Vehicle-to-Grid (V2G) Explained:

“We’re working with Australian research organisations to test V2G technology, to test charging systems, to test EVs. And we’re working on the standards and regulations regarding the safe export of energy from EVs, through chargers and into the home or grid.

“Hyundai is also the only original equipment manufacturer (OEM) in Australia currently taking part in the Vehicle-Grid Network (VGN) funded by the federal government and the Australian Renewable Energy Agency (ARENA). We’re committed to its development” 

“That said, we neither support nor permit V2G charging of any Hyundai EVs in Australia at this time.”

Is V2G a new technology?

Although it’s been making waves recently, V2G is not a “new technology”, exactly; its formal framework was actually invented in 1997 by Doctor Willett Kempton and economist Steven Letendre at the University of Delaware in the United States, with the first practical trials held in 2007. 

Since then, dozens of V2G pilot programs have been launched worldwide, including one recently held in Australia by energy provider Amber Electric. But while the technology has technically existed in various forms for more than 25 years, it’s only just starting to move out of the experimental trial phase. 

V2G is, therefore, not so much a new technology as an emerging technology, and like any emerging technology, it presents its own unique set of challenges – and benefits. 

What are the benefits of V2G technology for EV owners?

The potential benefits of V2G charging are considerable, provided that it’s done safely and in strict accordance with any applicable laws, regulations and guidelines. 

By using bidirectional chargers, EV owners can:

• feed their EV’s electrical energy into the grid during peak periods – V2G charging – to help balance grid demand, reduce reliance on fossil fuels and even earn passive income.  
• feed their EV’s electrical energy into the home – a process called vehicle-to-home or V2H charging – to help power their property and reduce their household energy costs; 
• feed the grid’s electrical energy into their EV grid during off-peak periods – known as grid-to-vehicle or G2V charging – to charge their vehicle, at a lower cost, using renewable energy. 

And, as Scott points out, there are environmental benefits, too. During off-peak periods when power demand is low, the grid mostly operates using renewable energy sources – solar energy, wind energy, etc. So by using an EV to absorb that clean surplus energy and feed it back into the grid during peak periods, the reliance on carbon-intensive fossil fuel "peaker" plants can be reduced significantly.

“V2G technology presents a great opportunity as the world switches from fossil fuels to renewable energy," Scott says, “And EVs play a key role in that: they can help support the grid during peak periods, when demand is high, and then be recharged during off-peak periods, when demand is low, all while using clean, low-cost energy. It’s exciting stuff.”

How does V2G work? 

V2G works using three key components: 

1. an EV

2. a bidirectional charger

3. the power grid

Here’s what the flow of electrical energy looks like between these components, first via V2G, then Grid-to-Vehicle (G2V).

And here’s how V2G works in seven simple steps, using an everyday example.  

1. An EV owner plugs their V2G charger into their V2G-enabled car, opens a V2G charging app on their smartphone and selects their charging requirements – for example, their EV needs at least 80% battery by 7:00 AM the following day (for, say, their commute), but any remaining charge can be sent to the grid overnight.

2. The V2G charger and EV perform a “digital handshake”; the car identifies itself to the grid, and the grid receives essential data from the car, such as the battery’s charge and temperature. This is done using a universal communication standard called ISO 15118.

3. The V2G charger communicates with what’s called an aggregator – i.e. a cloudbased software platform run by an energy company – which monitors the electrical grid in real time. It assesses two things: grid demand and electricity prices.

4. During a peak period when demand and prices have risen – at 7:00 pm, for example, when lots of people return home and start turning on electrical appliances like TVs, ACs, etc. – the grid sends a signal to the aggregator that more power is required.

5. To prevent a utility provider from firing up a coal or gas peaker plant, the aggregator passes on that signal to the V2G charger, which then pulls direct current (DC) electricity out of the EV’s battery, transforms it into alternating current (AC) – the type used by homes and the grid – and sends it to one of  two places. Either a) to the owner’s home to help power the property, or b) through the owner’s home and into the grid. In the latter instance, the utility provider then credits the EV owner’s energy account as their vehicle has just helped to stabilise the grid when demand was high.

6. Hours later during an off-peak period, when both electricity demand and prices have fallen – for example at 02:00 am, when most people are asleep and their electricity usage has declined – renewable energy farms start producing excess energy. Detecting this excess, the aggregator sends the inverse signal to the charger; that more power is no longer required by the grid, and that the EV should use this renewable energy to recharge.

 7. The opposite process begins; vehicle-to-grid charging reverses to grid-to-vehicle (G2V) charging. The charger pulls the cheap, clean AC energy from the grid, converts it back to DC and sends it to the EV’s battery so it can charge to 80% by 07:00 AM, as requested – this time at a fraction of the cost compared to charging in a peak period.  

So, to recap: using the above example, the EV owner has charged their EV using the grid, their home using their EV and the grid using their EV. That’s why it’s called a bidirectional EV charger – it employs a two-way exchange of electrical energy.  

Plus, not only have they charged their EV using renewable energy, and at a lower cost; they’ve also earned some passive income and helped their fellow Australians by reducing strain on the grid. Everyone wins.   

So what’s the catch? And if it’s so simple, why isn’t every EV owner using V2G chargers already?