But until now, there’s been a missing piece of the puzzle. The batteries in most new electric cars are huge – much larger than a typical home battery. A BYD Seal might have a battery capacity of 60 to 80 kilowatt hours (kWh), while the average home battery installed in Australia is 11 to 12 kWh.
So why can’t you plug your car in and power your house?
Soon, you will be able to. The suite of technologies already exists. They’re known as vehicle to grid (V2G, where you export power to the grid), vehicle to house (V2H, where you run your house off your car) and vehicle to load (V2L, where you run electric devices off your car).
There’s a cost – you need a bidirectional charger able to send power both to and from the car. But experts expect substantial benefits.
With V2G, you can sell power back to the grid at peak times, helping the grid stay stable. With V2H, you can weather power outages or even go off grid. V2L would be useful for campers and tradies.
One reason it’s not here already is that regulations and processes haven’t been in place. On Saturday, climate change minister Chris Bowen announced progress on this front. Vehicle to grid would be up and running by Christmas. That’s a very ambitious timeline, as there’s more to it than just regulations. But it is a jump forward.
“When you pick your next EV you won’t be buying just a car, you’ll be buying a household battery on wheels,” Bowen has said.
What changed?
Vehicle to grid isn’t totally new in Australia.
In late 2022, South Australia became the first state to greenlight bidirectional chargers in homes. But these chargers only work with two EV models, the electric Nissan Leaf and the plug-in hybrid Mitsubishi Outlander.
So what just changed? Crucial underpinning – the boring but important scaffolding which makes new technology robust and reliable. Specifically, Standards Australia has approved a new standard for bidirectional chargers.
Australian standards are technical standards outlining specifications and guidelines for new technologies. While voluntary, products are expected to meet the relevant standards. A V2G standard will level the playing field and give clarity for owners, grid operators and electric charger manufacturers.
A new standard is a leap forward. But to make V2G a reality will take more action. Car owners have to install bidirectional fast chargers, able to send power both ways. These aren’t cheap, at around A$3,500 a pop. Car companies have to ensure their chargers meet the new standard. And distribution networks have to approve charger models for use on the grid.
Trial projects such as the Realising Electric Vehicle-to-Grid Services in the Australian Capital Territory and the Amber/ARENA trial in New South Wales show we can meet some of the technical requirements. It will take time and money to integrate these changes nationwide.
Why should we be excited about this?
As more car owners go electric, the size of the battery fleet on Australian roads and driveways is growing fast.
Without V2G, these batteries are just used for one thing – to make a car, truck or bus operate. But these batteries could do much more. Australia’s electric fleet is now over 180,000. If the average battery pack size was 50 kWh, that would represent a giant distributed battery of 9 gigawatt hours. The largest grid-scale battery under construction in Australia will have 2.4 gigawatt hours.
For energy authorities, this fleet of batteries presents a huge opportunity. At times of peak demand, they could offer financial incentives for EV owners to discharge to the grid. Used carefully, EV batteries could avert blackouts. A decentralised power source is more resilient to shocks. It could mean avoiding the need to fire up expensive gas plants at times of peak demand.
For EV owners, the financial incentives could be enough to let their cars be used to keep the grid stable. In testing, early V2G users have been able to turn large power bills into power payments. Annual earnings could be as high as $9-$12,000 per vehicle in New South Wales, according to one report.
Many carmakers are moving towards including V2G.
2025 could be the year
Overseas, vehicle to grid technology is gaining traction. California has mandated V2G capabilities in all light EVs sold from 2027 onward.
In Australia, regulatory change and incentives will be needed to encourage broader adoption.
It’s encouraging to see Australian standards for V2G arrive. But while Bowen is pitching V2G as about to happen, there is still some spadework left to do before it’s really here.
Syed M Nawazish Ali, Research Fellow in Transport Electrification, RMIT University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Even at $3500 it's about what you'd pay for to connect a small and expensive home battery to your home and the grid.
I assumed the $3500 was for the hardware, should cost about the same to connect as a battery.
