what to install to supply house power from EV?

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Batman

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#319961 19-Jun-2025 08:03

hypothetical:

say you have an EV and you want to use to supplement power to the house, what do equipment needs to be installed (by qualified person of course)?

SomeoneSomewhere

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#3385395 19-Jun-2025 08:14

If you want to supply power to the house (probably a limited subset of it) in an emergency, you want an EV capable of Vehicle-to-load (V2L) and a generator inlet + transfer switch; no different to a small petrol generator.

If you want to supply energy while the grid is still working to offset usage, you need vehicle-to-grid (V2G) but the standards and compliance is very up in the air at the moment.

timbosan

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#3385469 19-Jun-2025 11:03

SomeoneSomewhere:

If you want to supply power to the house (probably a limited subset of it) in an emergency, you want an EV capable of Vehicle-to-load (V2L) and a generator inlet + transfer switch; no different to a small petrol generator.

If you want to supply energy while the grid is still working to offset usage, you need vehicle-to-grid (V2G) but the standards and compliance is very up in the air at the moment.

This has been done using the V2L mentioned about and into a Deye inverter. I don't think they used a transfer switch on this particular setup as its just 'another' source of power like solar. However from reading up on it, it seems the inverter prioritises the generator input if connected, even when there is available solar energy. How to power your home from an EV with V2L - WATTever

If you want a true EV -> house + house battery and always on power, the only one (I am aware of in NZ) is Sigenergy and the V2G DC EV charger unit. You need:

Gateway
Inverter
At least 1 battery
DC Charger

Looking around $20K+ just for the hardware above - the DC charger seems to be around $10K on its own - maybe someone else can clarify pricing. Companies like Lightforce supply and install all the above hardware, but you won't get V2G until regulations changes in NZ. The Gateway is like a transfer switch, so if the mains power dies it instantly transfers to battery, or to battery + EV (depending on configuration, and assuming V2G gets sorted in NZ, etc.). Whilst this video doesn't show the DC EV charger, it does show a lot of details of the gateway + batteries. Better than a Tesla Powerwall? 🧐🔋48kWh Three Phase UPS Battery System! ⚡️ Sigenergy SigenStor

Batman

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#3385483 19-Jun-2025 13:06

thanks, that's a bit much $$

good to know though!

timbosan

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#3385542 19-Jun-2025 13:47

Batman:

thanks, that's a bit much $$

good to know though!

If you don't mind a hack way, the V2L / generator input should work. I looked into it for my solar system, and even if your EV doesn't have V2l (I have a Leaf and it doesn't) you can add an inverter to the battery and just run a cable. Depends on your needs :-)

Batman

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#3385581 19-Jun-2025 17:02

timbosan:

If you don't mind a hack way, the V2L / generator input should work. I looked into it for my solar system, and even if your EV doesn't have V2l (I have a Leaf and it doesn't) you can add an inverter to the battery and just run a cable. Depends on your needs :-)

i don't mind hacks.

how do i install a generator input into my entire house?

Scott3

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#3385604 19-Jun-2025 20:54

Batman:

timbosan:

If you don't mind a hack way, the V2L / generator input should work. I looked into it for my solar system, and even if your EV doesn't have V2l (I have a Leaf and it doesn't) you can add an inverter to the battery and just run a cable. Depends on your needs :-)

i don't mind hacks.

how do i install a generator input into my entire house?

You phone up a sparky and ask them to do it.

They will install a manual switch, with three positions: Mains/Off/Generator. The strict or functionality prevents the mains from livening the male generator inlet plug (socket?), and is prevents the generator from back feeding the grid, as it is not possible to select both concurrently.

The generator switch will be wired to an inlet port on the side of your house:

You then get a V2L cord, that is comparable with your brand of car, and have the sparky (after checking the wire is fat enough) replace the outlet plug with one that matches you houses inlet socket.

https://smartevchargers.co.nz/product-category/v2l-vehicle-to-load/

In a power cut you manually change your house over to "Generator", and then go plug your car to the inlet port, and turn on v2l on the car.

Note the best V2L cars in NZ (Kia / Hyundai) max out at 16A output. A typical house mains feed is 60A (and it has slow blow fuses, so brief current spikes like starting big motors won't be an issue). As such you will need to be quite selective what you turn on.

Generator hookups were discussed here: https://www.geekzone.co.nz/forums.asp?forumid=141&topicid=315556