By JOHN SCHWARTZ
December 22, 2014
MEAD, Colo. — Natural gas is the Rorschach test of energy policy. Depending on one’s point of view, it can be either an essential tool for meeting the challenge of climate change or another dirty fossil fuel that will speed the planet down the path to calamitous warming.
President Obama is in the first camp. He sang the praises of natural gas in his State of the Union address in January, saying, “If extracted safely, it’s the bridge fuel that can power our economy with less of the carbon pollution that causes climate change.” But many environmental activists have denounced shale drilling because of the potential health risks that were cited by Gov. Andrew Cuomo of New York last week when he announced a ban on hydraulic fracturing in the state.
They also say that the growing use of plentiful natural gas is accelerating climate change and sapping the urgency to promote energy efficiency and developing renewable energy sources like wind and solar power. “It’s time to stop searching for a bridge and simply take the leap,” Bill McKibben, an environmental campaigner, said earlier this year.
Because burning natural gas produces about half the planet-heating carbon dioxide than coal does for the same energy output, many energy experts suggest that natural gas has an important role to play in reducing carbon emissions. But in the debate over natural gas, nearly every fact is contested, including the amount of methane, a potent greenhouse gas, that escapes into the atmosphere while the gas is being drilled and transported. There is little doubt, however, that the abundant natural gas unearthed by hydraulic fracturing (also known as fracking) and other drilling technologies have transformed the energy economy. Natural gas now produces 27 percent of the electricity generated in the United States, and the percentage is rising. The plentiful oil and gas from the drilling boom has reduced America’s dependence on foreign oil to levels not seen in decades, and has contributed to falling oil prices.
Anadarko, one of the nation’s biggest gas producers, boasts a site so clean that on a chilly day in November a rabbit opted to sit below one of its warm tanks. The company uses infrared cameras to detect leaks and then plug them quickly.
But recent studies suggest the effects of relying on natural gas and expanding its use will provide no lasting benefit to the environment compared with burning coal unless policies are enacted to hasten the adoption of renewable technologies — to make the bridge a short one.
Since 2005, carbon emissions from electricity generation dropped to 2.05 billion metric tons a year in 2013 from 2.5 billion. (They rose slightly this year because of the unusually cold months in early 2014.) But continuing to expand the use of natural gas instead of lower-carbon alternatives could wipe out any gains, said Haewon C. McJeon, a researcher with Pacific Northwest National Laboratory who participated in a recent study on natural gas.
“In the absence of a climate-change-mitigation policy, having abundant, low-cost natural gas alone is not going to significantly reduce greenhouse gas emissions,” he said.
The best role for natural gas is as a complement to renewable energy sources, said Hal Harvey, who runs a policy research group called Energy Innovation in San Francisco. He noted that power plants that run on natural gas can ramp up more easily than, say, coal or nuclear plants, and can fill the energy gaps for solar panels and wind turbines when the sun is not shining or the wind dies.
Gas-fired plants can also be built relatively quickly and cheaply — factors that led to a jump in gas-plant construction that actually preceded the natural gas boom.
But the advantages of natural gas are offset, in part, by persistent problems and questions surrounding leaks of its main component, methane. Because of methane’s ability to trap infrared radiation more effectively than CO2, its effect on climate change is 84 times greater on a 20-year basis. However, its life in the atmosphere before being eliminated by chemical reactions is measured in years, while CO2 persists for centuries.
Methane comes from many sources — the most recent Environmental Protection Agency inventory of greenhouse gas emissions estimated that a quarter of the total comes from burps and flatulence from cows and other livestock (the microbes in their digestive systems produce methane as a byproduct of breaking down their feed).
The methane that is created or that escapes from using natural gas as an energy source represents 23 percent. Other sources include coal beds and landfills. The Environmental Protection Agency estimate puts the amount of methane released from drilling and transporting natural gas at eight million metric tons a year, but recent reports suggest the figure could be far larger.
Anthony R. Ingraffea, a researcher at Cornell University who has been sharply critical of fracking, said that the gas industry had been lax in what it calls “wellbore integrity,” which refers to the steel and cement that drillers use to seal off wells from the surrounding rock, soil and groundwater. The seal tends to deteriorate over time, he said, and abandoned wells have been found to leak methane, as well. “Out of the four or five million wells drilled on earth, nobody knows how many of them are leaking into the atmosphere, or how much they are leaking,” he said.
