Here is an energy dashboard that comes with an E Ink display and is designed to show the household power cost and consumption in real time. Designed by George Cave, the dashboard, as Hackster.io put it, is a step or two ahead of the traditional smart meters or apps that fail to show the complete picture when it comes to showing how much power is consumed and at what cost. The E Ink dashboard fills that void with more detailed information that, in Cave’s own words, shows all that is ‘happening behind the scenes’.
“I live in a house with solar power, battery storage, and an experimental energy tariff that adjusts with national demand,” Cave explains of the project. “The hardware and data are awesome, but most smart meters and apps do a terrible job at explaining what’s actually happening behind the scenes. So I built [my own]. Every fifteen minutes, this ePaper dashboard updates with real-time data from our household energy flow.”
The device that Cave developed uses a Waveshare 7.3-inch e-paper display capable of showing red, yellow, black, and white colors. The display has a resolution of 800 x 480, which, together with the 4-color support, should be adequate in displaying the entire energy scenario of the household with enough clarity.
The rest of the hardware comprises an Adafruit ESP32 Feather V2 that is connected to the Waveshare e-paper HAT via SPI. Though the size of the battery is not mentioned, one charge can let it function for months on end. The ESP-32 goes to work once every 15 minutes. All it does is fetch an image from the server, which is then rendered to the display. The same is repeated after 15 minutes again.
“I’m particularly proud of the peek-behind solar graph,” Cave writes of the dashboard’s appearance, developed after several months’ of data had already been gathered, “which renders the hidden outline of the solar in yellow on top of the daily load in red, to maximize the information density in only two-bit color.”
Visit Cave’s website for complete details on this.