Natural gas wells, seen as a “greener” alternative to coal and oil and more immediately accessible than solar or wind power, may actually be leaking more harmful gases than expected. The reports of this leakage are casting more doubts on the true effectiveness and environmental benefit of natural gas production.
Gabrielle Petron, a scientist with the US National Oceanic and Atmospheric Administration (NOAA) and the University of Colorado, reported 4% of methane produced in a field in Colorado was leaking into the atmosphere, and that some fields in Utah may be leaking up to 9% of the methane produced. Methane is the primary ingredient of natural gas; its leakage contributes to the overall greenhouse effect that results in global warming.
Studies by the US Environmental Protection Agency (EPA) pointed to an average methane leakage rate of about 2.4%. Another study, by the Environmental Defense Fund, stated that as long as leakage stayed below 3.2%, then natural gas affected global climate less than old, coal-fired power plants. Rates of 4 to 9%, therefore, create serious questions about the decision to convert power plants to natural gas.
It is unknown if Petron’s reports are an anomaly or represent the production of all gas wells in the United States (not to mention worldwide). NOAA and scientists from the University of Texas are undertaking a more comprehensive review of natural gas wells. At the same time, studies that examine the impacts of “fracking” (the use of water and other fluids to dislodge deep natural gas deposits) are also pointing to parts of the natural gas mining process that could be improved to reduce leakage.
Pétron, G., et al. (2012). Hydrocarbon emissions characterization in the Colorado Front Range: A pilot study Journal of Geophysical Research, 117 (D4) DOI: 10.1029/2011JD016360
Photo: Cedar Hill, Texas