Vehicle-to-Grid Technology
Imagine your car as not just a mode of transport, but a dynamic power hub, capable of giving energy back to your home or the grid. It could even keep the lights on during a blackout. In this article, we are exploring Vehicle-to-Grid or V2G technology, and how you could get it in your home today. There are already a few homes and small business projects that show that V2G is moving beyond trials—it’s now a real-world option for households and small businesses.
Buying an electric vehicle gives you 2-for-1 deal: a car and a home battery.
Normally when you plug in an electric car it takes electricity from the grid. Vehicle to grid reverses that and allows you to send charge from your car battery to supply the grid. It sounds like a 2-for-1 deal: you buy a car, and you effectively get a home battery as a bonus. On the society-wide level, we roll out electric cars to clean up transport, and we end up with a solution for some of the biggest challenges of an all-renewable electricity grid.
The fact is that cars spend most of their time parked. A fully charged EV battery can power a house for several days. Even though a car battery sounds small compared to a whole electricity grid, together the potential is huge. If all of Australia’s vehicles were electric, the total storage would be vastly more than any grid scale battery like the Hornsdale Power Reserve’s 'Tesla Big Battery.' In fact, it would be over three-day worth of the current electricity consumption of the National Energy Market and five times as large as Snowy Hydro 2.0 and with far fewer delays and cost blowouts.
If all the cars in Australia were electric, the total energy storage would be vastly more than any grid-scale battery, like the Hornsdale Power Reserve's 'Tesla Big Battery.'
What is V2G?
The key to V2G is a bidirectional charger. This allows you to charge your vehicle's battery like normal, but also allowing the vehicle to supply power back to the grid when it needs it. If you can access real time electricity market pricing, then you would in an ideal scenario charge your car when there’s surplus generation, such as in the middle of a sunny day.
On a clear spring day like today here in South Australia, the electricity price is negative, so you’re getting paid to charge your battery. Then later this evening when the sun has set, and everyone comes home to cook dinner the price will likely spike quite high and that’s when you’re going to want to send power back to the grid. So, as well as allowing any car owner to become an energy trader by night, you’re also helping the energy transition by supporting the grid during peak demand and providing extra resiliency.
On a clear spring day in South Australia, the electricity price is negative, so you get paid to charge your battery.
What is V2L and V2H?
Vehicle-to-Load, or V2L, is a function allowing the electric vehicle to power other electric devices or loads, think of it as a mobile power source. Vehicle-to-Home or V2H allows your electric vehicle to supply power directly to your home, which can be particularly useful during power outages or when energy prices are high.
Wine Vineyard: A Pioneer in V2G
In the Barossa Valley, Ballycroft Vineyard and Cellars stands out as a renowned winery owned by Joseph, who developed an interest in V2G technology during a trip to California in 2015. Recognizing its potential to enhance resilience for his winemaking operations, especially during bushfires or other power outages, Joseph took proactive measures to incorporate sustainable energy solutions. To power his winery, Joseph installed solar panels, a BYD home battery, a Nissan Leaf electric vehicle, a Wallbox bidirectional charger and a couple of Tesla chargers.
The vineyard spans 10 acres, making Ballycroft a relatively small winery. Despite its size, the winery is equipped with advanced energy solutions such as Vehicle-to-Home (V2H) and Vehicle-to-Grid (V2G) technologies. With the Nissan Leaf, Joseph can power both his home and the winery, with any surplus energy fed back into the grid.
Joseph's motivation for installing V2G was to achieve self-sufficiency in power. Instead of investing in three expensive stationary batteries, he opted for the Nissan Leaf, which features a 40-kilowatt battery that doubles as a home battery. This approach provides dual benefits, serving both as an energy storage solution and a functional vehicle.
Joseph's motivation for installing V2G is self-sufficiency in power because many wineries in the area use significant amounts of power, and outages can occur during the vintage season.
Joseph shared that the 40-kilowatt Nissan Leaf costs about $52,000. The total cost of their solar panels was around $25,000, and they benefit from a feed-in tariff. Over the past eight years, the investment in solar has already paid off. The Wallbox Quasar V2G converter cost $11,000 with GST and about $1,500 for installation. By using the V2G converter, they save approximately $2,000 annually on nighttime power, leading to a breakeven period of five to six years.
Additionally, they have a BYD 22-kilowatt battery, which cost $20,000. Joseph mentioned that they don't use the Nissan Leaf every night; for instance, if they plan to travel to Adelaide the next morning, they avoid using it overnight. They remain connected to the grid but have relied on grid power only two or three nights this year due to adverse weather conditions like rain, clouds, and storms that hindered their ability to recharge the vehicles and the battery fully.
Joseph noted that many wineries in their area use significant amounts of power, and outages can occur during the vintage season. He mentioned that their current V2G converter does not work when the power is off, but the upcoming model with a CCS plug will function during power outages.
