There’s plenty of enthusiasm around electric vehicles but integrating them into the electricity grid raises many questions that we’re still a long way from answering.

Just before Christmas, the South Australia government handed out a series of grants to companies willing to run electric vehicle “smart charging” trials in the state.

The plan is to invest $3.6 million into several pilot programs aimed at solving the challenges of accommodating the state’s growing electric vehicle fleet into a fast-decarbonising grid. JOLT Charge, Chargefox, AGL and the City of Adelaide nabbed spots in the first round, with a second round of grants expected to be announced early this year.  

The pilot program seeks to answer some of the big questions about integrating EVs into the grid: how often, how long, when and where motorists are charging their cars; how to integrate EVs into virtual power plants; and how to sculpt incentives to encourage individual motorists to charge when it best suits the grid.

It’s one of several pilot programs planned or underway aiming to solve the mind-boggling technical and logistical challenges of electrifying transport systems without sacrificing the reliability, security and affordability of energy systems.

Professor Ariel Liebman, program leader for RACE for Networks at the Race for 2030 CRC, is involved with another one of these pilot programs that’s due to start soon. The trial has been informed by an opportunity assessment paper that outlines the predicament these smart charging endeavours seek to avoid.

EVs only make up a tiny proportion of Australia’s vehicles but most of those are currently plugged into any old socket and draw on the grid at the motorist’s convenience. But EV growth is imminent – EVs are expected to make up around 20-25 per cent of the national fleet by 2030, according to optimistic estimates, which will contribute an additional load on the electricity grid of 20 GWh per day. With charging spread out evenly, this shouldn’t be too much of a problem, but the danger is if all EVs are plugged in when people return home in the evenings, the instantaneous load could be over 30 GW, doubling the peak electricity demand. This will be an expensive course to correct, according to the paper’s authors.

The cohort of academics do, however, expect smart or managed charging – where a third party manages electric car charging times on the behalf of a user – to be able to prevent this issue and even improve the performance of the grid. But they also recognise that implementing it will be no easy task.

It will require the formulation of tariff arrangements to incentivise desirable charging behaviour as well as communication standards to ensure devices from different vendors can talk to one another. In fact, Liebman says a whole ecosystem of technology will need to be developed.

“We won’t be able to determine it overnight … it will take a few years of trial and error in terms of standards and control strategies, and pricing strategies.”

While there are several trials underway, including an ARENA-backed AGL trial involving 300 EV owners, he says no one has achieved managed charging at scale yet.

What’s even less advanced is bi-directional charging (otherwise known as vehicle-to-grid or vehicle-to-everything charging), which promises to flip the paradigm entirely and turn EVs into mobile energy storage assets.

There’s an awful lot to do

Before we can expect to see smart charging and vehicle-to-grid charging outside a test lab setting, there’s a lot of ground work to do. To start, it will be important to understand the usage habits of non-smart chargers. Other crucial work will be developing standards and protocols for EV charging equipment as well as rules to command communication pathways between EVs, chargers and stakeholders.

There will also need to be studies to better understand the value EVs could provide to the grid: they may be able to soak up excess solar during the day as well as provide other network services such as synthetic inertia and frequency control. “There are various value components that need to be challenged.”

Also crucial will be getting the incentives right to encourage consumers to participate. Liebman notes that it will be important stay within customer expectations when trying to incentivise specific behaviours.

“There is a lot of evidence that people are reluctant [to participate in network-supportive charging], but are we asking the right questions?”

There may be ways to make it more appealing, he argues. When it comes to bi-directional charging, for example, users could be offered to set the discharge range between a narrow band so the battery level is never too low on their return. Similar settings could also be used to prevent diminishing the battery life. “Customers could choose a discharge maximum and minimum.”

There’s all sorts of monetary options on the table. Time-of-use charging is designed to motivate electric vehicle drivers to charge at times that assist the electricity system. Once EV uptake increases and charging infrastructure becomes more advanced, charging prices may also vary according to location and real time events in the grid so that network congestion can be managed with greater precision.

Something that does concern Liebman when considering the policy settings for EV-grid integration is underestimating the degree of change management. “I do worry that sometimes people working in policy circles propose things without fully appreciating the complexity of what would be involved to implement it.”

South Australia’s smart charging trials

For South Australia, the focus on EVs is a natural progression given the state’s status as a clean energy leader. The state has an $18.3 million EV Action Plan and hopes to see electric vehicles making up 50 per cent of vehicles by 2035. The smart charging trials are part of its efforts.

Through the pilot program, $1 million will flow to JOLT Charge, which runs a network of 21 fast chargers across metro Adelaide, to better understand charging habits – how long, how often, what time of day and for how long. As part of the trial, the company will install more 50kW chargers accompanied with advertising display panels that will hit passers-by with location-based notifications advertising incentives and free charging. The grant will also flow towards an upgrade of its existing mobile app so it can send app notifications that alert people to optimal charging times so that they can charge for cheap.

The idea is to monitor responses from users to see if they how they respond to these notifications and incentives that are designed to spread demand on the network more evenly.

Another $250,000 has been handed to AGL to experiment with its EV subscription model where EV owners get bonus credits on their home electricity bill. The funding will flow towards subsidising these subscriptions as well as EV chargers in three Wilson Parking car parks and chargers and vehicles for a few select organisations: Centacare, Uniting Communities and City of Marion. The idea is to monitor this new infrastructure to better understand the charging behaviour of commercial fleet drivers.

Chargefox also received funding to build a new metropolitan DC fast-charging site. The company will use its app and charger management platform to test how drivers respond to fluctuations in charging price at the fast-charging site.

The City of Adelaide and UPark were also recipients. Funding will help provide commercial fleet EV charging to the parking operator’s customers that will tap into Flow Power’s demand management capabilities to offer charging based on wholesale electricity prices.

More grant recipients will be announced early this year.

By Poppy Johnston.