Researchers at Linköping University in Sweden have developed an Arduino-based logger to measure levels of methane and carbon dioxide in greenhouse environments. The device also implements a DHT22 temperature and humidity sensor, data from which can be correlated with gas readings. Figures are stored on an SD card using an Adafruit data logging shield.

Importantly, the team’s study outlines a procedure for calibrating the methane sensor module at atmospheric concentrations, much lower than its normal use. The entire unit can be made for around €200, or about $235 USD. While an inexpensive method for monitoring CO2 has been available for some time, this fills in the need for a low-cost methane sensor that could be used for distributed measurements.

More information on the greenhouse gas logger can be found in the researchers’ paper.