Monitor energy usage over a month?

Any device that provides energy metering capabilities will provide you data, BUT they don’t “store” data. GE’s Zigbee wall plugs are good devices and report energy very often vs. just every 5 minutes or so. In fact, any Zigbee metering switch reports energy usage immediately vs most of the zwave devices available today (without a custom DTH). There are reasons why, but that’s a separate topic…

Anyway, those sophisticated solutions are the only way to get what you want for monthly usage analysis. I think the simplest solution would be to send data to Google Sheets via this SmartApp: