Solar LoRa Sensor Node for Far Fields
Send soil and weather readings kilometers away on a tiny battery recharged by the sun.
Wi-Fi reaches across a house; LoRa reaches across a farm. Low-power radios plus deep sleep let a sensor node run for months on a small solar panel.
Video tutorial
Video by Davy Wybiral, embedded from YouTube. The written steps below are our own and match the parts list.
Mission steps
Pick the band
Use 915 MHz modules in the Americas (868 MHz in Europe). It is license-free ISM spectrum with power and duty limits built into good libraries.
Wire the radio
Connect the LoRa module to the ESP32's SPI pins plus its reset, busy/DIO pins as the module's library documents.
Sleep between readings
Wake every 15 minutes, read sensors, send one short packet, go back to deep sleep.
Build the gateway
A second ESP32 + LoRa (or a Pi with a LoRa HAT) receives packets and forwards them to MQTT or Home Assistant.
Add solar
A 6 V panel with a lithium charge board keeps an 18650 cell topped up. Mount it facing south (north in the southern hemisphere).
Questions
How far does LoRa reach?
From a few hundred meters in dense neighborhoods to several kilometers with line of sight and a raised antenna.