So that's V2G in a small business context. You can see why reliability is front of mind in this case Plus, the cost of all the equipment is a tax write-off, effectively reducing the overall expense. But does V2G make sense for a single household? Would anyone want to invest thousands of dollars to set that up?
V2G in a Domestic Setting
In suburban Adelaide, Jai has V2G technology installed in his home. He has been interested in V2G for some time and purchased a very compatible electric car about two years ago. His setup includes 10 kilowatts of solar power with two inverters, a 10-kilowatt-hour house battery, and 50 kilowatt-hours of storage for the car, which is a significant upgrade compared to the 10 kilowatt-hours of the house battery. The V2G unit costs approximately $10,000, with an additional $5,000 for installation, totaling $15,000 upfront. The house battery cost Jai $13,000, and he bought the car secondhand for $54,000.
The installation process was straightforward, mostly involving assembling the unit, attaching it to the wall, running a cable to the fuse box on the opposite corner of the house, and setting up Ethernet wires through the wall. The installation was completed in a day. Jai noted that the fluctuating electricity prices allow for potential profit by buying power during the day and selling it in the evening. Even without solar, he believes the investment is worthwhile.
Jai recommends installing V2G to profit from fluctuating electricity prices by buying power during the day and selling it in the evening.
In terms of financial benefits, Jai once made $179 in a 24-hour period when the grid connector between South Australia and Victoria was down. Currently, he averages $2 a day in savings, effectively eliminating his electricity costs. His electricity company, Amber, usually provides a credit on the next bill, but if the credits consistently exceed his usage, they pay him. Additionally, Jai appreciates that his system helps stabilize the grid, contributing to lower electricity prices for others.
Can you use V2L to power your home?
It's interesting to note that both projects we've visited have used Nissan Leafs and Wallbox Quasar One bidirectional chargers. The Nissan Leaf is currently the only car in Australia that supports V2G, and the Quasar One is the only approved bidirectional charger available so far. This charger uses the CHAdeMO charging protocol, which is primarily used by Nissan. However, there are many other electric vehicles available now, and Australia is starting to see a wider range of EV options, which hasn't always been the case.
For instance, with Vehicle-to-Load technology, you can plug a laptop into an EV and charge it. So, why can't the same principle be applied to plug into a household battery or use it to power household lights during a power outage? It seems plausible that V2L could easily be adapted to function as Vehicle-to-Home.
It's important to be very cautious with this technology. While some people might be jury-rigging their V2L cars to function as a makeshift V2H setup, this is not advisable without a thorough understanding of the significant and genuine safety risks involved. Car manufacturers do not recommend attempting this, as it can be dangerous. So, remember, kids, don't try this at home.
HOEM: Home Open Energy Manager
Simone is an Adelaide-based YouTuber Simone from Cartel TV. Simone has driven and reviewed almost every EV available in Australia, making her the perfect person to discuss the current V2L capabilities and explore how to use V2L in a home setting using Home Open Energy Manager (HOEM).
Many EVs without V2G capability now feature V2L. In Australia, several models offer V2L, including the Hyundai IONIQ 5, Kia EV6, Kia Niro, BYD Atto 3, Genesis GV60, Electrified G80, and Electrified GV70, with a typical 3.6-kilowatt output. Additionally, models like the Mitsubishi Outlander PHEV and MG ZS EV provide around 2.2 kilowatts of V2L output. It's exciting to see the increasing availability of V2L-capable vehicles in Australia.
Simone plugs the V2L adapter into her Hyundai IONIQ 5, allowing the car to power her home.
The Australian innovation called HOEM converts V2L capabilities into V2H. With products like HOEM, it's possible to use the existing V2L capability of an EV to power a home. This involves having a qualified electrician install the HOEM system and selecting specific circuits to provide power to, such as the study, kitchen, and living area. Given that 3.6 kilowatts are typically the maximum output for V2L capabilities, it won't power an entire home but can supply significant portions of it.
For example, using a Hyundai IONIQ 5, the vehicle-to-load adapter that comes with the car can be plugged into a typical single-phase caravan socket. This setup allows the home to become an accessory that the car can power.
Conclusion
There were questions raised about the global rollout of V2G (vehicle-to-grid) technology. Now, it appears we are finally making significant progress. Although full V2G setups remain expensive and the economic incentives might not be strong enough for those relying solely on the typical solar feed-in tariff, the appeal lies in the reliability and a sense of self-sufficiency that entices the early adopters. The ability to use your car to power your house in a power outage is very appealing, especially since we're just heading into an El Niño now, which in Australia means we will surely have a long, bushfire-filled summer ahead of us.
For example, with a 60-kilowatt-hour battery, one could potentially earn about five dollars by charging during the day and another ten to twenty dollars by discharging in the evening. Over weeks or months, this could amount to a notable sum. Additionally, it helps prevent the grid from needing upgrades by reducing peak demand. The hope is that in a few years, V2G will have become a mainstream technology.
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