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Comment by cjsuk | Hacker News Reader

To be fair people do test generators on a monthly schedule usually. Problem you find is it’s getting colder now so any problems are amplified suddenly. Might have been entirely tested a couple of weeks ago.

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Generators in critical situations like this are usually provided with crankcase heaters which keeps the oil at temperature and makes them easy to start. Also, any emergency power system should be (and usually is) tested monthly if only to prevent the fuel lines going bad.

Data centers can go down while testing the generators too.

There was a DC in California a few years back that had three generators fail during a scheduled test and one of their server rooms had a blackout because of it.

This is a very good point. In all the companies I've worked in we've had more UPS outages than line outages as well.

If your generators are not reliable in the cold, the issue is the placement of them. This is something basic to account for.

Yes and no. What the generator vendor says when they sell you the generator and what actually happens 5 years down the line are two different things.

The problem is usually not "not reliable in cold" but rather, the generators are X years old and the temperature is now changing in Europe from "mostly warm" to "warm over the day and icecold in the night" and finally aiming for "icecold all day", which means any equipment exposed will go through rather severe temperature changes.

While generators are usually able to handle this with sufficiently low failure risk, the risk is increase due to the changing temperature

It wasn't even freezing overnight at Strasbourg [1], I doubt that the cold could cause any effects at 5C. Maybe they were run once a month but never tested under load? 2x20kv lines failing will have put them at near maximum load immediately, perhaps they weren't designed for that.

[1] https://www.accuweather.com/en/fr/strasbourg/131836/daily-we...

Improbable. Even in a mostly-normal office building, the monthly generator test consisted essentially of "cut the mains power and see that no impact is perceived as UPS, batteries, and autostarted generators bear the load, in their turn for ~2 hrs total."

Europe sees that cycle every year, and have been for more than a century, so if they cannot handle that, they should be inside in a heated room.

Right, but that was obviously just an example.

Their generators are almost certainly tested frequently. But there could be any number of causes underlying the failure, and unfortunately sometimes failure does happen.

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