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Comment by harg | Hacker News Reader

> with the capacity to produce up to 60 gigawatt hours of power per year

Maybe a nitpick but it's interesting how often people confuse power with energy/storage. "gigawatt hours" is a measure of energy, not power.

From my understanding Northvolt is manufacturing batteries, so the "60 gigawatt hours" figure is referring to amount of battery storage they're making. If they were generating power it could refer to how much energy they'll generate over a year, but I don't think that's what it is.

I think it's important to get these details right as it can change the meaning significantly

Also

> building a battery factory so large it would fill 100 football pitches and produce enough power to light 6bn light bulbs a year.

Is the factory generating power? How does the factory produce this much power? Or is it referring to the energy stored by batteries it's producing?

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It's not a nitpick. It's a question of whether a writer is scientifically literate enough to get that and many other details right.

I think the author(s) of the article is(are) just a tad sloppy. They also claim cobalt makes up to 20% of a lithium ion battery when the article they cite for that claim only speaks about the cathode.

Also, "lithium — the mineral that gives rechargeable batteries their superpowers" is a little bit too much hyperbole for my taste. Replace "rechargeable batteries" with "the current generation of batteries"...

Power is the wrong unit to measure battery manufacturing capacity in, but "per year" technically brings energy back to power.

It's important to realize that scientific terms don't really mean anything outside of science. Calling this power is like someone saying they have the flu, when they actually have a cold. It's wrong, but they weren't writing a scientific paper, they were just telling you why they stayed inside all weekend. It's important to understand that language is used that way, so you don't get too confused.

Yes, a lot of people say 'power' when they're talking about 'electricity' loosely.

Your point about "per year" technically going back to power is only applicable if you actually do the x GWh/per year maths. It's common to refer to energy production capacity as 'y kWh per year' (even though the ratio of those two components gives you the average power over that time period).

The medical terminology for "flu" is Influenza-like Illness or ILI. Under normal circumstances most ILI during winter is actually Influenza (you can randomly select patients experiencing "flu" into a study that checks if they have the Influenza virus), while most ILI during summer is not.

For most purposes knowing if it's actually Influenza isn't diagnostically important anyway, use medication to treat symptoms, stay home, rest, seek help if you don't feel better in a few days. Crazy how much of the world doesn't make this trivial for all residents - not just the US, but even many countries with some type of mandatory "sick leave" policy don't actually give all workers full pay to stay home with flu - encouraging them to instead go to work and get more people sick. And this normalises associated social expectations which also have negative consequences. If I work when I'm sick, why wouldn't I go to a bar, or visit friends?

Having to do mental gymnastics to understand somebody using wrong words is one thing. Not everybody has to know better.

Writing about a subject with completely wrong terminology/concepts and thus severely miseducating people is another. I can already hear people claiming all batteries are based on Lithium and contain 20% Cobalt.

No.

My car use is about 10000 km/year. That does not mean it’s a velocity.

It would be a speed, not a velocity, because velocity is a vector not a scalar. Something like "10000 km/year in a north east direction" is a velocity.

But with that corrected, 10000 km/year certainly is a speed; it's just an average speed rather than an instantaneous speed.

No.

It’s car use accumulated over a year. It is not an average speed.

I don’t agree that there is a wide consensus that velocity must be a vector outside of physics where it actually matters. “High velocity” is a term that does not hinge on a vector being present somehow.

Not only, IF it was a speed (it isn't) it would be a very, very slow one, as 10,000/(365x24)= 1.14 km/h.

Yes right, and a completely meaningless quantity without saying it’s the average /over a year/, so the accumulation interval is essential - thus cannot be thought of as a speed or velocity.

It's definitely average speed over a year.

High velocity refers to the magnitude of a vector beyond 2D, so there is no conflict here.

Calling another virus infection flu isn't actually wrong anyways. The word has been used that way for centuries before we actually were able to identify the virus.

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