Hole in the wall

Back in the 1970's I visited the Police National Computer site at Hendon. In those days the PNC database was stored on large vertically mounted disks. I remember the manager who showed me around mentioning that they had put extra strengthening in the computer room walls in case the drive bearings failed.

As to this "latest" flywheel stuff a 30 second endurance is kind of limiting. I'd looked at their products once before and decided against them. I always assume that the generator will fail to start at the critical time and you need some time to initate a controlled load shedding and shutdown of critical servers. So a 30 minutes comfort zone is much easier for a commercial environment, well it would be if if you can cool the data centre as well.