Many clued-up Australians dream of their electric car not only taking them places but powering their home and even the grid.
Keep reading, and you’ll discover how Vehicle-to-Grid technology (V2G) could outdo Australia’s entire coal fleet in terms of power delivered (kW) but not energy (kWh) and what that means for our future energy mix.
Coal generates over half of Australia’s electricity, meeting 55% of grid demand over the last 12 months. Solar, wind, and hydro were 37%. The nation’s coal burners – all operated at full whack – could supply 22.46 gigawatts (GW) of power.1 That’s 850 watts for every Australian and their dog.2
Three million V2G-capable EVs could pump more than 22.46 GW into the grid, and Australia has more than 20 million registered vehicles, so it’s not beyond reach. We may even get to three million EVs by 2030.
But the power from EVs is not equivalent to the power from coal-fired power stations. For example, 100,000 EVs pushing out 740 megawatts (MW) for hours differs greatly from Kogan Creek Coal Power Station generating 740 MW for months. V2G is high power, but low energy.3
Australia’s coal fleet can send 18 DeLoreans through time.
Bad News: Most EVs Can’t V2G!
Despite not competing with coal on energy delivered, I swear V2G still has great potential.
But I can forgive you for failing to see it.
Getting the required bidirectional charger is difficult, expensive ($10k) and often not even permitted for grid connection. Even worse, most EVs sold in Australia have no V2G ability. The Nissan Leaf Gen 2 is the only commonly used full EV that can do it.4
We’re still years away from V2G being convenient and cheap. But I hope bidirectional chargers will be like solar inverters and rapidly fall in price. I hope they won’t be like home batteries starting expensive and remaining expensive for a long time.
It looks like a white box, but this is the Quasar 2 bidirectional EV charger. Bidirectional means it can go either way5. (Image: Wallbox)
V2G, V2H, & V2L
V2G has a close cousin called V2H and a step-cousin, V2L.
V2H stands for Vehicle-to-Home. While V2G can supply power to the grid or potentially a home, V2H can only supply power to a property.
An increasing number of EVs now come with V2L. This stands for Vehicle-to-Load and lets you plug appliances into your EV and run them off the EV battery. This can’t be used to power your home — at least not without some electrical gymnastics that Anthony will cover in another post — but it is useful during a blackout or fishing trip.
You can learn more about the difference between V2G, V2H & V2L here.
We Will Have Huge Numbers Of EVs
At the moment, Australia has over 20 million registered road vehicles. Even if we end up with fewer vehicles in total because everyone starts using robo-taxis, there will still be millions of vehicles that could potentially supply power to the grid. Since they’ll be robots, they may even go about it more logically than we would.
Don’t Worry About Battery Wear & Tear
Some say V2G puts too much wear and tear on EV batteries. But if it’s only used to support the grid during critical periods, that’s only a few dozen hours per year. Because wholesale electricity prices can get over $15 per kWh, even this limited use can make V2G financially worthwhile for the car owner.
Other good news is the wear and tear on a 50kWh battery steadily discharging at 7.4kW will be far less than discharging the same amount of energy on the road. Depending on battery pack characteristics, some EV manufacturers may decide it’s insignificant and let you V2G as much as you like. Others may limit it to a set number of hours per year or have it count towards the battery pack’s km warranty limit. Of course, some may be complete dicks and not allow their vehicles to be used for V2G at all. But I suspect Mr Market will fix that. People will prefer EVs that can V2G.
SO… MUCH… POWER!
Most homes have single-phase power and can install an EV charger supplying around 7.4kW of power. I will assume future bidirectional chargers will also allow 7.4kW to be sent into the grid.6
3.1 million EVs could supply 22.94GW beating coal. If only half are plugged in at any one time, then it’s 6.2 million EVs. We may have that within 10 years, and — hopefully — most will be V2G capable.
…and so little energy
An EV with a 50kWh battery pack charged to 70% could supply 7.4kW for 4 hours and 43 minutes. Of course, people won’t want their battery packs flattened, so the actual time will be considerably less. But if you have enough V2G EVs with large enough battery packs, they still can’t provide much energy compared to coal (or any other significant form of generation).
If you had 10 million V2G capable EVs plugged in, each selling 20kWh to the grid, that would total 40GWh. The current coal fleet could supply that at full power in 107 minutes. So even vast numbers of EVs can’t supply substantial energy to the grid. Not unless battery pack capacities start getting ridiculous.
