrol vehicles, while grid operators worry about meeting peak demand when everyone arrives home and plugs their car in.

Simply put, the technology works and is starting to be deployed overseas, even though as yet there are no wirelessly chargeable cars in the country. There are technical, political and social hurdles to be cleared on the way to the ultimate goal of halving greenhouse gas emissions by 2050.

Among the challenges is how the systems fit into the tarmac, how they survive changes in heat and being driven over, how drivers pay for their energy, and

standardising EV in-road charging so it works for all cars, light trucks and heavy freight transporters.

It’s a move away from ‘‘dumb’’ roading infrastructure, to a smart version with mini charging

stations installed. Who pays and how they pay is under discussion, as is how the technology connects to payment systems, Dr Doug Wilson, a specialist in pavement and economics, says.

With trucks and commercial vehicles making up 7% of the fleet yet being responsible for 50% of emissions, getting them on board is crucial to meet environmental goals.

Trucks need bigger batteries,

‘‘If we can go wireless, then we can start to distribute some energy while it’s on the move, the goal being we can minimise the battery.’’ Auckland University Professor Grant Covic

which subtracts from the amount of load they can carry.

Covic, Wilson and electromagnetic and electronic design specialist Dr Duleepa Thrimawithana are a mix of enthusiasm and care, while talking to the Sunday StarTimes.

On the plus side, they see New Zealand as having the opportunity to export its novel roadway charging technology to the world, as well as producing cleaner and safer

dynamic charging roadways.

Their world sounds idyllic, compared to today’s mix of range anxiety and near constant charging, particularly given the country’s often delicate and temperamental grid.

‘‘One of the concerns the electric industry has is ‘are we going to have to upgrade our transformers’,’’ Covic says. ‘‘If you get five or six or 10 electric vehicles down a street … then unless the vehicles can snack during the day you’re going to end up with some issues on the transformer.

‘‘The other thing that’s really good is that when it goes home, it doesn’t actually need a large plugin supply. It’s only doing a topup, and it’s not that critical.’’

Dr Duleepa Thrimawithana says the looming issue will need to be managed.

‘‘Right now of course, most electric vehicles don’t need that because most of the vehicles are the second vehicles just doing around town work,’’ he says.

‘‘What we need to be able to do is transition all vehicles including a large portion of our fleet and commercial vehicles.

‘‘When they come into play they need to have that capability to be able to charge, and so that needs to be managed.’’

The implications for the higher emitting heavy vehicles (and therefore the environment) are immense, to hear Covic tell it.

‘‘If we can go wireless, then we can start to distribute some energy while it’s on the move, the goal being we can minimise the battery. We can improve the whole system, we’re moving away from the model of carry your energy, you can put some energy in while you move,’’ he says.

Recharging on the move means a smaller battery, less weight, and more ability to up the amount a heavy vehicle can carry. It also means drivers can reduce the time they spend sitting at charging stations, taxi’s will charge on the ranks, buses on bus stops.

Cable charging is an activity people don’t want to engage in, Covic says. His team’s technology will help move people into cleaner car energy.

‘‘It’s an enabler for making things easy and doing what our children want to do, to be free and not tethered to anything.’’