Historical Power Consumption SmartApp

This is probably a really easy thing, but I can’t seem to find an easy to way to track power consumption over a period of time. I’ve seen things like PlotWatt, but they seem a little beta, so I’m not sure if those are the best. Basically, I’m usually interested in seeing things like the total wattage something has pulled over the course of a day. Bonus points if I can see multiple days in some sort of chart. Any recommendations? This is fairly easy to do with something like a Kill-A-Watt–at least in a cumulative way–but I’m hoping ST can do something similar.

Other things you might want to look into include InitialState, Xively, and Grovestreams.

I’m doing this with a home-grown application stack (Graphite/Grafana/Backstop/Elasticsearch), which should probably also count as “a little beta”, but I’m throwing it out there for completeness. =)

Here’s a screenshot of mine:

What @btk said and Thingspeak. I use thingspeak.com to record watts and kwh with Aeon HEM v2. It just works. There are smartapps and device types out there. Search the forums.