Monitoring your home’s energy use is the best way to get a handle on your utility bills. After all, you can’t manage what you can’t measure! The only problem is that most home energy monitoring systems are cumbersome, complicated, or expensive. At least, until now. [Kevin] has created a new electricity meter based on Particle Photons which should alleviate all of these problems.
The Particle Photon (we get confused on the naming scheme but believe this the new version of what used to be called the Spark Core) is a WiFi-enabled development board. [Kevin] is using two, one to drive the display and one to monitor the electricity usage. This part is simple enough, each watt-hour is accompanied by a pulse of an LED on the meter which is picked up by a TLS257 light-to-voltage sensor. The display is a Nextion TFT HMI (touch screen) which is pretty well suited for this application. The data is corralled by emoncms, part of the OpenEnergyMonitor platform, which ties everything together.
For a project that has been done more than a few times, this one does a great job of keeping the price down while maintaining a great aesthetic. Make sure to check out the video below to see it in action.