Shale Gas Can Build New Bridges if Latest Methane Studies are Right

When it comes to fueling power plants, natural gas has become the path of “least resistance.” But one impediment to becoming the “fuel of choice” has been concerns over excessive methane releases, which is the most potent greenhouse gas of them all. A new study, though, is easing some of those worries.

In a world, generally, focused on producing electricity in the cleanest possible fashion and with an eye toward minimizing heat-trapping emissions, natural gas has emerged as the most optimal path forward. The ability to access the once-hard-to-find shale gas deposits is why. And hydraulic fracturing is the technique that has unleashed this now-abundant and cheap energy source. The reality is that domestically produced carbon dioxide emissions are down in four of the last last six years, mainly because of the transition from coal to natural gas and partly because of persistent economic malaise. 

However, an array of doubters are dousing the possibilities. Their concerns are valid -- everything from fouling surface waters to inordinate methane releases. Methane, according to scientists, is 72-times more powerful than carbon dioxide when it comes to trapping heat, although the methane dissipates after 20 years whereas the carbon dioxide stays active for a 100 years. 

Estimates have varied that the current wells eject anywhere from 1-to-8 percent of methane. A study released by Environmental Defense Fund and the Princeton University have concluded that if those releases exceed 3.2 percent then any benefits of switching from coal to natural gas are lost. This latest study from the University of Texas says that the level of escaping methane is at 0.42 percent. 

“We know that immediate methane reductions are critical to slow climate change," says Fred Krupp, president of the EDF. “But we don't yet have a handle on how much is being emitted. We need better data, and that's what this series of studies will deliver.” ??

This study follows one by the U.S. Environmental Protection Agency that says that the amount of methane that is leaked into atmosphere during the production and piping of shale gas has fallen by 20 percent from 1990 to 2010 because of tougher regulations and better equipment. Those escapes are now at 1.5 percent, EPA says. 

More Work

The University of Texas study, published in the Proceedings of the National Academy of Sciences, was funded by several interests that include 9 oil and gas companies, as well as the EDF. To be clear, the research looked at 2 percent of the existing wells, and just about all of them were newer wells that applied the latest and greatest technologies. ??

It did not examine the pipeline network used to transport the natural gas, which is another source of leaking methane. That will come, as such releases account for about half of all methane releases tied to the shale gas phenomenon. ??

Critics were quick pounce on the findings, noting that the study was bankrolled primarily by fossil fuel developers. At the same time, they emphasized that the review only examined 489 sites while it didn’t even evaluate the pipeline system. 

Furthermore, several environmental groups are pointing to an examination done last year by the National Oceanic and Atmospheric Administration and the University of Colorado. That analysis is showing that air samples in Colorado and Utah that are near fracking wells had a 4 percent methane leakage rate and that it could be much as 9 percent.??

Meantime, a Cornell University study conducted two years ago concluded that total greenhouse gases over 20 years as a result of exploring for shale are at least 20 percent greater when compared to those of coal. That’s because natural gas is composed mostly of methane.

EDF, however, says that the finding are subject to peer-review. But the organization, is not suggesting that its work is done. More such studies are expected. According to EDF’s Chief Scientist Steve Hamburg, the low emissions are the result of EPA regulations that are working -- ones that require producers to capture and either burn off the escaping methane, or to harness it and then re-sell it into the market for -- among other reasons -- home-heating purposes. ??

Technically speaking, EPA has labeled that process “green completions,” which is a phase-in of the so-called New Source Performance Standards. Some producers have called those rules onerous but EDF says that the regulations are the reason for the successful methane tests. In other words, without oversight, the methane results would exceed the 3.2 percent threshold and the public outcry would eventually demand a cessation of shale gas drilling until industry got control of the situation. Those regulations will be fully implemented in 2015. 

EDF says that the higher-than estimated leaks from “valve controllers” that are part of the pipeline network is where focus must now turn: “It shows that when producers use practices to capture or control emissions, such as green completions, methane can be dramatically reduced. The study also demonstrated, however, that certain methane emissions are larger than previously thought, indicating that there are many further opportunities to reduce emissions,” says Mark Brownstein, climate director for the group. 

One can expect that the drilling technologies will only get better. But limiting methane releases from production is one issue. Minimizing those emissions from pipeline transport is another. There’s still work to do, if natural gas is to remain a “bridge fuel.”

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