Methane leaks might mean natural gas is not more climate-friendly than coal, but no one really knows

A study by the World Resources Institute found that we have no idea how much methane, a greenhouse gas much more potent than carbon dioxide, is leaking from the 500,000 natural-gas wells and hundreds of thousands of miles of pipeline in the U.S. "Technologies to plug those leaks are readily available, but new regulations may be necessary to make sure they’re widely adopted," Brad Plumer reports for The Washington Post. And that may not be all.

The Environmental Protection Agency estimated that only about 2.4 percent of methane leaks into the air, but that "is essentially an educated guess, based on a number of assumptions rather than direct measurements," Plumer reports. The study says the "next step is to try to reduce the leakage rate to around 1 percent — which would ensure that natural gas is cleaner than coal when used for electricity, and cleaner than diesel fuel when used for transportation."

Plumer writes that reducing the leakage to 1 percent could be accomplished using plunger lift systems that "allow drillers to remove excess liquid from their wells without letting a whole bunch of methane escape into the air" and low-bleed pneumatic devices, which can "cut down on leaks throughout the system. As could better monitoring and repair systems." (Read more) "That's all well and good, but new regulations won't mean anything unless they are enforced," said Al Cross, director of the Institute for Rural Journalism and Community Issues and former oil-and-gas reporter. "Such regulation is up to the states, which have a spotty enforcement record, and whose main interest is prevention of visible environmental harm, not limiting greenhouse gases."