The industry points to progress that has already been made in reducing methane emissions — a 73 percent decrease from hydraulically fractured wells since 2011, according to the E.P.A.
“It’s difficult to look at the available data and say there is a huge problem here,” said Steve Everley, a spokesman for Energy in Depth, an industry group. “Not only is production increasing, but emissions are going down.”
The agency’s figure on lower emissions from wells, however, does not account for the leaks that commonly occur farther downstream in the production process, where equipment like pneumatic devices and compressors have been identified as emissions sources. Research sponsored by the Environmental Defense Fund suggests that gas leaks can be cut by 40 percent at a relatively low cost: a penny for every thousand cubic feet of natural gas produced.
“The good news is we know we can get significant reductions for marginal cost,” said Mark Brownstein, associate vice president of the organization’s United States climate and energy program. Producers and regulators must do a better job of reducing risk, he said.
Fixing the problem of leaking methane can be achieved more easily than many other environmental challenges, said Mr. Harvey of Energy Innovation. Compared with “thermodynamic problems” like making automobiles more efficient and “chemical problems” like reducing smokestack pollutants, methane is largely a “plumbing problem,” Mr. Brownstein said, and “plumbing is dead simple.”
One of the nation’s biggest gas producers, Anadarko, said that gas leaks can be minimized without much effort. The company consulted with Colorado regulators on trailblazing state rules that call for drillers to use infrared cameras to detect leaks and then plug them quickly.
Here in Mead, 45 miles north of Denver, a production facility prepares the oil and gas from six wells for pipelines that will take the fuel to processing facilities. The big machines separate oil and recovered fluid from natural gas, and put about six million cubic feet of natural gas into the pipeline every day.
Wrench-wielding Anadarko inspectors search for leaks — “fugitive gas” — as often as monthly at major facilities, and tighten flanges that may have shaken loose. The equipment, too, is designed to minimize leaks. The valves on these pneumatic devices are run with compressed air; the more standard industry practice is to use the pressure of the extracted natural gas to power them, which means gas can escape. Instead, what is vented here is simply air.
Not every company takes such pains, and industry experts say there is a big difference between the best actors and some of the smaller players who generate more than their share of environmental damage.
Korby Bracken, Anadarko’s director of health, safety and environmental issues in the Rockies, invited a visitor to look inside the steel smokestack column through a small sight glass. A pilot light burned inside, and after all the effort to capture, contain and sell gas, having it consumed in a six-inch column of flame clearly irked him. “We’d rather put it in the pipeline,” he said.
Anadarko officials say their goal is to use the technologies employed at this site — which was so clean that a rabbit sat below one of its warm tanks, grooming its ears, on a chilly November day — wherever possible. Some sites are too remote for an electrical hookup to power air compressors, but the infrared cameras are being used throughout the company’s facilities.
The Obama administration has tried to straddle the promise and risks of the natural gas boom by hailing the benefits of increased production while targeting carbon and methane emissions. The Environmental Protection Agency proposed rules in June, known as the Clean Power Plan, to reduce carbon produced by electricity plants. That would call for more plants to run on natural gas rather than coal which currently produces 74 percent of all carbon dioxide emissions in the United States.
The plan also would require greater use of renewable energy sources and nuclear power in order to meet the president’s target, announced last month with China, of reducing greenhouse gas emissions by as much as 28 percent by 2025.
In March, the administration announced the plan aimed at reducing methane leaks. The E.P.A., under this “Strategy to Reduce Methane Emissions,” is expected to publish its proposed rules next month.
Ultimately, fighting over the relative merits of natural gas compared to other fossil fuels misses the broader energy challenge for the nation and the world, said Steven Cohen, the executive director of the Earth Institute at Columbia University.
“Everybody’s looking for a big fix — a magic bullet,” Mr. Cohen said. “I don’t think any of the existing technologies will do what we need to do to get to the renewable energy economy.” The challenge, he added, is to spur the same kind of technology revolution that transformed bulky computers into pocket-size devices.
“You need some kind of technology that doesn’t exist now,” he said.
Natural Gas: Abundance of Supply and Debate - New York Times
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