US oil firms attempting to address fugitive methane leaks

摘要

According to EPA data,fugitive methane emissions from US petroleum operations increased by 2.5% from 2005 to 2017 to 1.5MM mt,led by growth in fugitive emissions from upstream oil producers.Over this same period fugitive methane emissions from US natural gas producers decreased by 3.4% to 6.6MM mt.Environmental groups claim fugitive methane emissions from US oil and gas operations are underreported,noting that the EPA utilizes a”bottom-up”approach of estimating fugitive methane emissions at individual oil and gas sites,and then extrapolating these measurements to estimate the total fugitive methane emissions for the whole country.According to a paper from the Environmental Defense Fund,US fugitive methane emissions are at least 60% greater than what the EPA reports.To better track and report fugitive methane emissions from US oil and gas operations a”top-down”approach using sensors mounted on aircraft,satellites,and towers has been proposed to estimate methane levels in the US atmosphere,though this approach presents its own challenges.For one,methane levels in the atmosphere rise and fall with US natural gas demand,which tends to be higher in the winter months due to heating needs.Sandra Snyder,the Interstate Natural Gas Association of America's Senior Regulatory Attorney,said,”One thing that can be problematic about the 'top-down' approach is that you're assuming operations are steady-state and constant.That's just not the way that we necessarily operate.”