This article reports very "preliminary" data on methane leakage rates from natural gas fields in Colorado and Utah which document that between 4 and 9 % of the methane produced was leaking into the atmosphere. The Utah data with the 9 % emissions was apparently unpublished, and simply was reported at a recent American Geophysical union meeting, so there may not even be a published abstract to cite.
If these rates hold, true, they eliminate any climate benefit from using natural gas as a replacement for coal. Of course, without a significant price for carbon, basic economics means that most natural gas will be used "in addition" to, not as a replacement for, coal, and any purported climate benefit is meaningless.
These data contradict recent reports from EPA and US-EIA that American greenhouse gas emissions have declined, largely due to gas substituting for coal in electricity generation. The electric generation data do not account for these fugitive emissions from leaking gas wells and pipelines.
The take-home message is that we need to become much more focused on enforcement of air pollution from gas wells, or else ban shale gas altogether, as the emissions from shale gas well completions swamp most other losses, and this could mean "game-over" for the climate.
JBK
>>> "Ann Payne" <notification+zlrdzo1f@facebookmail.com> 1/3/2013 12:23 PM >>>
