In a sane world, we would be very concerned about measuring, reporting and closely regulating methane releases during its extraction and processing, especially if we claim that it is clean energy. This is nothing I, or other people haven’t said before, but here’s more research summarized in the very respectable Nature Journal indicating that measurable leak rates of methane can vary widely.
Preliminary results from a field study in the Uinta Basin of Utah suggesting even higher rates of methane leakage — an eye-popping 9% of the total production. That figure is nearly double the cumulative loss rates estimated from industry data — which are already higher in Utah than in Colorado
via Methane leaks erode green credentials of natural gas : Nature News & Comment.
10% is a large number. I’ve posted this picture from Wigley (2011) previously. At any leakage rate other than zero, which no one claims, the benefits of switching from coal to methane are very modest.