|Electric vehicles: Batteries on wheels can make grid smaller, says network owner|
Giles Parkinson 29 March 2023 6
The owner of the electricity network in the Australian Capital Territory, which has already reached “net 100 per cent” renewables, says the growth of electric vehicles and “vehicle to grid” technology will mean that large amounts of wind and solar can be supported with less infrastructure.
EvoEnergy, which owns and operates about 50,000 power poles and more than 5,000 kms of overhead and underground cables in the ACT, has been hosting a landmark trial of V2G technology over the past two years, featuring 51 Nissan Leaf EVs.
The trial is significant because V2G technology is seen as a potential key component of a future grid where wind and solar is providing the bulk, if not all, of the electricity supply, and demand needs are being managed by short and long duration storage.
While much of the public debate around storage is focused on stationary batteries, pumped hydro and other forms of long duration storage, many believe that EVs, effectively batteries on wheels, can be a key player because the potential resource is huge.
“You can be in a circumstance where where there is a shortfall, and so you’ve got quite a big demand happening at a particular time,” says Peter Billing, the general manager of EvoEnergy.
“If you can draw in, you know, EVs, vehicle to grid vehicles or batteries to tap into to take the edge of that peak, then we don’t need to build as much infrastructure.”
The idea of EVs acting as a grid back-up would have seemed bizarre just a decade ago, and it probably still is for some. But Billing says that network owners are now moving forward, to see how they can embrace the new technologies, including rooftop solar, battery storage, demand management and EVs.
“I think that 10 years ago, networks were kind of thinking ‘what’s happening to our network,” Billing told RenewEconomy. “Whereas now we just see (these assets) as part of the network. What we are doing is still learning, though.”
Billing says the beauty of bi-directional charging will be its ability to turn EVs into an asset rather than a liability, feeding power back into the grid rather than drawing down at peak times.
A lot of this will depend on how tariffs and other incentives are created. For instance, in Canberra in winter the peak demand often happens during daytime hours. And if it has been cloudy, it might make more sense to encourage EV owners to charge their vehicles overnight, when there is often a lot of wind energy.
“So in winter we might be promoting people to be charging at night when the peak might be lower than it would be during the day,” Billing says.
“So with all these technologies evolving evolving over over the next few years, the proliferation of batteries, general storage and vehicle to grid, what does that equation look like. What does the grid need to look like to be able to manage that?”
Billing says it is entirely possible that – as new rooftop solar systems are required to have smart inverters capable of being “orchestrated” by the market operator (i.e, switched off if there is too much rooftop solar output), he says V2G may also become a requirement.
That is many years down the track, considering that V2G is now only possible with older style charging infrastructure known as Chademo, and the V2G standards for CCS charging infrastructure prevalent is yet to be finalised.
It will also require EV makers to introduce that technology on their cars, and for the costs of V2G charging hardware to dramatically reduce so there is a clear and obvious return on investment for both the household and the network or market operators.
Todd Eagles, the head of strategic energy deployments at ActewAGL, the local energy utility, says V2G have proved in their trials that can act like a “swiss army knife” for the grid.
“There is functionality to serve the national energy market, to helps support DNSPs (local network owners), all the way down through to the consumer,” Eagles said.
“The opportunity really is unlocking what priorities are going to be in place in terms of whether it’s a frequency service, a demand response service, or arbitrage from solar in the middle of the day to that evening.
“Doing frequency control is the most difficult thing that we could have selected for this project. But that gives us the ability to send the right signal to the charging market and the vehicle market, and to policy makers across Australia that the capability exists there.
“And because it is like a Swiss Army knife of a Swiss army knife it can be used at every layer across the the energy ecosystem.”
ACT energy minister Shane Rattenbury says the Realising Electric Vehicles to Grid Services (REVS) trial – which used 51 Nissan Leafs – with all but one part of the local government fleet – shows that EVs can play a vital tole in supporting our energy grid and in boosting energy security.
“In the future, we hope this can extend to Canberrans’ privately owned electric vehicles, providing EV owners with the opportunity to send energy stored in their car’s on-board battery back into their own homes or the electricity grid,” he said in a statement.
“South Australia has proven it is possible after becoming the first jurisdiction in Australia to approve a network connection of V2G services in a residential setting.”
See also: V2G charging costs to plummet