Nathan R. Newbury, Ian Coddington, Ph.D., Kevin Cossel, Ph.D. and team

Millions of tons of methane gas are emitted every year during the production and transport of oil and natural gas, polluting the atmosphere and serving as a major contributor to global warming.

A team of physicists from the National Institute of Standards and Technology led by Nathan Newbury, Ian Coddington and Kevin Cossel have made significant inroads in tackling this serious environmental problem with the development of a pioneering technology to detect methane leaks as well as other greenhouse gas emissions.

Working with collaborators at the University of Colorado, this technology has been transferred to a startup company that has made enormous strides in expanding its capabilities and deploying the system in key oil and gas-producing states.

“The team’s system detects methane leaks with extreme sensitivity as small as one-quarter of a human breath at miles of distance,” said Melissa Midzor, chief of the Spectrum Technology and Research Division at NIST. “This technology has significant promise beyond methane detection since its enables simultaneous measurements of three airborne greenhouse gases—nitrous oxide, carbon dioxide and water vapor—plus the major air pollutants ozone and carbon monoxide.”

In the simplest terms, the technology—dual-frequency comb spectroscopy—shines an array of small, precise lasers through the atmosphere, each laser at a slightly different color or frequency. Where gases are present, they absorb only certain frequencies of light and the pattern of missing frequencies acts as a unique fingerprint revealing the presence and quantity of methane gas. Because laser beams can travel great distances, the technology can inspect large areas and simultaneously detect greenhouse gases as well as the major air pollutants.

The system builds on a Nobel Prize-winning innovation, the frequency comb, providing unprecedented control of and sensitivity to light across the optical and infrared spectrum.

After years of work by the team, this revolutionary laser system that originally took up an entire NIST lab can now fit into a small rack. Additionally, it can be constructed for a fraction of the original cost, which is key to enabling use in oil and gas fields, and in emerging monitoring applications.

While the potential uses of the technology are numerous, the first focus of the NIST team was methane, which constitutes about 20% of global greenhouse gas emissions and is 25 times more potent than carbon dioxide at trapping heat in the atmosphere.

“The technology is particularly important in connection with fracking,” said Greg Rieker, a professor at the University of Colorado, Boulder and the co-founder and chief technical officer at LongPath Technologies, Inc., which has commercialized the system.

Coddington said the system allows for continuous monitoring, which is important because a significant fraction of methane emitted from oil and gas fields comes from a small number of very large leaks. He said this allows oil and gas producers to quickly identify and prioritize repairs, reducing their emissions and improving safety.

Having this kind of data can help turn “highly contentious disagreements” into “a shared discussion” in which decisions and plans to address climate change can be made, said Marla Dowell, director of the NIST Communications Technology Laboratory and the NIST Boulder Laboratory.

“We can’t fix what we can’t measure,” Rieker added.

Besides its application to oil and gas production, Kristin Corwin, chief of the NIST’s Applied Physics Division, said the new system can detect nitrogen-based emissions in agricultural settings, monitor carbon and other pollutants in cities, and could identify chemicals that can be a signature for the illicit manufacturing of explosives or toxins.

“The great thing about this innovation is that it allows you to look at greenhouse gases and air emissions across a community,” Dowell said.

Cossel said he was motivated by “recognizing the methane detection problem, having an idea and finding a solution,” while Newbury said he and his colleagues operated with a sense of “openness and collaboration to create something very beneficial for industry and ultimately public health.”

“This is an instance of taking something that works in a controlled science lab and turning it into an incredibly practical tool that can be shared with the world,” Coddington said.

Midzor said the work of the team is really “a story of innovation and perseverance.”

“In less than a decade, this team took a Nobel prize-winning science experiment done in a lab in a highly controlled environment and converted it to an outdoor, robust measurement system that can help industry and improve safety and air quality for everyday Americans,” Midzor said.