Energy efficient planar catalytic sensor for methane measurement

► The transition from traditional catalytic bead sensors to a planar sensor design. ► The use of free edge alumina membranes to support the catalytic sensor. ► The use of a single sensor for reliable gas detection instead of the traditional Wheatstone bridge circuit which involves two sensors. ► Sensor operation in a pulsed regime. We present results on research and development of catalytic sensors fabricated by planar technology on anodic alumina membranes. A method to detect methane was developed which prevents humidity from affecting the sensor performance and, at the same time, reduces energy consumption. The method, based on step heating the sensor during measurements, enables the power consumption of the sensor to decrease from 35mW typical of the conventional measurement method to 1.2mW. As a result, a wireless sensor node equipped with a planar sensor and powered by three AA batteries could operate for about one year.