All our hardware units are fully open-source and based on Arduino. 

Firmware sketches are available open-source on GitHub. See Resources for info on how to setup Arduino IDE.


All-in-one Unit 



Combined energy/temperature monitoring sensor node and web-connected Raspberry Pi base-station

Sensor Nodes

4CH wireless energy monitoring node 

emonTx V2 (old)

Only available as self-assembly kit

emonTx Shield

Arduino compatible energy monitoring shield


Low power temperature and humidity monitoring node


Available only as a through-hole kit.

Base Stations (emonBase)

Receives data from transmitter nodes and posts it to an emoncms server (local, remote, or both)

Note: The emonPi can also function as an emonBase, and is easier to setup using the built in LCD

Raspberry Pi emonBase

Raspberry Pi + RFM69Pi Receiver 

NanodeRF SMT (old)


Control Nodes 

WiFi MQTT Relay

ESP8266 WiFi connected 16A AC relay MQTT control unit


Software Modules


A powerful, open source web app for processing, logging and visualising energy, temperature and other environment data.

Firmware GitHub‚Äč

Arduino IDE compatible firmware sketches and compiled .hex files for hardware modules

All firmware and other software examples can be found on the OpenEnergyMonitor and Emoncms github.