Many GivEnergy users will, like me, have an electric car. EVs will typically have a battery capacity 4 or more times the capacity of our home battery. We can transfer energy from home battery to car, but until now transfer from car to home battery has not been possible.
However some EVs now come with V2L (Vehicle to Load), which allows them to supply a 240v load from the car, typically up to 3.6kw.
It would certainly be very useful to be able to freely exchange energy between home and car, particularly in the event of an extended power cut.
Is there any way of connecting an EV with V2L to an AIO with gateway? Could it appear to the AIO to be a solar inverter?
I guess the issue is whether the car will synchronise its output to the home system.
It would be nice to think that GivEnergy are already working on on this, and might give us an update?
I asked about a month or so ago but got no answer.
Such a shame
V2L is still very much in itās infancy, there have been trials but as yet this is not possible. The trials all used the old style CHAdeMO connector so if you had a Nissan leaf it was great. The challenge with V2 H/L/G is that the car battery manufacturers would need to account for additional cycles in their lifespan, something obviously they donāt want to do.
V2L is now part of the CCS standard, and is available in an increasing number of number of EVs. I am aware of many Kia and Hyundai models, the MG range, the new Renault 5, and it is coming soon on the Volvo EX30. No doubt there are others. If the manufacturers are providing V2L, it would appear that they are not greatly concerned about the increase in the number of EV battery cycles which its use would involve; EV battery life is not proving to be a problem.
And many think that Vehicle to Grid has a significant role to play in smoothing the peaks on the National Grid. I am keen to encourage GivEnergy to play a positive role in this interesting development.
Your cause is a nobble one sir and I salute you as I would also like to see this :)
There is a difference here between V2L, V2G and V2H
| Feature | V2L | V2G | V2H |
|---|---|---|---|
| Power Target | Individual devices | Utility grid | Entire home |
| Equipment Needed | Onboard inverter/outlet | Bidirectional charger, grid interface | Bidirectional home charger |
| Use Case | Camping, emergencies | Grid stabilization, revenue | Home backup, tariff shaving |
| Grid Interaction | No | Yes | No (local use only) |
You are right V2L is going into many cars, but itās intended purpose is not for powering a house or feeding into the grid. And this is probably why manufacturers are not worried about cycles and degradation.
Roughly, If I was to power my entire house including a HP using the car battery then in winter my battery would last about 2 days, equivalent to 450 miles of road use, over the period of one winter letās say 30 days of battery cycles, 13000 miles of battery use , suddenly that 8 year guarantee on the battery looks a little risky.
V2L is just that to a load, eg out camping, plug some appliances in.
In order to provide power to the home as an inverter, it would need to output a voltage higher than your home and maintain that with some feedback from teh grid itself. Like an iverter does with its associated grid meter.
V2L is not possible to power the AIO, or your home, while grid tied.
Thatās interesting. Presumably V2H and in particular V2G are designed to deal with the issues you raise, and they are coming soon to some models. Will that help?
The interesting one to watch at the moment would be SigEnergy (similar to the upcoming new AIO design)
They have an inverter, with battery packs 4 or 8 kWh. They say one of these battery packs can be replaced with an EVC that does V2H/G.
Australia have also signed V2G off at all public charging points going forward, so this may have an impact on cars being produced that offer this functionality.
This is clearly a technology to watch but from all that Iāve seen, the standards arenāt there yet nor are the manufacturers of EVās or the government/DNOās.
When the standards and the manufacturers do get there itās likely to be incompatible with the existing EVās and battery storage systems we have as they were not designed for the future standard.
So like many other technological innovations we either hold back and wait for the standards to evolve, or we buy now and have to live with a future replacement being needed.
IMHO when we do get to true V2H or V2G then the home battery market as we see it now will cease to exist as weāll have a far larger battery sitting on the drive.
My question is similar, not having a gateway , in a power cut my solar stopped generating .
If I turn the DNO switch to off !
Could I plug my Honda E into a 3 pin socket to āfoolā the GivEnergy inverter into thinking it has grid power and then start generating and I could run my fridge and internetā¦.
Iāve been told there are considerations to be had when you are running in island mode around earthing and RCDās. Might be possible, but might also be dangerous.
I have a BYD electric car which supports V2L but needs the right connection. I have the myenergi zappi and I donāt know if that would work. Feeding the house from the car battery would allow us to avoid needing heat pumps and use the electricity directly. Electric heating of the home is the best and is slightly more efficient although very expensive. The car battery could then be charged up during the early morning using the Octopus Go tariff, which means a cheaper use of electricity.
The key point above as made by Paul is that V2L is just that, its vehicle to load. So you can plug in a specific load to the car, be that a fridge or microwave at a camp site, etc.
When people are talking about feeding the house that requires a different technology, V2G, vehicle to grid, whereby the inverter taking power out of the car has to synchronise with the grid current. There are some V2G inverters, Octopus have done a trial with them, but they are very expensive and standards are not mature yet so if you do buy one then likely it will need to be upgraded/changed when standards get settled.
Of course there is nothing to stop you getting an electrician to wire your heat pump or even your whole house circuits into a V2L socket that you can plug into the car. You could even have a changeover switch to switch from these things being grid supplied to car supplied. You just canāt plug a car with V2L into the mains and expect it to work.
I donāt think a Zappi can deliver V2G or V2L, but as I understand it, you just need a V2L adapter specific for the car and then āplug inā whatever appliance you want to that socket. Just donāt exceed the car discharge rate, etc. Whether this could support a heat pump, youād need to check the specifications
Update on SigEnergy EVC (DC)
The product in question is the Sigenergy SigenStor EV DC Charger (also referenced as āEVDC moduleā by Sigenergy). Hereās what it does with respect to V2G (Vehicle-to-Grid) and how it works, plus key limitations.
