Innovative CO2 Sensor Based on Cavity Ringdown

72273-The U.S. Department of Energy needs improved sensors to measure changes in the concentration of carbon dioxide in the atmosphere. Currently available instruments have high operational costs and do not meet the high precision and accuracy requirements. This project will develop carbon dioxide monitoring instruments based upon cavity ringdown spectroscopy. These instruments will utilize the self-calibration inherent to cavity ringdown spectroscopy to maintain better than 1 part in 3000 measurement precision during several months of unattended field operation. Phase I built a compact cavity ringdown spectrometer optimized for high sensitivity measurements of carbon dioxide. The instrument demonstrated a standard deviation of 1 part in 5800 over 117 hours of continuous measurements of 380 ppm carbon dioxide in air. Phase II will improve the cavity ringdown spectrometer performance to increase reliability, measurement speed, precision, and accuracy while reducing component costs. Prototype units will be built, tested, and delivered to field test sites to monitor carbon dioxide levels for extended time periods. Commercial Applications and Other Benefits as described by awardee: The carbon dioxide sensor platform should have application to research and government markets for carbon monoxide, carbon dioxide, and methane detection. The platform should also benefit industrial and agricultural applications.