Breakthrough in Methane Gas Detection and Quantification

Scientists at the Chinese Academy of Sciences have developed a non-cooperative target-based, low-cost active standoff gas sensor for imaging and quantifying methane (CH4) leaks. The sensor, based on tunable diode laser absorption spectroscopy (TDLAS), measures the path-integrated concentration of atmospheric CH4 with high accuracy. The research, funded by the High-Resolution Imaging Spectrometer (HRIS) Technology and Equipment and Key Technologies and Equipment for Ocean Sensors, demonstrates the sensor's potential for application in the natural gas industry.

Key Takeaways:

  • The developed sensor can detect CH4 leaks down to 0.1 g/s at 30 m range and quantify leaks with accuracy better than 10% at 10 m range.
  • The sensor uses tunable diode laser absorption spectroscopy (TDLAS) to measure the path-integrated concentration of atmospheric CH4.
  • The wavelength modulation spectroscopy with first harmonic normalized second harmonic detection (WMS-2f/1f) method is applied to reduce measurement errors.
  • The sensor is integrated with a pan-tilt unit, a laser rangefinder, and a visible camera for 2D scanning and imaging.
  • The CH4 concentration data, ranging data, and pan-tilt angular data are fused to generate a pseudo-color map of CH4 concentration.
  • The CH4 leakage rate is estimated by a mass balance algorithm based on the wind speed data collected by an anemometer.
  • The research has been peer-reviewed and published in the journal Sensors and Actuators B: Chemical.

Statistics:

  • 0.1 g/s: the minimum CH4 leak detection limit of the sensor at 30 m range.
  • 10%: the accuracy of CH4 leak quantification by the sensor at 10 m range.
  • 30 m: the range at which CH4 leaks can be detected by the sensor.
  • 10 m: the range at which CH4 leaks can be quantified by the sensor with high accuracy.
  • 2025: the year in which the research was published.

Sources:

  • Active Methane Gas Imaging and Leakage Quantification Based On Standoff Tdlas and Pan-tilt Units. Sensors and Actuators B: Chemical, 2025;436.
  • NewsRx. Data on Energy Detailed by Researchers at Chinese Academy of Sciences (Active Methane Gas Imaging and Leakage Quantification Based On Standoff Tdlas and Pan-tilt Units). Energy Weekly News. August 8, 2025; p 67.