Hokey,
did you see these?
Piller DRUPS
They are the diesel rotary uninterruptable power supplies that they install (instead of millions of batteries)
Lovely bit of kit ... all of their data centres have them in multiples - cost a fortune, gotta be ordered months ahead, and worth every cent. Bit of fun when you first run them up - the 2000kg powerbridge spinning furiously ... "I hope the bearings are good, and she doesn't come out of that box" is the normal comment from sweating electricians (half of whom have fled to the other side of the building).
(20min delay)