Oops. Methane Leakage from Fracked Wells “Alarmingly high..”
August 7, 2013
Full disclosure. Like a lot of other houses, mine is heated in the winter with natural gas – methane. I’ve taken a lot of steps to make the house much more energy efficient than it was when I moved in- including better insulation, new windows, efficient furnace – and I know it uses a lot less energy than it used to. Still, I’m looking for other alternatives.
For the moment, we are stuck with natural gas as a widely used fuel. That’s something that probably needs to change sooner than we thought – certainly sooner than the rosy “100 years of natural gas” scenarios contemplate.
The leakage of natural gas from well heads, pipelines, and fracked fields is a major challenge, and seemingly turns the “natural gas is a bridge fuel” argument, one that I’ve subscribed to in the past, on its head.
Almost a tenth of the methane produced from oil and gas operations in a Utah site escapes into the atmosphere, according to a federally backed study published Monday.
An analysis of the report from the Environmental Defense Fund called the emission rate “alarmingly high.”
The study, which included researchers from the National Oceanic and Atmospheric Administration among others, was published Monday in the journal Geophysical Research Letters.
It found that 9 percent of methane produced from drilling sites in a portion of Utah’s Uintah Basin escaped, said Colm Sweeney, one of the study’s main authors and a scientist at the National Oceanic and Atmospheric Administration’s Earth Systems Research Laboratory in Boulder, Colo.
Brian Straessle, a spokesman for the American Petroleum Institute, said the industry trade association hasn’t reviewed the new report, but cited other studies that found the portion of methane that escapes from wells is less than 2 percent.
Sweeney said the higher level found in the Uintah Basin study could cancel out environmental advantages of burning natural gas produced there.
He noted that natural gas is efficient because compared with other fossil fuels its combustion releases less of the greenhouse gas carbon dioxide, which is linked to climate change.
“But in order to properly account for this global warming benefit, you have to account for the leakage from the well hole to the point of use — and so that’s the critical problem that we’re trying to understand better,” Sweeney said.
High emissions of methane are troubling, Sweeney said.
“Methane immediately out of the ground will have a warming potential that is 100 times greater than carbon dioxide,” he said. “So you need a lot less methane to get a much higher global warming effect.”
When US government scientists began sampling the air from a tower north of Denver, Colorado, they expected urban smog — but not strong whiffs of what looked like natural gas. They eventually linked the mysterious pollution to a nearby natural-gas field, and their investigation has now produced the first hard evidence that the cleanest-burning fossil fuel might not be much better than coal when it comes to climate change.
Led by researchers at the National Oceanic and Atmospheric Administration (NOAA) and the University of Colorado, Boulder, the study estimates that natural-gas producers in an area known as the Denver-Julesburg Basin are losing about 4% of their gas to the atmosphere — not including additional losses in the pipeline and distribution system. This is more than double the official inventory, but roughly in line with estimates made in 2011 that have been challenged by industry. And because methane is some 25 times more efficient than carbon dioxide at trapping heat in the atmosphere, releases of that magnitude could effectively offset the environmental edge that natural gas is said to enjoy over other fossil fuels.
“If we want natural gas to be the cleanest fossil fuel source, methane emissions have to be reduced,” says Gabrielle Pétron, an atmospheric scientist at NOAA and at the University of Colorado in Boulder, and first author on the study, currently in press at the Journal of Geophysical Research. Emissions will vary depending on the site, but Pétron sees no reason to think that this particular basin is unique. “I think we seriously need to look at natural-gas operations on the national scale.”
The results come as a natural-gas boom hits the United States, driven by a technology known as hydraulic fracturing, or ‘fracking’, that can crack open hard shale formations and release the natural gas trapped inside. Environmentalists are
worried about effects such as water pollution, but the US government is enthusiastic about fracking. In his State of the Union address last week, US President Barack Obama touted natural gas as the key to boosting domestic energy production.
One of the boldest claims made by the shale gas industry goes like this: oil and gas companies have drilled and fractured a million oil and gas wells with nary a problem.
In other words fracture fluid or methane leaks are “a rare phenomenon.”
But industry data disproves this dubious claim says Cornell University engineer Anthony Ingraffea, the main source for this series, who has studied the non-linear science of rock fractures for three decades.
Moreover industry studies clearly show that five to seven per cent of all new oil and gas wells leak. As wells age, the percentage of leakers can increase to a startling 30 or 50 per cent. But the worst leakers remain “deviated” or horizontal wells commonly used for hydraulic fracturing.
In fact leaking wellbores has been a persistent and chronic problem for decades. Even a 2003 article in Oil Field Review, a publication of Schlumberger, reported that, “Since the earliest gas wells, uncontrolled migration of hydrocarbons to the surface has challenged the oil and gas industry.”
Going up
Methane, by its very lightness, wants to go up. Where ever drillers have not properly sealed and cemented wellbores in deep shale rock, the gas will escape and move through rock fractures (existing or industry-made ones) into groundwater, stream beds, water wells and even the basements of houses.
Aging can affect leakage too. Old and decaying cement jobs largely explain why offshore oil wells in the Gulf of Mexico report leakage rates as high as 60 per cent after 16 years of service. Abandoned wells also can become major pollution portals.
Climate Denial Crock of the Week 
August 20, 2013 at 1:33 pm
[…] issue, but it definitely takes away some of the charm of natural gas. The more alarmist view of methane losses from fracking can be found in many places, if you want to arrive at a balanced view. The fossil fuel industry […]