But that’s OK…
High power, low energy doesn’t have to be a problem. EVs are great for soaking up renewable energy when it’s cheap, and V2G will be great for supporting the grid for short periods when renewable output is low and/or electricity demand is high. It will be the job of solar, wind, and existing hydroelectricity to supply most of the energy. New pumped hydro facilities will also provide longer-term energy storage for which V2G isn’t suited.
V2G Is The Way Of The Future, But It’s Hard Work Right now
At the moment, V2G is only for dedicated and enthusiastic early adopters. You’ll need a V2G-capable EV, an expensive bidirectional charger and permission to connect that charger to the grid.
But as EVs go mainstream, V2G should become a standard feature rather than a price-gouging option. Improving battery technology will also reduce wear and tear fears.
I also expect — or at least hope — that the cost of bidirectional chargers will rapidly fall. EV charger manufacturer Wallbox expects their next V2G charger to be 40% cheaper than their current V2G model.
V2G could become as normal as plugging in your phone to charge. And the result? A mostly renewable-powered Australia, supported by the very cars we drive. It’s an exciting future, even for a curmudgeon like me, and it’s closer than you might think.
Footnotes
- this is extremely unlikely due to planned and unplanned outages ↩
- No, wait… if we include dogs, it’s only 684 watts. ↩
- Learn the difference between power and energy. ↩
- There are European EVs that can use V2G in Europe, but so far I haven’t seen an example of them being used that way in Australia. Mitsubishi also has two plug-in hybrids, the Outlander and the Eclipse, that are also V2G capable in Australia. ↩
- Quit it with the sniggering! ↩
- Homes with 3-phase power could provide more, but I’ll say it averages 7.4kW per EV ↩
About Ronald Brakels
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‘wholesale electricity prices over $15 per kWh’.
I hope not in my lifetime…..
We’re already there – just one example:
https://wattclarity.com.au/articles/2021/03/12march-saspike-part1/
There’s no way ordinary people will get wholesale prices for electricity pumped into the grid. The best you could expect is the solar feed-in tariff at about 6c/kWh (mine is going down with the price increases!).
EV’s could be used for grid load management, for those times when too much power is being produced and the price is negative.
I foresee pumped hydro being the main energy storage facility in 5-10 years. Snowy 2.0 is rated at 2GW power for 175 hours + there’s a larger scheme being developed in Queensland. There are many opportunities for further pumped hydro across the country.
Plenty of us ordinary people get access to wholesale prices right now through a provider called Amber Electric.
The forecast sell price for tonight is between $1 and $20 per kWh. Like any forecast, this may not eventuate, but sometimes it does.
We buy and sell at the market spot price every 30 minutes.
V2G is no technical issue at all, but being blocked by the car manufacturers, the coal lobby and their generators and retailers, and of course our government. Not sure why the latter.
Imagine we made V2G mandatory for all new EVs and even allow it to be used!!!
Revolution, savings, environmental benefits, and more. But no, we run a few field tests to keep the masses away from that. Shame.
Only one problem… E Musk doesn’t believe in V2x so no Teslas support it or are likely to. Yes there’ll be other major EV manufacturers, mostly Chinese, who’ll most likely be on board with this but missing out on Tesla leaves a serious hole.
I think you’ll find that changes before long.
Tesla’s will be able to do the V2H or V2G trick sooner rather than later.
In any event, saying Elon “doesn’t believe in it” is not strictly correct. I’ve seen him interviewed on the topic and he has an open mind on the topic. He’s no fool, and will push it through very quickly when the time is right and the tech is there.
Current offerings from some EVs which can power an AC load are more of a gimmick than practical in most cases, maybe useful when camping but not really a lot else.
Not necessarily true – as an example – i can buy an Offgrid Hybrid inverter that will accept 240v on its input and will support charging a 48v battery bank from the input.
IN my case i have a large 48v battery bank that is accessed by my goodwe inverters – if i put this Hybird Offgrid inverter in parallel on the battery bank (which is managed by its own UPS) i can use the GoodWe inverters to power the house (as they currently do on 3 phase) and i can use the car to to supply the 48v battery bank at (say 3KW) so i would be slowly charging the battery bank from the car whilst running the house.
Not the most efficient use of power as you are going through multiple conversion steps – but an easy way to keep the house running in the event of a long outage.
Particularly if after charging up the large battery bank you were to take the car away and recharge at a fast charger
Thanks Craig, great to see and I’d love to investigate this further.
Could you advise the specs of your system and car that have enabled this?
Much appreciated mate.
He wants you to buy his totally overpriced home battery, that is why.
