How does V2G work? An explainer on vehicle-to-grid charging

Late last year the Australian government approved new standards for V2G charging, creating heaps of buzz around the topic. But how exactly does it work, and how likely is it to be in your home any time soon?

The concept is appealing — what if your EV could help power your home or earn you money by selling power back to the grid? That's the promise of V2H (vehicle-to-home) and V2G (vehicle-to-grid) charging.

But as with any new technology, changes can come thick and fast. We’ve got to work through the Discman zone of development before we get to a chic iPod Nano. So what are we currently working with?

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What is V2G and how does it work?

In a nutshell: V2G technology would let your vehicle send energy back to the grid, instead of just taking from it.

For this to work, you need three things:

• A charger that can send power both ways.

• A car that can do the same.

• Smart software to control it all.

Right now, getting all three of these things working together is the tricky part.

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‍What's the difference between V2G, V2H, and V2L?

V2G, V2H, and V2L are all different types of bidirectional charging. “Bidirectional” means energy can go both ways; today it can usually only go into your vehicle, not out of it. It’s uni-directional, if you will. V2G (vehicle-to-grid): your car can send power back to the electricity grid. For many of you, this is an opportunity to make a bit of extra cash by selling your car’s excess energy back to your power company.  

V2H (vehicle-to-home): your car can send power to your home. Earlier this year EV owners in the U.S. were able to keep the lights on during hurricanes thanks to V2H technology. A fully-charged BYD Atto 3 could likely run your household for two or three days; longer if you just used the bare minimum of power needed to be comfortable.

V2L (vehicle-to-load): your car can send power to appliances. In the aftermath of Cyclone Gabrielle last year, New Zealanders used EVs to run fridges and water pumps. Even an older Nissan Leaf could power a fridge and a large water pump for roughly 20 hours; a newer one could do it for around 50. If you’re running a fridge alone, you’ve got 20 to 50 days of power.

V2X: This is vehicle-to-anything, encompassing V2L, V2H, and V2G. While many cars are currently capable of V2L, fewer are ready for V2H and V2G.

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‍Which cars can actually support V2G?

When shopping for an EV, you might hear terms floating around like "V2G ready" and "V2G compatible”. This generally means they have the car component required for V2G — not necessarily the charger or the software. However, there are a few cars that can manage V2H on the market right now, like the Polestar 3 Long Range. See a more detailed breakdown here.

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‍Is V2G legal in Australia and New Zealand?

Yes, it's legal. But just because something's legal, it doesn't mean you can buy it — yet. You might have heard a couple of Australian companies announce V2G chargers for sale, but they’re yet to get final approval from the Clean Energy Council.

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‍How much will a V2G charger cost?

They'll be pricey to start. Current forecasts put the price at above $10k for an installed unit — which means they won’t be for everyone, and the return on investment will likely stretch to 10 years. If someone's promising you a much cheaper V2G charger, they're probably leaving something out.

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‍Will Evnex sell a V2G charger?

Yes, but not yet. As an EV charging company, here's the honest truth: V2G sounds amazing, but it's not quite ready for prime time. Sure, we might see some products hit shelves in the next six months, but there's still a lot of work to do:

• Getting cars and chargers to play nice together.

• Making sure everything's safe and properly tested.

• Working out if it's worth the money.

Evnex is working towards bringing a V2G capable charger to market, but we won't be making any statements until late 2025.

We think you can still get great value from a so-called “V1G” smart charger such as our E2 or X-series. These don’t offer bidirectional capabilities, but they still reduce your costs through soaking up your solar and smart scheduling — and they cost a lot less than a V2G charger.

A smart charger can respond to grid needs by throttling back when demand is high, or charging up when there is too much excess renewable generation. Your retailer will likely give you very favourable rates (or even pay you!) to do this, as has been happening in the UK and elsewhere.  

Our advice? Stay interested, stay informed, but don't feel rushed to jump on the V2G bandwagon just yet. Three years from now you want an iPod, not a Zune.

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