E-Paper (4.2") solar box

thingiverse

Enclosures for the 4.2" e-ink display from Waveshare are powered by one 9 V solar panel. A horizontal and a vertical oriented version is possible, with the lid fitting both. A NodeMCU ESP8266 or ESP32 is powered by a 18650 3.7 V Li-ion battery which is charged by the solar panel on the box using a TP4056 charge protection board. This thing is kind of "work in progress" since I'm not sure if the panel will be able to power the NodeMCU/Display in the long run, but my similar box for the 2.9 inch display has been running for almost a year uninterrupted. The ESP8266 is put into deep-sleep mode to conserve energy and wakes up with regular intervals to update the info on the display. Parts list: - A 4"2 inch display (Three-color) - NodeMCU - Solar panel 9V - TP4056 Charge protection board - A 18650 Li-Ion battery - 1 diode. Note: I measured quite a difference in power consumption in deep-sleep between the various NodeMCU boards I've bought from various sellers. Up to 200 (!) times more power used in deep-sleep for the least efficient one compared to the most efficient. Code for displaying weather forecast can be found at Github, thanks to G6EJD for making it public.