Researchers at Colorado State University are completing work on a $3.5 million award from the Department of Energy’s Advanced Research Projects Agency – Energy (ARPA-E) program to design, build, and operate a facility that simulates natural gas production sites under real-world industry conditions. The Methane Emissions Test and Evaluation Center (METEC) is being used to test the performance of low-cost methane sensing technologies for locating and characterizing leakages from equipment both above and below ground.
Getting natural gas out of the ground and to the consumer is a complex process during which about 2% of the produced methane is lost through leaks, although emissions are highly variable site to site. In addition to economic incentives to reducing losses, methane, the main constituent of natural gas, is a potent greenhouse gas. Existing methane monitoring devices have limited ability to cost-effectively, consistently, and precisely locate and quantify the rate of a leak.
Dan Zimmerle, a senior research associate at CSU’s Energy Institute and principal investigator of the METEC project, notes that the technologies being tested at METEC “represent breakthroughs in what’s possible in methane sensing. Some of the solutions are the equivalent of a $20,000 instrument reduced to a $500 package. Our job is to assist in bringing these technologies to market.”
CSU researchers are well known for their expertise in methane emissions research, conducting over $11.7 million of work in the past five years under funding from Environmental Defense Fund, the Department of Energy, industry, and state and local communities. Zimmerle’s METEC co-principal investigator is Anthony Marchese, professor of mechanical engineering and associate dean for academic and student affairs in the Walter Scott, Jr. College of Engineering. Contributors to METEC and earlier projects include Jeffrey Collett, Jr. (atmospheric science), Jeffrey Pierce (atmospheric science), Azer Yalin (mechanical engineering), Bryan Willson (mechanical engineering and director of the Energy Institute), Jay Ham (soil and crop sciences), and Joe von Fischer (biology).
Fred Krupp from the Environmental Defense Fund noted, “CSU has some of the best people in the world who know how to measure methane. CSU is unique in that it’s led several of our studies, and we’re so appreciative of their good work.”
Methane emissions inventories
Marchese led a recently completed first-ever national study on methane emissions from natural gas gathering facilities and processing plants. Although processing plants are required to report methane emissions under EPA’s Greenhouse Gas Reporting Program, little information existed on the emissions from gathering facilities. Marchese’s study found that methane emissions from natural gas gathering operations were under-represented by a factor of eight in the U.S. Environmental Protection Agency Greenhouse Gas Inventory. The 2016 update to the inventory, incorporating CSU’s findings, raised the contributions from this sector to nearly 30 percent of the total methane emissions in the U.S.
Marchese has recently teamed with Zimmerle on a follow-on $1.8 million DOE-funded study of natural gas gathering compressor stations and individual compressor units that is now underway, and that will analyze contributions from individual components within these stations to better understand the sources of emissions. Their goal is to build a national model for methane emissions that accounts for the mix of station types and activities.
AIR QUALITY STUDIES
Natural gas leaks are also a concern when it comes to local air quality. Collett, professor and head of the Department of Atmospheric Science, recently completed two major Colorado studies characterizing air emissions from oil and gas production as well as from new drilling and completions (hydraulic fracturing (“fracking”) and flowback). Using innovative strategies for measurement of emission plumes, they quantified emission rates and dispersion of air toxics, ozone precursors and greenhouse gases during each of these processes. A $1.7 million study was completed in Garfield County in the Piceance Basin in western Colorado under support from Garfield County and several industry partners. The Colorado Department of Public Health and Environment supported a $1.2 million study in the Denver-Julesburg Basin on the Colorado Front Range, with major oil and gas producers providing site access for emission measurements.
These two companion studies represent the most comprehensive assessment of air toxics, ozone precursor, and greenhouse gas emission rates from natural gas well drilling and completion operations to date. The largest emissions of methane and air toxics were typically observed during well flowback, an activity following well fracking when injected frack fluids and produced water are removed from the well. Emissions data from the two studies form the basis for a major ongoing study sponsored by the State of Colorado to assess potential health risks associated with living or working near oil and gas development. In separate efforts, Collett and his group have also studied impacts of increased oil and gas development on the formation of fine particle haze in Wyoming and North Dakota.
“CSU has some of the best people in the world who know how to measure methane. And we were after the best.”
Environmental Defense Fund