Networks gear up to manage EV demand on the grid
As electric vehicles slowly inch their way onto our roads, the poles-and-wires networks that will carry the electricity to charge their batteries are preparing for change.
Not much is known about how EV-owners will choose to fill up their new wagons. Will they all plug in when they get home, ignoring price signals and the collective stress on the grid? Or will they be wise and access cheap solar energy during the middle of the day, possibly supplied free at work?
It’s time to plan ahead, and energy infrastructure owner Jemena is working with three distribution network service providers (DNSPs) on a $3.4 million project to help them understand the effect EVs will have on the grid.
In the trial, the networks will supply 176 EV-owners with fast-charge hardware and network monitoring equipment. Signals will be sent by each network – AusNet, United Energy (Victoria), Evoenergy (ACT) and TasNetworks – to an aggregation platform that will communicate with smart charging hardware at each residence to control EV charging.
The trial will allow the networks to assess the potential costs and benefits of managed charging so they can forecast future expenditure on network infrastructure. If strain on the grid from the transition to EVs can be minimised, all energy consumers will pay less for network charges.
The proposal is for network operators to control participants’ charging, but it’s far from a case of them imposing a rigid doctrine onto consumers who feel they are already doing the right thing by purchasing an expensive new pollution-free car.
“At this stage, the DNSPs will run events and owners can opt out,” says Tim Washington, founder of JET Charge, the Australian company that will supply and install hardware and software for the trial.
If an owner’s charging behaviour looks as though it isn’t helping the cause of calming the grid, that’s too bad – a network will not be able to override an EV owners’ charging habits. “Owners retain absolute control,” Washington says.
The Jemena trial does not integrate vehicle-to-grid charging, Washington says, as “we deliberately wanted to keep it simple and focused”. In Canberra, a similar trial is incorporating the possibilities of bidirectional charging, where 51 Nissan Leaf government vehicles capable of vehicle-to-grid will be on call to dispatch as and when required by the grid.
The Jemena trial has attracted $1.6 million in grant funding from the Australian Renewable Energy Agency.
“As the penetration of EVs increases, it will be important to manage and orchestrate the charging of vehicles to avoid negative impacts on networks and costs and ensure the optimal outcome for all parties,” ARENA chief executive Darren Miller said in a statement. “Networks will be key to this as they hold the ultimate responsibility for integrating EVs into their grids while maintaining security of supply and minimising costs,” he said.
The many virtual power plants (VPPs) in operation or development around the country are being promoted as an obvious alternative to manage the same problem, where aggregators orchestrate widely distributed networks of residential solar-and-storage systems to profit from selling stored energy into the grid when it’s needed most.
The Australian Energy Market Operator’s Integrated System Plan 2020 calls for VPPs as a means to ease the way for distributed energy resources, such as solar and storage, but research from the University of NSW has shown owners of these assets are sceptical about sharing benefits of battery ownership with anyone else, in particular energy companies.
How is a solution orchestrated by DNSPs and reliant on the batteries in EVs – capable of holding many times more energy than a typical residential battery – different?
“Many of the current VPPs are run by retailers who have different commercial considerations to take into account,” Washington says. “A trial run by DNSPs has the sole purpose of protecting low-voltage infrastructure and ensuring maximum penetration of EVs without unnecessary upgrades, thereby saving every electricity user on the network money. I think this infrastructure focus is vital.”