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.
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.
Keep in mind that a traditional 100 amp service for the house can theoretically provide 100 amps * 240 volts == 24,000 watts == 24 kilowatts, instantaneously. You multiply by 240V because you have two input legs, each providing 120V service to ground, on separate phases.
That’s why whole-home generators are typically sized at 24kW, unless there are some circuits you’re not going to power while you are operating on generator.
Now, most homes don’t use that much power 24x7. Most homes use a lot less than that. But, they need to provide that much power, in case all the electric devices inside the house are all running at the same time. And in Texas, newer homes usually come with 200 amp service, because HVAC draws so much, plus electric hot water, electric cooktops, etc….
So, to get a real idea of the amount of power you need from batteries, you need to look at how much power your house actually requires on those critical circuits, on the worst day. If you can’t deliver that much peak power, then you need to increase the size of your inverter stack, or you need to reduce the number of critical circuits you’re powering. Most battery solutions for powering a house will give you some options here, and then combine all the output power from each stack into a smart breaker box.
Then you also need to look at how much total power you pull over a full day. That’s your minimum kWh rating that you need from the battery pack. And again, most whole-home type battery solutions will give you multiple options here. These are companies like Bluetti, Anker, EcoFlow, etc….
For example, the Anker SOLIX E10 Power Dock can do a max of 7.6kW sustained and 10kW turbo output with 12kWh-90kWh storage, depending on how many battery units you connect to that inverter. But to get 20kW total turbo output, you’d need two inverter stacks, each with their own chain of batteries. And you would need their Smart Power Dock to combine those two stacks. Each power dock can handle a total of three input stacks, for a total maximum of 22.8kW combined max sustained output, with 30kW combined turbo output. That gets you their 200-amp equivalent service.
In comparison a Tesla Powerwall does about 11.5kW maximum output for one unit, but has much less battery capacity per unit (only 13.5kWh). And you would either need to trim down your critical loads to get under that 11.5kW maximum output, or have a pair of such units that each talk to their gateway device. And the Tesla Powerwall doesn’t have any additional battery units that I know of that you can connect to that same inverter. So, you would end up buying a lot more inverters if you want longer runtimes with Tesla.
Either way, you can pair these with solar panels on your roof, to get either total or partial fill of these units from the sun, and the rest from the grid. The same is true for all of the major whole-house battery backup units I know of.
Now, if the batteries in your car can sustain 100kWh of power, and you’re using 30kWh per day, that would last you just over three days before you’re completely drained. Then you would have to look at the maximum amount of instantaneous power that the vehicle can provide. Is that just 10kW? Can it do 20kW? 30kW? Note that this number is usually a lot lower than the rate that the vehicle can charge at, when it is at a supercharger facility. Usually, they can suck down the power a lot faster than they can push it up. And many BEVs today are still pretty slow at being charged up.
I look forward to the day when all BEVs can charge quickly at high voltage, and also discharge V2L and V2H at high rates of speed, with large battery capacities. But I think it’s going to be a while before we get there.
Meanwhile, I feel like I need to have the power service at my house upgraded to 200 amp, before I can realistically buy a BEV. We just don’t have the spare power capacity available to us to be able to charge the vehicle at reasonable speeds, which would require a level 2 charger at home.
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.
"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.
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?
> 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.
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.
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.
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'.
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.
You don’t need user consent to retain data that’s arguably needed to provide the service itself. I guess, safety falls into that category. Training on that data is probably a grey area, if they can guarantee it won’t contain PII. They have stolen all the internet, so I wouldn’t bet highly on their restraint.
It's very easy to prove that training is not necessary to provide the service, because whenever you're using a model it's static and the training only maybe goes into new models.
That’s legacy code, not technical debt. BTW. If you leave the company, who will understand your code though? Institutional knowledge always fades away eventually.
Technical debt is something that hinders the ability to understand the code and how changes will impact the code. A hypothetical technical debt-free piece of legacy code could be picked up by a new developer and they'd understand it perfectly after reading it.
> Why would the body, a master of efficiency, produce IgE just for fun?
I was being punchy. “The pathway of B cell differentiation with respect to the nature and location of potential IgE+ memory cells as well as long-lived IgE producing plasma cells in allergy is still not completely understood” [1]. We do know, however, that “IgE is continuously produced to maintain constant IgE levels in blood,” and that Th2 cells can increase that baseline.
they are saying that the body produced to to fight parasites like worms. these were a big problem for most of evolutionary history. With modern living standards, our immune systems don't encounter many parasites so they get "bored" and over react to harmless things like food. Evolution hasn't had time to adjust to the new living standards since its only been a few generations.
I'm from Eastern Europe and I don't think I know a single person with allergies. As someone who live outside of it, I can say people are a bit lax with hygiene here except when cooking meat. People can't reconcile you can eat medium rare steak.
Luckily you don't need to be infected by parasites to have a good immune system. What seems to work best is exposure to bacteria and viruses and fungi and parasites that don't infect humans. Things associated with other plants and animals. The immune system learns better from the things that it is effective at protecting you from than the things that outsmart it. So let's not bring back the human parasites.
“When Jasper Lawrence learned that hookworms might lessen the effects of his allergies, he set out on a unique mission: To travel to West Africa and purposefully become infected with the parasite” [1].
Would you rather ancient issues to which our bodies have apparently adapted or new issues we haven't yet had time to adapt to? I'm not sure on the answer myself but it doesn't appear as clear cut as no worms => no issues.
You don't have to give worms to everybody. If healthy adults would be better off with worms (and that's a big if) you could infect just adults. And then give them worming pills in late middle age when their immune systems are weakening.
Why select over generations when you can fix things directly? That's what medicine should be focusing on. Ways to safely edit our genes, metabolism and immune systems. Growing new body parts to replace broken ones.
All of this being used in practice might be more than 50 years away but there is no biological reason why it should be impossible. Just a lot of work, too much for any single company or government. It will take global coordination, massive investments and maybe the end of capitalism but I think we can pull it off as a civilization.
Why not use gherkin given/when/then stories, and build E2E runners and maybe also unit tests for them? I don’t understand why a new spec format is necessary, which forever binds you to using agents for evaluation. Deterministic tests also have the advantage that they are harder to cheat on. If they are green, they give me a strong signal I can trust.
Tests can be green and I think doing E2E is better than just unit tests. But it's also very easy to have hundreds of tests that are green - but if they are testing the wrong thing then it really doesn't matter.
Ultimately, you spec out these tests and create deterministic code around them - but that doesn't mean that the tests didn't drift from the intended spec.
I think I agree with the author in that what you were TRYING to achieve is much more important than what you actually achieved (in code or tests) and actually using the product is your best defense to see if code / spec has drifted.
But good gherkin tests encode pretty well what I’m trying to achieve, because they can be super high level - any flight level I want them to be. The only precondition is that the test env can deterministically measure the conditions.
Yes it’s basically unlivable. It’s super small and way too many people want in, every day. It’s also a very beautiful spot and I sometimes crave going to that wider area (Salzkammergut).
The German Wikipedia article on Salzburg (https://de.wikipedia.org/wiki/Salzburg#Namensgebung) has an extensive section on the name. It mentions that salt mining in Hallein only started when Salzburg already had its name, so the name is either connected to Reichenhall or derived from the river Salzach on which it's located. Despite the area being undeniably salty, Salzburg itself didn't have a salt mine or play an important role in the salt trade.
Sure but that’s probably 100x max? It won’t magically work, there’s a lot of (auto) review and verification that has to be carefully setup, so things actually work in the way you need them to. I’ve done it, it takes days until it’s good.
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