I was once taken on a guided tour of the Windscale nuclear power electricity generator in Cumbria circa 1989 (it is something they used to do free on appointment as a sort of PR exercise, I suppose). One thing that really surprised me was this:
We passed a man sat in front of a row of dials. We were told that part of his job was to decide how much energy output would be needed at different times of the day. He had with him a copy of the Radio Times. He told us that whenever a popular TV show came on he would increase the amount of output needed simply by moving a dial up a few notches. He had highlighted the shows that he felt would be popular in advance for this purpose. If I remember rightly, there was a show about Princess Diana in that tevening that had been marked out.
I'm sure I didn't dream all this!