Don’t fall for the old “well, there are a lot of numbers out there” trick.
This US Department of Energy’s May 29 report still uses a laughably low maximum of 1.6% leakage rate to “prove” Liquefied Natural Gas (LNG) is better than coal.
Conservatively double that leaks, from a well-run life cycle; Stanford puts it as high as 7.1%
This is like when an article about climate change pops up, and within minutes 18 anonymous posts with links from GlenBeck.com or similar sources “prove” the icecaps are growing and honey bees are happy.
It is true that emissions estimates range and vary…ever-increasingly to the detriment of NG.
For perspective on the effect of all these percentages of leakage:
“Chesapeake Climate Action Network, an environmental group…finds that if the oil and gas system methane leak rate exceeds 1.9%, U.S. natural gas loses its greenhouse gas advantage over European coal” (when US gas is shipped to Europe):
While EDF (Environmental Defense Foundation, a pro-gas environmental group) says: “An overall system leak of 1.2% of production…equals the annual greenhouse gas emissions of 112 million cars and 140 coal-fired power plants:”
“Over a 20-year time frame, natural gas is as bad as or worse than coal and oil as a driver of climate change,” according to Howarth, R. W. (2014). A bridge to nowhere: Methane emissions and the greenhouse gas footprint of natural gas [Abstract]. Energy Science & Engineering. doi: 10.1002/ese3.35
Former Assistant Counsel to the Pennsylvania Public Utility Commission Mark Wieder recently published that: “A research team lead by Cornell University concluded that up to 40% of oil and gas wells drilled in Pennsylvania might end up (or already are) leaking methane. The argument goes that it is unwise to rely on natural gas as a replacement for dirtier coal. Methane is a more dangerous greenhouse gas than the CO2, and the reductions in CO2 emissions gained by decreasing the use of coal are diminished or eliminated when methane escapes from natural gas wells.” He cites the widely circulated report:
This report ends with the striking revelation: “One surprise, he added, was that the researchers could not find any inspection reports at all for 8,000 wells, even though the state is supposed to inspect them all once a year.”
Per our USEPA: “Pound for pound, the comparative impact of CH4 on climate change is over 20 times greater than CO2 over a 100-year period.”