New research from scientists at NOAA and Carnegie-Mellon finds that natural gas production globally may be leaking enough methane to negate the climate benefits of gas over coal during the next two decades. Over a 20-year time period, methane is 86 times as potent a greenhouse gas as carbon dioxide.
Scientific American online reported June 26 (reposted from Climate Wire):
Leaky Methane Makes Natural Gas Bad for Global Warming
If leaks continue at present rates, natural gas may not help combat climate change
Natural gas fields globally may be leaking enough methane, a potent greenhouse gas, to make the fuel as polluting as coal for the climate over the next few decades, according to a pair of studies published last week.
An even worse finding for the United States in terms of greenhouse gases is that some of its oil and gas fields are emitting more methane than the industry does, on average, in the rest of the world, the research suggests.
"I would have thought that emissions in the U.S. should be relatively low compared to the global average," said Stefan Schwietzke, a researcher at the National Oceanic and Atmospheric Administration's Earth Systems Research Laboratory in Boulder, Colo., and lead author of the studies. "It is an industrialized country, probably using good technology, so why are emissions so high?" ...
The new research:
Stefan Schwietzke, et al., Natural Gas Fugitive Emissions Rates Constrained by Global Atmospheric Methane and Ethane, Environmental Science & Technology (American Chemical Society journal)
Stefan Schwietzke, et al., Global bottom-up fossil fuel fugitive methane and ethane emissions inventory for atmospheric modeling, ACS Sustainable Chemistry & Engineering
Prof. Robert Howarth at Cornell University, who has published research papers raising concerns about methane emissions from natural gas systems, argues that the proposed rule on carbon emissions from existing electric power plants, released by the Environmental Protection Agency for public comment on June 2, focuses on carbon dioxide but does not deal adequately with emissions of methane, a potent greenhouse gas. Howarth contends that the EPA plan "should be revised to reflect the importance of methane and the extent of methane emissions from using natural gas."
Scientific American/Climate Wire notes:
The Obama administration has supported the natural gas industry, in part for the fuel's climate benefits. Gas emits about half as much carbon dioxide as coal in the power plant, so the government has promoted gas as a transition fuel to a post-carbon future. ...
The fine print, however, is that natural gas may be as detrimental to the climate as coal in many ways. Its climate challenge lies not during electricity generation, but further upstream -- during extraction, processing and distribution of gas from the oil and gas wells to gas burners.
From wellheads, pipes, valves, compressors and various other equipment, gas wells leak raw methane, a greenhouse gas that is 86 times as potent as carbon dioxide over a 20-year time scale, according to the Intergovernmental Panel on Climate Change. ...
Using real-world global data, his models suggest that natural gas producers are leaking to the atmosphere, on average, between 2 and 4 percent of the natural gas they produce. ...
Various life-cycle analyses have found that in order for gas to be better than coal for the climate, the methane leakage rate has to be less than 3 percent. That overlaps the leakage found by Schwietzke.
Significantly ramping up production of natural gas from fracking is clearly an essential component of meeting the Obama administration’s 2020 goal for reducing U.S. greenhouse gas emissions “in the range of 17%” below the 2005 level. The administration is relying on currently low-cost natural gas to displace coal in electricity generation.
But how much does fuel-switching from coal to natural gas contribute to climate change mitigation, if at all? Can we really expect to substantially reduce total U.S. methane emissions while undergoing a major, rapid expansion in natural gas production? Will promoting the rapid expansion of low-cost natural gas undermine the introduction of renewable energy and energy efficiency measures, and thus undermine longer-term efforts to curb emissions and phase out fossil fuels?
Joe Romm, Climate Progress: Up To A Million Abandoned Wells In Pennsylvania Spew Heat-Trapping Methane
Another week, another bombshell study supporting the conclusion that natural gas has no net climate benefit in any timescale that matters to humanity.
This time it’s a Princeton thesis, which finds “Methane emissions from abandoned oil and gas [AOG] wells appear to be a signiﬁcant source of methane emissions to the atmosphere.”
Joe Romm at Climate Progress: Bridge Or Gangplank? Study Finds Methane Leakage From Gas Fields High Enough To Gut Climate Benefit