I lived over the road from this building from the age of 4 'til 8 years old and saw it fully functioning. Oddly I did work experience there as a 15 year old and a week is a long time at that age and know the building inside and out. Weirdly I felt the urge to cycle there on Sunday and took a few photos (not the ones in the link). Then on Monday a work colleague showed me this link and it was a very eerie moment. I've always thought the building, since being empty (1995) would make an excellent setting for a horror / survival movie.
http://www.28dayslater.co.uk/forums/other-sites/82854-powergen-building-parkgate-shirley-birmingham-may-2013-a.html