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points by masklinn 1 day ago | 0 comments
Also very important: the cybertruck is not the only vehicle capable of doing that (the keywords are V2H and V2L, V2H is the more convenient — the car just plugs into the mains and acts as a house battery — while V2L means you have to go and plug your stuff to the car's mains outputs directly)

> Most of the disasters I'm aware of people either get their power back in a short enough amount of time that they can use a normal generator for the gap

TBF an EV car has an absolutely massive battery relative to the electric consumption of a house, unless you're using resistive heating all around. Especially if you ration use.

[–] jayknight 1 day ago
Here's Alex from Technology Connections testing powering things in his house from his Hyundai Ioniq 5.

https://youtu.be/yO5fJ8z66Z8

[–] anthomtb 1 day ago
I live in an area prone to high winds and we occasionally have pre-planned power shutdowns (I think PSPS is the term).

My Ioniq 5 has been a godsend. No, it can't power the house without dorking around with my electrical panel. But we can run the fridge, dishwasher, a few standing lights and keep phones and computers full charged.

I used a similar setup to Alex's but with the outlet in the rear seat instead of the V2X connector. I will probably by the V2X connector since it supposedly hanldles higher power draw.

[–] greggsy 19 hours ago
I can’t imagine using a dishwasher with limited power?
[–] anthomtb 7 hours ago
That was my initial thought. But after 18 hours of running lights and fridge the car still had over 90% charge. So I saved myself the hassle of hand washing.
[–] tedggh 18 hours ago
I barely use mine with unlimited power. Unless I’m hosting dinner for 20.
[–] pipe2devnull 18 hours ago
It’s only me and my partner and we run it every single day. To be fair we both work from home so we generate more dishes than two people that go to work I suppose but I just hate doing them by hand
[–] jebarker 17 hours ago
You don’t have to make excuses, modern dishwashers are really water and power efficient.
[–] londons_explore 14 hours ago
A European model uses about 1 kWh for washing 12 place-settings (big plate, small plate, bowl, saucer, glass, mug).

US models approx 2-3 kWh because energy efficiency laws are nowhere near as strict, and they use hot fill of usually electrically heated water.

[–] debatem1 15 hours ago
I think a really in-depth look at how people use dishwashers would be pretty interesting. There are a lot of surprisingly strong opinions about right ways to do it. Of course knowing the right way is also interesting, but how people came to be so convinced that their way was the right way would be even more interesting to me-- I suspect there are a lot of hidden generational and socioeconomic attitudes hidden in there.
[–] ghaff 13 hours ago
>suspect there are a lot of hidden generational and socioeconomic attitudes hidden in there

You're probably right about that. A lot of people grew up without dishwashers and don't have a way to economically install one outside of a major kitchen remodel even if they have the space which many in cities don't have. They're also not the, for lack of a better term, necessities that washers, stoves, and ovens are. And, of course, dishwashers don't eliminate the need for any handwashing and if you aren't cooking or doing a lot of entertaining a lot, they may not be all that useful. I do cook but still probably only run my dishwasher 2 or 3 times per week.

[–] ludicrousdispla 14 hours ago
I was going to make a joke about ludicrous speed, but then remembered that automatic dishwashers for restaurants typically clean dishes in under two minutes.
[–] cachius 1 day ago
Is that the new PlayStation?
[–] maartenh 20 hours ago
TIL about his extra's channel, thanks!
[–] manmal 1 day ago
We have a heat pump with SOCP 5, but are still using 30kWh per day now.
[–] masklinn 1 day ago
That's 2-3 days worth without changing your use pattern, which surely you would do if you expected a long blackout period?
[–] zeeveener 1 day ago
On most modern EVs, that's at least 3 days worth of power if the vehicle is not being driven. Larger vehicles naturally have far larger batteries.
[–] darkwater 1 day ago
Mmmh no? 90kWh battery packs are not that common. An M3 or MY LR AWD have an 82kWh. Some Mercedes and some Chinese model have a 100+kWh battery but the most common setup is between 60 and 70.

Anyway I agree that in emergency conditions it can go a looong way for a house.

[–] sroussey 1 day ago
My bmw has 108
[–] pmontra 1 day ago
Is that 30 kW each hour of the day or 30 kW per day?
[–] alex43578 1 day ago
30 kWh per day, while a clunky unit, is what most people would understand when talking about home consumption. It’ll be what their utility typically reports, how you’d want to size a battery, etc.
[–] gertrunde 1 day ago
Sort of neither?

It's 30kW for one hour.

(Or 1.25kW for 24 hours, or however you prefer).

[Link: https://en.wikipedia.org/wiki/Kilowatt-hour]

[–] numpad0 1 day ago
It's like you had a faucet with cross section of 2 square inches, and 15 seconds with that faucet wide open would fill a jug. That jug holds 30 squareinches-seconds of water.

You may then use that water over the course of a day. That's 30 sqin-sec per day. That is not 30 square inches for a whole day. It's second per day.

Or watt hour per week or whatever.

Yes, it can be described like 0.00034722 sqin/day, and that corresponds to no physical object and that would be largely useless.

Why not Joules or Liters? Because that's complicated for anything electrical.

[–] OJFord 1 day ago
Pretty sure GP understands that, their point being you can't just wave away 'per unit time' when talking about it relative to generation, it matters.
[–] buran77 1 day ago
"30kW per day" makes no sense. It's like saying "100km/h per day". W is a unit of power, Wh is a unit of energy.

It's unintuitive because a guy named Watt decided "Joule per second" is Watt, so the intuitive units Joule and Joule per second got turned on their head to W times hour and Watt. This is opposite to usual intuition of distance and speed for example, km and km/h. If I redefined the km/h to a "tick", then a km would become "tick times hour".

