When I worked at what was then Inland Steel (Indiana, US) they had a coal fired 60 Hz power station. It did not produce all of their power but it did produce a

When I worked at what was then Inland Steel (Indiana, US) they had a coal fired 60 Hz power station. It did not produce all of their power but it did produce a significant amount. The reason it was there was that they could use steam after it had passed through a portion of the turbine for other plant processes. Chip fabs are in a different situation. My understanding (and I am far from an expert) is that typical power interruptions such as the momentary loss when a breaker trips and recloses will interrupt production. A quarter second might as well be 30 minutes as it will cause all motor controllers to drop out. Chip fabs need something akin to a giant UPS (or alternative power feed that they can switch to in a few milliseconds. Such equipment exists and is costly. The business case is the cost of the power conditioning vs. the expected lost production due to potential outages. Perhaps Samsung did have something that could ride out a short outage but not the one they faced. In that case there is a vast difference between 1/4 second drop and a 30 minute outage.