Shale Gas Can Build New Bridges if Latest Methane Studies are Right
University of Texas Study Gives Positive Review
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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