If you want a "better than nothing" but imperfect analogy, Wh is how much water you have in a bottle, and W is how quickly you can get the water out.

[–] LtdJorge 1 day ago
The naming of the unit is posthumous
[–] OJFord 10 hours ago
Where are you getting "30kW per day" from?
[–] ffsm8 18 hours ago
And yet all utilities of the world decided to use kWh as the thing to measure. Also basically all smart measurement devices settled on this being the default to show. Exactly in the way he used it here, kw per day, kw per week, kw per month, kw per year.

This discussion seems super silly, considering he's just using the measurement that the industry adopted decades ago...

Are y'all just coming out of a time travel device from the 70s or something?

[–] buran77 12 hours ago
> Are y'all just coming out of a time travel device from the 70s or something?

I'll put aside the two-bit attitude and that you don't know that power (W) and energy (Wh) were measured in the exact same way in the "70s or something" (just ask your grandparents).

> the world decided to use kWh as the thing to measure

> kw per day, kw per week, kw per month, kw per year.

There is no such thing as "kw per day". You switched between units from one sentence to the next? The world indeed measures kWh per day, not kW per day. The lazy use kW per day as a shorthand and drop the "hour" to speak faster. The less educated measure "kW/day" because they don't understand the concepts and just parrot a common mistake. When they say "kW/day" what they should actually say is "kWh/day". It's where the unintuitive part comes in, they omit the "hour" or assume kWh is the same as kW/h, like km/h, instead of kW times h.

> This discussion seems super silly, considering he's just using the measurement that the industry adopted decades ago...

The industry adopted the correct measurement units decades before your grandparents were born. You just have a hard time understanding because it's easier to do cheap snark.

Unlike those people from the 70s or something, y'all live in a world with all the information you could want at your fingertips, you even have machines (AI) that digest it for you, and you even had me bothering to give an explanation a kid could process. To be unapologetically ignorant today is the same as being intellectually incompetent, ffsm8.

[–] SamBam 1 day ago
"30kWh per day" isn't waving away anything.

30kW is a rate.

30kWh is a measure of energy, about 100MJ.

30kWh/day is a rate again, 100MJ/day.

It seems clunky, but it's a way energy usage in a house is typically measured.

[–] OJFord 9 hours ago
Thanks, I went to school too.

I said the time period matters when you're talking about it relative to generation. 30kWh over the course of a day is very different to 30kWh over ten minutes.

[–] SamBam 3 hours ago
Um... My reply was to you saying "I'm sure GP understands that [explanation]"

Except that GP (pmontra) had asked "Is that 30 kW each hour of the day?"

Clearly someone asking that doesn't understand what kWh/day means, and since you were backing GP, it seemed reasonable to guess that you might not understand either.

[–] stavros 21 hours ago
Wh is a unit of energy. They're saying how much energy they consume per day.
[–] OJFord 9 hours ago
And I'm saying how much energy you use 'per day' is vague when you're talking about it wrt your energy generation. If you have 30kW solar and no battery then 'all my usage is during peak sun' and 'all my usage is over a split second at 1am' and 'my usage is uniform across 24h', etc. are all very different even if all amount to 30kWh usage 'per day'.
[–] imtringued 21 hours ago
No, their point is wrong either way and there is no way to steel man it without saying the comment is extremely poorly articulated.

30kWh is 1.25kW for 24 hours or 30kW for one hour.

30kW every hour means 720kWh per day. 30kW all day is also 720kWh per day.

The comment is nonsense.

The only way you can steel man it is by saying he isn't concerned about the 1.25kW, he is concerned about the swings, but he said 30kW twice for two different time spans so that can't be it either.

[–] tdhz77 1 day ago
As soon as the Rivian has v2h I will buy
[–] harikb 1 day ago
The value of a used 24 KWh battery used in, say, an old EV non-tesla car - $2000 (note this still has plenty of life left). Example: a 2013 Nissan Leaf

The value of the same, repurposed to a "powerwall" - $10k per 10 KWh

The value of it once attached to a "movable powerwall" - :) add a few more zeros

Clearly, I am in the wrong business...

[–] alex43578 1 day ago
You can get good batteries for a lot cheaper than a power wall. Just like when the Tesla family of companies tried to do home solar - big premium for the name.
[–] lostlogin 1 day ago
This puzzles me.

When we got solar we asked for quotes, but ‘No Tesla’. The sales rep said ‘We get that a lot’.

[–] Lio 23 hours ago
Haha, I’m actually in process of installing a home solar setup. That’s exactly what I told the installers too.

I wasn’t interested in hearing any advantages of a Tesla Powerwall, that brand is toxic to me now.

There’s plenty of good alternatives that don’t fund criminals like Tommy Robinson and Russell Brand.

[–] lostlogin 23 hours ago
What did you go with?

We have Sigenergy. Are they better than Teslas? Unsure, but at least I have no idea what the owner(s) think.

[–] Lio 13 hours ago
Nothing is installed yet but I think the plan is to go with Sunsynk. It's still being debated though.

I want a system that doesn't need to be connected to the cloud.

[–] wlesieutre 1 day ago
I knew a guy with a Tesla solar system and his advice was also “no Tesla”
[–] amscanne 13 hours ago
Like what?

If you have a string inverter setup, I’m not aware of anything good that is cheaper. If you have micro inverters then sure, but otherwise you have additional hardware cost.

[–] trainsarebetter 10 hours ago
Pair a used ev battery with the battery emulator https://dalathegreat.github.io/Battery-Emulator-Wiki/

And you got a budget opensorce powerwall

[–] throwaway85825 1 day ago
Batteries are cheap, an unsafe installation burning your house down, extremely expensive.

Best practice would be to build a separate structure and physically separate the battery from your house.