Good thinking Paul,
It would not be the first time, that something like this has occured, maybe there might be a Cannabis Factory next door,don't laugh, the only way that these have been tracked down over here, is through their huge current draw on the mains.
Meter Readers, have "popped", a few of these places, with the continuously large unit readings between checks, they rang the Police, NZ$15,000 worth of Dope was found in the house, heaps of people went down over that one.
Couldn't have happened to nicer people,I say, and they got all they deserved too!.