Well, based on the 9 year / millions of dollars thing (and I agree this is a bit of a stretch), someone might say "Oh, hey, Jerry - are we paying $200,000 more this year for electricity than we did last year? Have prices changed? Not that much? Hm. Did we expand? We should look into this, I mean, that's a fair wedge of cash."

> How the fuck are the accoutants supposed to connect "big increases in electricity use" with "unauthorised installation of software on 5,000 school computers"?

Use common sense and ask people? Unless the school is doing something that requires that much electricity - it's probably reasonable to assume that it's the 5000+ devices that consume 300-1kw/hr of electricity.