Energy-behaviour anecdotes. In my local electrical store I have heard people told to look at energy efficiency ratings, and get the low-rated ones because they are cheaper. I know several people who put on appliances at night thinking they save money - although they are not on an Economy 7 tariff. And some businesses on an interruptible gas tariff found themselves unprepared when - you guessed it - the entirely predictable happened and there was an interruption.