Life cycle greenhouse gas emissions from Barnett Shale gas used to generate electricity

•Central estimate for 2009 Barnett Shale life cycle GHG emissions is 440 g CO2e/kWh.•Life cycle GHG emissions vary by well lifetime production, 420–510 g CO2e/kWh.•The vast majority of GHG emissions are not affected by the type or origin of gas.•Methane leakage comes mostly from potentially controllable sources.•Gas composition variability can affect GHG estimation at fine spatial resolution.

This paper presents research findings on life cycle greenhouse gas (GHG) emissions associated with natural gas production in the Barnett Shale play in Texas. The data sources and approach used in this study differ significantly from previous efforts. The authors used inventories from the year 2009 tracking emissions of regulated air pollutants by the natural gas industry in the Barnett Shale play. These inventories were collected and screened by the Texas Commission on Environmental Quality (TCEQ). These data cover the characteristics and volatile organic compound (VOC) emissions of more than 16,000 individual sources in shale gas production and processing. Translating estimated emissions of VOCs into estimates of methane and carbon dioxide emissions was accomplished through the novel compilation of spatially heterogeneous gas composition analyses. Life cycle greenhouse gas emissions associated with electricity generated from Barnett Shale gas extracted in 2009 were found to be very similar to conventional natural gas and less than half those of coal-fired electricity generation.