If you really want to know what is going on with the power in your house the only way to be sure is to monitor it.
There are many systems available out there, but it wouldn't be a JAW project if I didn't attempt it myself! This system is based on the Arduino microprocessor system which is a great open source piece of hardware. It is based on existing energy monitoring libraries, and several other great libraries for things like web interfaces, Modbus interface (an industrial communications protocol) and an ethernet interface for "The Internet Of Things".
I installed CTs on all the circuit breakers in my house for full energy monitoring, nothing escapes my web. The plots you see in these pages were gathered by Citect, an industrial HMI interface that I use in my day job, but I'm thinking of an Android based app to do the job.
Very much a project under construction, my apologies, there will be full disclosure and instructions on building it yourself in due course.