OK, I see: Relatively short duration spikes indeed horribly expensive. I agree, I’d also want to sell all I can at such prices!
But surely in reality the market will find a way to prevent such opportunistic V2G usage?
E.musk doesn’t believe in it because he won’t sell as many powerwalls but hopefully he’ll be forced to change his mind!
I’m not sure fanatics forcing entrepreneurs will end well.
Why do we keep missing the fact that Mitsubishi Outlander PHEV’s are V2G capable and are one of the highest selling vehicles in class? Massive capacity available there to access. Unbelievable that state based power authorities are blocking V2X technology from helping the energy transition. Time to stop subsidising solar generation (RECS) and begin enabling people to put power into the grid when it is needed
So the “plan” is to spend $30B on bidirectional inverters?
At 7kW, you are effectively losing 100km of range every 2 hours. But 2 hours does not cover the night, it doesn’t even cover the peak.
The typical home solar is 6.6kW, so trying to recharge the car after its 2 hour effort supporting the grid will pretty much consume 3 hours through the middle of the day. But what if you take the car to work? No solar charging for you! And you won’t make it to the weekend.
You need to think outside the box here – what will evolve (its already happening in the UK) – i feed into the grid in peak hours when the grid is under duress and i get X amount of credit (say $50) i can then go at my leisure at top up the car at a fast charger in twenty minutes and it costs me x/10 – why would i not do this or plug into a granny charger at work that is provided for free ?
I have just had a client install a 50Kw Solar array on their Warehouse roof – sized for the worse winter days – they will have excess capacity during most days and have implemented granny charging points (15amp) power sockets that are individually switched – and provide power to the staff as they want. If the Solar array is not sufficient to provide power to the business and to the cars we cycle through turning off the active ones on a round robin basis – works perfectly and the customer uses this as a recruiting incentive to their staff.
Craig
I looked hard at V2G must be nearly 20 years ago. v2G can also be great for delivering energy, as cars are mobile. Wholesale costs of electricity can peak at 000’s of $/MWh. So charge one place when power is plentifi and sell it somewhere else when the wholesale price peaks. You can run your car for free under some circumstances!
Clearly Ron, you are an optimist. Who is going to put in bidirectional charging for V2G with the attendant “rules & regulations”, high cost & pittance paid for any energy produced from your EV battery?
Home solar generators have no power in the market, why would anyone think that EV owners would be treated any differently in this so called market? The FIT rates are set by the retailers who have no incentive to pay more than the very minimum required.
Where the power lies is demonstrated by a letter I recently received from my retailer (AGL) informing me of the new rates applying to me from 1 July 2023 on a plan called “Value Saver”. The % Increase was my calculation. AGL neglected to show it!!
Usage Current Rate (c/kWh) New Rate(c/kWh) % Increase
Peak 50.85 62.403 22.7
Shoulder 22.451 33.495 49.2
Off Peak 15.114 25.795 70.66
FIT 5 5 0
Supply 99.726 c /day 111.452 c/day 11.76
I suggest EV owners should forget about saving the grid or even saving the planet and simply turn on their household swing loads.
You are so spot on , if I owned an electric car , ( which I won’t in a million years ) I’d use as a car , not a battery . I have an Enphase battery now in my garage , that I use .
Maybe, but as you explain, you are paying 62c/kWh at peak time. You could avoid that cost with V2G. If you use 5kWh each night which an EV would barely notice had gone missing, you might save $1000/year.
Everyone’s costs/savings will vary and it might not work just now. But it might very soon.
We’ll need to triple our generation capacity and the Grid infrastructure if we keep using the Grid for Electric vehicle charging.
We need to use SOLAR where it is and charge our EV’s that way!
Let’s do it!
Alan Swales
There is no free lunch. what you feed from your car you have previously sucked out of the grid or your own solar power system which you payed $1000s for. No energy is free.
But on some days, energy sold at dinner time is worth two orders of magnitude more than what you bought it for at lunch time.
Presently (until bi-directional chargers drop in price), 3,000,000 EVs x $10,000 each:
= $ 30,000,000,000.
That’s $ 30 BILLION.
Maybe more cost effective to install more BESSs?
I don’t understand why one would do this.
Assuming no solar panels then charging the car will be done at a cost per kWh.
If this same power is then sent to the grid it will presumably at ‘feed in’ rates. Ie much less.
100% agree
I’m all for it. As you say its the way of the future. I’m wondering if a few of us can give it a little push.. ? The No1 problem is bi-directional chargers – 2, or 3 only. Are they actively marketed?
