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Comment by fukawi2 | Hacker News Reader

I got to tour the broadcast facility that transmits all the TV and Radio signals for Melbourne, AU. Part of their power infrastructure is a kinetic wheel - IIRC, 5 tons spinning constantly, that can put out 125kva for a few minutes - long enough for the backup generators to start up and take over. Damn impressive, and at least from a physics point of view, so simple too.

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I toured a couple old (early 2000s era) data centers that had similar flywheel backup power systems. Apparently it was a giant pain in the ass in practice as they had to regularly test it was still working by flipping the whole DC over to it briefly, and it was quite a nerve-wracking "this cannot fail, we have no other backup" moment every time. The thing needed constant maintenance as it's a mechanical beast with heavy load on bearings and such that eventually fail. The whole thing was eventually scrapped and newer DCs are just pure battery backup (+diesel generator) as I understand.

Backup generators need maintenance and may fail to start too, switching to batteries may fail too, I don't see how one can really remove the "maintaining and testing systems" overall.

Yeah you can test those systems in isolation though. For the flywheel system it had to be tested under real production load, basically flipping the giant switch to take the whole DC off the grid power.

You should see the flywheels at (the fusion energy research facility) JET. I haven’t, but they sound awe inspiring from the Wikipedia description. :)

What is the name of the broadcast facility so I can search for this?

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