Methane gas is the main component of natural gas, and there has been different scientific estimates on the amount of methane that leaks from wells, pipelines as well as other facilities during production and delivery.
Michael Shellenberger, President of the Breakthrough Institute tells the A.P. “This is great news for anybody concerned about the climate and strong proof that existing technologies can be deployed to reduce methane levels.”
In a mid-April report by the E.P.A. on greenhouse emissions, the organization now says as a result of the tighter pollution controls instituted by the industry resulted in an average annual decrease of 41.6 million metric tons of methane from 1990 through 2010, which works out to a 20 percent reduction from previous estimates.
The EPA says they made the changes based on expert reviews and new data from a number of sources, however the estimates are not based on independent field tests of actual emissions.
Despite the encouraging news, figures from the EPA still indicate natural gas operations are the main source of methane emissions in the U.S. despite the fact that all the sources of methane combined still account for only 9 percent of greenhouse gases.
The organization notes that they are still seeking further information on the subject, so the report may change in the future.