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Comment by fastball | Hacker News Reader

TFA says 100MW, not MWh. So it's not clear if this is the maximum discharge rate or the actual storage capacity.

Side note – I don't think I'll ever stop being annoyed that we use Wh instead of J for things like this, very confusing to people and makes conversions harder.

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Actually the article does say that the 100MW is served for about an hour that makes it 100MWh. But I do agree that it is a sloppy journaism to confuse power and energy. Basic high school level physics.

That was in reference to their Australian installation, not this new Texas one.

It makes a lot of sense to specify energy in Wh in electrical engineering. It's much easier to convert to other useful measurements involving volts, amps, and watts than joules are.

>It makes a lot of sense to specify energy in Wh in electrical engineering. It's much easier to convert to other useful measurements involving volts, amps, and watts than joules are.

Easier how? A watt-hour is just 3600 joules - the number of seconds in an hour.

1 joule = 1 volt * 1 amp * 1 second

1 watt-hour = 1 volt * 1 amp * 3600 seconds

Thanks, I can't believe I've never realized that Wh and J are measuring the same thing!

Just to be clear 1 Wh is not 1 J.

3600J = 1 Wh.

Yes, a J is technically a Ws (watt-second).

Or more accurately, since Joules are the fundamental unit and Watts are a derived unit, a Watt is a J/s (Joule per second)

Damn. Never made that connection. Have a upboat

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