Field inter-comparison of low-cost sensors for monitoring methane emissions from oil and gas production operations

Four solar-powered methane sensing systems with remote communication capabilities were tested for nine months at an oil and gas production site in west Texas. Sensor performance was evaluated using single blind certified gas challenges and by comparison with a continuously operated quantum cascade tunable infrared laser differential absorption spectrometer (QC-TILDAS) system. Dispersion modelling was used to estimate concentrations that would need to be detected to identify continuous and intermittent emission rates of 5–10 kg/hr from oil and gas production sites within ~50–100 m of the sensors, and these concentration thresholds were used in establishing performance criteria for the sensors. The four sensors demonstrated sufficient precision to allow for detection of emission rates of 5–10 kg/hr and had data capture rates that exceeded 80 % during the 9 months of operation. One sensor had a 100 % data capture rate, despite severe weather conditions and extended local electrical power losses. These results demonstrate that multiple commercially available sensing systems are suitable for long term methane emission monitoring in remote oil and gas production regions.