Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface.

For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices:

https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete...

The information won't be as finely detailed since it's not sensing every circuit in the home, but for $70 and no tinkering necessary I can read my home's consumption in XML format every 10 seconds.

And even meters that don't have zigbee might be readable using an RTL-SDR. You do have to figure out which one is yours and which are your neighbors, though.

Pretty sure that the datastream is encrypted. Being able to sniff your neighbor's power consumption from far away is a pretty large security hole.

https://github.com/bemasher/rtlamr

I have not gotten around to figuring out which one is mine or a good way to system to store/display the data but I certainly can read the date.

In the grand scheme of things it is a minor to medium security flaw, power usage could be used to infer which houses contain valuable items and when people are home. I'd say medium at most since a lot of other things Visible curbside indicate this as well (lights, cars in the driveway, etc.). On the other hand, electronics are pretty efficient. A wealthy house with all the lights on is still using less electricity than a small apartment using an electric stove. But I guess if you were really interested in stealing electric cars then it would be really useful.