It was much the same here at Metro Central Heights- no power, no security latches, dark corridors and stairwells and no water because the pumps weren't running. We do have emergency lighting but the batteries are only good for a few hours. Fortunately we have on site security.
It seems that it was possible to re-route power to some buildings but not others- our newer South and Vantage buildings had electricity by the evening but the older North, East and West blocks didn't. I guess they must be wired in to the grid in different places. Looking out towards the river there was a triangle of darkness between us, London Bridge and Tower Bridge.
Inconvenient though it was, if something goes so badly wrong with a critical piece of equipment that it requires 4 fire engines then it is not realistic to expect a fix within the hour. Working in production systems myself, I am sure that EDF were dealing with this major incident as fast as they possibly could.
Just to let you know, I was told that the reason things could not be fixed quickly was that asbestos was found when they were putting the fire out meaning that noone could enter the area until it was made safe - must've put a big delay on resolving it. Our power came back on at about 1.30 even though several blocks round us were on much earlier - differen circut I suppose!