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What it does
ā¢ It supports bidirectional charging (both charging your EV and discharging energy from the EV) at up to 25 kW in the higher-power version (also available at ~12.5 kW) in a DC architecture. ļæ¼
ā¢ With V2G, the EV battery can supply power back to the grid (or virtual power plant / network) ā effectively the vehicle becomes a storage resource. ļæ¼
ā¢ With V2H (Vehicle-to-Home), the EV battery can power your home in an outage or during peak tariff periods. ļæ¼
ā¢ Charger integrates with solar PV + home battery systems via a DC-coupled architecture (so solar panels, home battery, and EV charger share a DC bus) which improves efficiency. ļæ¼
ā¢ It supports smart modes: prioritising surplus solar for the EV, or prioritising battery storage, etc. ļæ¼
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Key technical specs / features
ā¢ Voltage range: ~150 V to 1 000 V DC, which gives wide compatibility with EV battery systems. ļæ¼
ā¢ Max charging AND discharging power (port) for 25 kW version: 25 kW for charging; up to 25 kW for discharging (bi-direction). ļæ¼
ā¢ IP66/IP65 rated weather protection (meaning safe for outdoor installation) and claims of minimal maintenance. ļæ¼
ā¢ Compatibility depends on the EV and its ability to support bidirectional charging (V2X). The charger is āV2X-readyā meaning hardware is present, but EV and grid/utility support are required. ļæ¼
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Limitations / what to watch out for
ā¢ Just because the charger supports V2G doesnāt guarantee your EV supports it. The compatibility of the vehicleās battery system, its on-board charger/inverter and communication protocols matter. ļæ¼
ā¢ Utility / grid/retailer participation: Even with hardware installed you might need your electricity retailer or network operator to accept exports from the EV to the grid and pay for them. For example, one source says if you enrol with a VPP you may not be able to enable V2G: āCustomers who also have a Sigenergy EV charger cannot have the vehicle-to-grid (V2G) feature enabledā under certain retailer programs. ļæ¼
ā¢ Standards and protocols are still maturing: On the product sheet: āV2X functionality is limited by the EVās capabilities. Once the relevant standards are published, V2X feature can be upgraded through OTA.ā ļæ¼
ā¢ Cost and installation complexity: This is a highāpower DC charger integrated with home solar + battery system; it will cost significantly more than a basic AC charger. Some reports from users reflect this. ļæ¼
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Summary statement
The Sigenergy SigenStor EV DC Charger enables your EV to act not just as a load (charging) but also as a storage resource (discharging) via V2G or V2H, provided the EV, grid and installation environment all support it. The system boosts self-consumption of solar, enables backup power for home, and potentially allows energy export to the grid at peak times. But the actual utility depends on compatibility, regulations, and cost.
| EV model | Type of bidirectional support (V2G / V2H) | Notes / evidence | UK relevance / caveats |
|---|---|---|---|
| Nissan Leaf (ZE1 or earlier) | V2G / V2H (via CHAdeMO) | Many sources list the Leaf as one of the few mainstream cars with V2G support. | But UK new sales of CHAdeMO legacy models are declining; also depends on charger / interface. |
| Volkswagen ID series (ID.3 / ID.4 etc) / Audi Q4 e-tron / Skoda Enyaq | Possibly future V2G support | CarBuyer lists VW ID cars, Audi Q4 e-tron, Skoda Enyaq as models featuring the tech among popular models. | Itās not clear those are fully enabled today in the UK Ć¢ā¬ā may be promised or under testing. |
| BYD Dolphin | V2G (in UK pilot / bundle) | Octopus Energy announced UKs first V2G bundle including a V2G-capable BYD Dolphin + bi-directional charger + smart tariff. | That suggests BYD Dolphin is one of the first UK models explicitly marketed with V2G. |
| Renault 5 EV (future) | Planned / slated for V2G | Some sources list Renault 5 among models expected to support V2G. | It may not yet be in production in the UK or have active V2G capability. |
| Kia EV9 | Possibly V2G / V2X | Among models mentioned in general V2G lists / future roadmap in UK context. | As of now, not strong evidence that full V2G is active for UK EV9s. |
| Mitsubishi Outlander PHEV / iMiev / older EVs | Some V2G / V2H support (legacy / trial) | Virta mentions Mitsubishi Outlander PHEV and iMiev as V2G capable in some contexts.Ć | PHEV models may have lower battery capacity; also regulatory / interface constraints in the UK may limit use |
I agree that V2G is a very interesting technology for many of us, but is frustratingly slow in coming.
One thing that should be possible now is to use V2L to drive an individual load in the house, therby reducing the demand on our AIO.
I have an oil boiler driving a large underfloor system, which has 3 pumps, and consumes about 400W. If its on for long periods in cold weather it can easily use 5kwh per day. I could unplug that from the mains and instead plug it into the EVās V2L.
One issue I wonder about is earthing. I assume that the V2L output is floating, with no reference to earth. Should I add an earth? Can anyone knowledgable advise?
In May Daveb01 mentioned V2G in the āupcoming new AIO designā. Have GE published any details of this?
No news on the new AIO Gen 2. They showed it off at one of their shows. So itās the old frustrating saying āComing Soonā
Apparently myEnergi are working on V2X and so is BYD, so all we have to do is wait a time. I donāt think our house is compatible for a heat pump. So far the option has been to place the external pump next to our front door impacting on visitors, route the pipes up to the loft and across and down to the hot water tank. It would also impede people delivery large products, like washing machine.