Analysis of Natural Gas Production in the Marcellus Shale: Understanding the Distribution of Fugitive Methane Emissions and Characterizing the Traits of 'Super-emitters'

Abstract

As natural gas becomes an increasingly prominent and influential player in thedomestic energy market, concerns about the climate impact of the transition has risen tothe forefront of research and discussion. The astounding growth in the sector is driven byadvances in drilling technology, accessing previously uneconomical reserves and retrievinghigh volumes of natural gas. While natural gas combustion produces only half as muchcarbon dioxide as coal, the primary component of natural gas is methane, a much strongergreenhouse gas compared to carbon dioxide. Multiple studies have found significantamounts of fugitive methane emissions from natural gas infrastructure, which can offset thebenefits achieved from a cleaner combustion.This thesis analyzes one of the largest datasets of fugitive methane emissions,collected from a field campaign in the Pennsylvania Marcellus shale, one of the mostproductive regions of natural gas. Similar to previous research, this study has found anextremely skewed distribution of emissions, such that a small subset of ‘super-emitter’ wellscontribute to an overwhelming 90% of emissions. Statistical analyses revealed no strongcorrelations between large emitters and production volumes, age of the well, or anyindividual company. Yet, a mitigation strategy can still be formulated, emphasizing that olderwells and higher producer wells are simply more likely to be super-emitters. A case study onthe financial merits of using leak detection and repair on super-emitters are immediate andpositive.