What about solar quotes asking readers who is a likely customer if the price is right. Then ask manufacturers for a quote for say 100, they to obtain AEMO (or who ever) approval. Existing Leaf 2 owners would be the primary purchasers, and if that happened it would start the ball rolling and put pressure on other Car Makers to go V2G.
If Solar quotes doesnt want to be involved because of relationship with solar businesses, no problem. I will assist there, as I’m sure some other prospects would also be.
I want to ask why a solar home battery system charger cant be used, but without the batteries. Or are they all part of the battery box/stack? I’m referring to V2H only.
There’s a fairly big population of Mitsubishi Outlander PHEV’s out there that are V2H (&G?) capable (models after MY19 I think?). Possibly more of them than there are Nissan Leaf? Count me in for the “bulk buy” but only if I get a guarantee that Ergon will permit it on the SE QLD network. I suspect they are far away from allowing it. The other benefit of a V2G charger at home might be faster charging than the vehicle can do on AC. Certainly the case for the Outlander which only has a 3.7kW charger on board.
May i propose a viewpoint that does not hold economics so prominently?
My working premise is that any solar production is primarily for self consumption. Likewise, the energy stored in my EV is for use by the vehicle.
Would someone please explain how or why all these complexities relating to use of EV battery energy to power other things are at all sensible. Are we not omitting the real reason for the vehicle – transport?
The entire matter of generating electricity locally to feed into an electricity grid that is not designed with this in mind will continue to see all these complex ‘fixes’ take up valuable thinking-energy – what’s needed is an entirely new approach, a re-orientation.
From a layman’s stance, would any grid connection to a house etc. that includes a battery of suitable ‘size ‘at the meter box’ (as a condition of connection) not provide a useful solution to many of the problems associated with solar power generation and use?
There must be many, many possibilities!
Oh, the other thing that needs to change is the monetisation and greed associated with home energy production and use. This could be done by restricting publicly notifying electrical energy price once per month, or even better once or twice per year, and of course insisting that the notified values are used.
‘Silly’ ideas, i know. But not more ‘silly’ than all the complexities discussed in other postings.
I agree. People need to do the math. If you use your car for 10000km per yer and charge at home overnight, the cost at a typical off peak tariff of 21c per kWh is $350 a year. Big deal. Rego and insurance are 10 times that.
Charge overnight and stop worrying about saving money using solar. Leave solar for aircon, pool equipment etc.
“Three million V2G-capable EVs could pump more than 22.46 GW into the grid, and Australia has more than 20 million registered vehicles, so it’s not beyond reach.”
Why bother? I’d suggest BESSs would be substantially faster to deploy at greater capacities, probably cheaper & have more reliable availability.
I see more than a dozen GWh-scale BESSs in the development pipeline including:
* Wallerawang 9, 500 MW / 1.0 GWh, NSW DPIE approved 4 Aug 2022;
* Great Western, 500 MW / 1.0 GWh, NSW DPIE assessment phase;
* Liddell, 500 MW / 2.0 GWh, NSW DPIE approved 8 Mar 2022, construction;
* Eraring, 700 MW / 2.8 GWh, NSW DPIE approved 10 May 2022, construction;
* Waratah Super, 700 MW / 1.4 GWh, NSW DPIE approved 21 Feb 2023, construction;
* Orana, 400 MW / 1.6 GWh, Response to Submission phase;
* Mt Piper, 500 MW / 2.0 GWh, prepare EIS phase;
* Wooreen, 350 MW / 1.4 GWh, VIC DELWP application;
* Melton, 1,200 MW / 2.4 GWh;
* Robertstown, 250 MW / 1.0 GWh, SA Gov approved, construction;
* Goyder South, 900 MW / 1.8 GWh, SA Gov approved, construction;
* Bulli Creek, 400 MW / 1.6 GWh, Qld Gov approved;
* Supernode, 800 MW / 2.0 GWh;
* Collie, 1,000 MW / 4.0 GWh, WA Gov approved, construction.
Those listed above total to 8,950 MW / up to 26.0 GWh energy storage capacity possibly available in the next few years. And that ignores the many more sub-GWh-scale BESS projects also in development.
I’m most interested in V2H. A tesla Powerwall only stores 13.5KWH. Even the babyTesla Model 3 stores 60 KWH. Something like the Ford Lightning stores 130KWH. Home solar will become more attractive to me when I can store it cheaply. A Powerwall is not cheap. If I could use an EV for V2H, the whole deal looks a lot better.