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points by thanhhaimai 1 day ago | 0 comments

I ran the fridges and essentials with my Ioniq 5 the last time there was an extended power loss.

I don't think the residential power generator is needed anymore if you have an electric car.

I have a Tesla Y. It has almost a week of power sitting in it on full charge. There's no hookup. The only power outlet is usb-c pd.

Completely missed opportunity. I won't be buying an electric vehicle that doesn't allow powering my house, ever again.

[–] Diederich 1 day ago

I have a 2017 Tesla S100D. (Yay back when we had letters and numbers!)

As you probably know, there's a 12 volt battery in these cars. That battery is automatically recharged by the big 100kWh main battery.

Some years back, I bought a 12 volt, 2000W inverter and connected it to this 12 volt battery in the Tesla, ran a couple of extension cords, and powered our refrigerator, extra freezer, and a number of other things with it for many hours. The main battery percentage in the car showed an appropriate drop. This actually wasn't during an outage, it was contingency testing. We already have a natural gas, 3600 watt generator that connects to one of our panels and use that during (unfortunately frequent) outages.

In my 2017, it's a bit of work to get to that battery, but it's quite doable and seemingly quite safe. The obvious, very rough/estimated/simplistic math is the 100kWh main battery divided by 2kW is about 50 hours. Different factors would push that number up and down of course.

[–] jvanderbot 1 day ago

During an outage I tried the 12v and found it was unable to surge the freezer box. Now, the inverter I used wasn't great, but IIRC I read they didn't allow significant current off the cig lighter outlet.

I will definitely try this again. If it works, that'd be great.

[–] mylies43 1 day ago

Doesnt powershare just work via the charging cable? It is a advertised feature of the Y

[–] hocusPokeUs 1 day ago

https://www.tesla.com/powershare/#vehicles

Only available on Tesla models ordered after October 1, 2026

Tesla models older than 6 weeks are SOL (for now? Maybe it just needs some backwards compatibility testing)

[–] josephcsible 1 day ago

> Tesla models older than 6 weeks are SOL (for now? Maybe it just needs some backwards compatibility testing)

It sounds like it will require a hardware retrofit, that isn't being offered to consumers yet: https://www.notateslaapp.com/news/4585/tesla-publishes-vehic...

[–] cyberax 1 day ago

This is vehicle-to-load that requires a bi-directional inverter. They can totally do vehicle-to-grid without ANY hardware changes.

[–] flir 1 day ago

I think it's got V2H with lots of caveats (eg only on vehicles manufactured on or after October 1, 2026)

[–] IrishTechie 1 day ago

Have an older Model Y too. It’s a real bummer that Tesla decided to give up being the bleeding edge tech company. No V2L/V2H, no Apple CarPlay, no longer range leaders in their category (though still cheapest per km range).

[–] darknavi 1 day ago

> There's no hookup. The only power outlet is usb-c pd.

We have a 12v port that we can get ~200W out of, so that could power our internet.

But I agree, a real joke to have 150KwH (two EVs) in my garage and no way to even plug in a fridge.

V2H/V2L is a must have in my next EV.

[–] xg15 1 day ago

> The only power outlet is usb-c pd.

Don't give the USB consortium any ideas...

[–] ramses0 1 day ago

No association, but something like this is "the right answer", IMHO: https://www.cargenerator.com/pages/use-your-car-as-a-backup-...

1) if you're permanently modifying your home or electric panel you're over $1k. (General Motors "Vehicle2House" is ~$10-20k for hardware + installation... an EXTREME investment unless you plan on regular "emergency" usage of it)

2) if you're buying some portable solar panel "battery boom box" you'll likely run out and the folding solar panel it comes with is more gimmick than reliable

3) if you're buying a "real" gas/diesel generator, you have to run it + change the oil every 6 months otherwise it might not start in your emergency situation

...just buy a thing that clips to your car battery and dangles out the front hood of your car!

You already maintain your car every 3-9 months, you already (should) have at least 1/2 tank of gas at all times (especially in a weather / outage situation), you can generally idle your car for at least 2 days off a tank of gas in an emergency, and if this thing can charge your phone/battery packs, keep your fridge running (kindof?), and run a small space heater overnight...

It makes soooo much more sense to buy a $500-$1000 emergency accessory that piggybacks off the car you already maintain than trying to stand up a whole extra distribution mechanism for "survival-ish power, maybe 1-2 times over 3-4 years".

[–] mikestew 1 day ago

I don't think the residential power generator is needed anymore if you have an electric car.

As soon as we got the adapter for our Ioniq 5, I sold generator to a neighbor. The car will run what we need for four days, which is longer than the generator and five gallon can of gas is going to last.

[–] barbazoo 1 day ago

If you have an electric car that supports V2H.

Despite the dealer saying the used one I bought supported it, it turned out to not be available in the trim I got. My fault obviously for believing something a car dealer said.

[–] QuantumNomad_ 1 day ago

This thread is first time I hear about V2H. (I don’t have any car yet, electric or otherwise.)

It sounds amazing. Only thing I wonder if it can even be set up so that it will be like an Uninterruptible Power Supply. So that when there is a blackout, the V2H supplies all the power without any interruption.

I have several computers but no UPS yet. Imagine if I could buy an electric car and when I am not using it, my car is UPS for my whole house including my computers! :D

[–] masklinn 1 day ago

> It sounds amazing. Only thing I wonder if it can even be set up so that it will be like an Uninterruptible Power Supply. So that when there is a blackout, the V2H supplies all the power without any interruption.

That's the point of V2H (or a residential battery, which it emulates). Although you still want a UPS for computers: I doubt "without any interruption" is at the scale of a UPS, and possibly not at the scale a desktop computer will require. Notably it depends how the grids cuts off, if it cuts off in one shot (like throwing the breaker) the failover should be almost instantaneous, but if it fluctuates before failing the battery might need a lot longer to engage.

[–] sroussey 1 day ago

Yes, but you need specialized (expensive) equipment. Expect a $8-12k bill.

[–] QuantumNomad_ 16 hours ago

Will the setup outlive the car? Or will I have to replace it when I buy a new EV?

$10k amortized over 20 to 30 years is not too bad. But if I buy my first EV and only keep it for 5 to 8 years before replacing it with a different EV then I’m less happy if I also have to replace all of the additional equipment that soon.

[–] brohee 9 hours ago

It should be unrelated to the type of car. You need to automatically disconnect from the grid while feeding the home from the car, or you could cause great displeasure to the linemen working on repairing it.

V2H is pretty well standardized, there should be ways to avoue any car specific equipment.

[–] masklinn 1 day ago

V2L will also do the trick, although it's more annoying.

If power loss is a regular event you probably want V2H, but if it's just a remote fear or something that happens once every 5~10 then V2L and a few extension cords will do.