"Australian standards are technical standards outlining specifications and guidelines for new technologies. While voluntary, products are expected to meet the relevant standards'"
Great news. I hope the emissions reduction standards aren't voluntary.
"It could mean avoiding the need to fire up expensive gas plants"
Excellent, because they are just sitting around twiddling their thumbs until called upon like the police, ambulances and fire brigades.
"V2G users have been able to turn large power bills into power payments Annual earnings could be as high as $9-$12,000 per vehicle in New South Wales, according to one report."
Incredible!
As in, not credible.
About bloody time.
However, some red-necked, contrarian fossil-fuel puppet will make s lame ass phantom claim of it damaging the grid.
Awesome news... I've been recently looking at a home battery, and was close to selecting an installer, but as I already have an EV which mainly lives in the garage, it may be smarter for me to wait and spend a third of the home battery cost on new V2X technology so I can use that existing and under-utilised resource.
It will depend on your current EV model as to whether you will be able to use it for V2G. I'm guessing that a lot of potential EV buyers are sitting on their hands until V2G is clearer for their locality.
You are still going to have a car that is compatible with the standards for these changes to apply to existing EVs. Essentially this means bi-directional chargers. Some cars are capable but they may not get compliance so may remain legally incapable of discharge.
I believe that the EV's battery supply should complement a fixed home battery. IE: if you can, have both.
Perhaps looking to the future, a small capacity battery may be all that's required, but if one's lifestyle & work obligations means taking the car away from the home during a time when a battery would be required, then at least you have some battery backup.
However, if you choose to only power your home with your car's battery, then you might just have to purchase from the grid if timing is wrong. In addition, you need to ensure the EV's battery has enough charge for powering the home and then driving to work or wherever needed the next day.
For me, I'm going to have a fixed home battery installed soon and hopefully buy my first EV in 2025.
Enough charge (kWh) to power your home might not be the bottleneck in most cases, but the maximum discharge power (kW) of the current crop of V2L-capable EVs might very well be. Your suggestion to combine the EV's battery supply with a home battery system is one possible way of overcoming that limitation.
I am on the hunt for some expert advice regarding an interim V2L-to-Home setup I could implement in my home while I wait for an affordable V2G wall charger. My current thinking is to get a wall socket installed that I can connect my V2L cable to from the EV, then have a switch that island's the house from the grid so all house power can be drawn from the car battery. I envisage this approach can be used late at night while I sleep and do not need to recharge the EV as my overnight loads are usually less than 0.5kWh. Any thoughts anyone?
A 'Generator Switch' on your switchboard, like https://www.sparkydirect.com.au/p/HAGER-SF263-Changeover-Switch-2-Pole-63-Amp should do the trick, though a timer and relay might be nicer.
Mind, each time you switch it, mains-powered clocks will reset.
How does the V2L deal with overloads, like an aircon or heater coming on? I guess it trips and needs reset?
As I understand it there will be a device that will regulate, communicate, schedule, control, and provide automatic switch off grid connection during outage and back on when it returns. i.e. full backup if you have capacity in your inverter.
Check out the solar quotes website. They did a story on how to do this a couple of months ago.
Was thinking of selling my Nissan Leaf, not now🙂
“Car owners have to install bidirectional fast chargers, able to send power both ways. These aren’t cheap, at around A$3,500 a pop”
What “bidirectional fast chargers” are available at that price? I think that you’re out by a factor of three, I haven’t seen an installed example below $10 000. Please let me know where I can get one for 3.5k.
IMO the distinction between VTH and VTG is less important than whether the car does bidirectional AC or DC.
In Australia, we already commonly have large solar inverters capable of taking DC power (from solar panels) and managing the distribution of that to the house, and/or sending surplus to the grid. If the car supports DC connection to a similar (or the same) device, it would only have to work in a very similar way, and should fit well within existing electrical standards for inverters.
If the car generates its own AC, then the car has to be responsible for synchronising phase with the grid, anti-islanding, and somehow integrating with your solar generation (which it doesn’t know about), so there is a lot more involved, a lot of new use cases to cover in standards, and a lot of car manufacturers having to learn how to do home energy management (not necessarily something they’re good at).