Natural gas is being touted as a “game changer” and a “bridge to a low carbon economy.” It is an abundant, made-in-America energy source.  It is about half as carbon intensive as coal when burned. The figure below suggests that a natural gas fueled transition to a less carbon intensive economy has already begun. Domestic, energy-related carbon dioxide emissions have declined 12 percent since the peak in 2007. An important driver of this trend is the substitution of natural gas for coal in electricity generation. Of course, this picture gets much more complicated when you look upstream and broaden your perspective to consider not just carbon dioxide -the most prevalent anthropogenic greenhouse gas- but also “fugitive” methane emissions. Methane, the primary constituent of natural gas, can escape during extraction, processing, and distribution. These emissions have the potential to eliminate the carbon advantage of gas over coal and oil. There […]