Is Natural Gas ‘Clean’?

The question is whether the natural gas “revolution,” which is a real thing — production is up about a third since 2005 — is also a good thing.

One reason natural gas is called “clean” is because it emits 50 percent less carbon dioxide than coal when you burn it. Thus it’s seen by some as a “bridge” fuel until zero-carbon-producing renewables can take over. But natural gas isn’t clean in the way that solar is clean. It’s clean-er than coal. It’s better than the worst; that’s all.

And the situation is actually too dire for a bridge fuel: experts say we must stop adding carbon into the air within the next 30 years [1] or face a climate “feedback loop” in which global warming continues regardless of subsequent activities, a point at which we would be able to make things worse but not better. If switching to natural gas long delays the dominance of renewables, it’s not doing us much good. That’s why action now is important.

Alternatively we could all buy land in the Arctic.

Then there’s this: Natural gas is made up mostly of methane [2], and methane, unburned, is around 70 times as potent a greenhouse gas as carbon dioxide. There isn’t nearly as much of it, and it’s shorter lived, but it’s not so short-lived that we can allow a great deal to escape into the atmosphere, which it does when anything in the production, transmission or distribution processes leaks [3]. It’s a scarily powerful greenhouse gas for over 20 years, and merely powerful (25 times stronger than carbon dioxide) over a span of 100 years. By which time much of the world’s coastline will be what we now call “inland.”

To see natural gas as even semi-clean, then, you have to burn all you take out of the ground [4]. Because at least one study found that if as little as 3 percent of the methane produced escapes, you might as well be burning coal, from a climate perspective [5]. All that talk of a bridge to a renewable future … forget it. That’s why Anthony R. Ingraffea, professor of civil and environmental engineering at Cornell University, refers to natural gas as a “gangplank.”

You’re wondering, “So how much of the methane we’re mining escapes into the atmosphere?” The answer is that no one knows, and finding out is complicated, because there are millions of oil and gas wells (many pump both) in the United States, and with “unconventional” technology (read: fracking) proving to be increasingly profitable, more wells are being drilled all the time. (One industry source estimates around 25,000 per year.)

For the past nine months I’ve been involved in shooting “Years of Living Dangerously,” a series about climate change to be released on Showtime next spring, and one of our topics is methane emissions. I’ve seen wells sending off huge plumes of gas in residential areas, compressors that are spewing methane so badly that some scientists won’t go near them without gas masks [6], and well fields where methane levels skyrocketed over “normal” background levels.

That’s all anecdotal, but researchers have done studies in Utah’s Uintah Basin, Colorado’s Weld County and the Los Angeles basin, and their estimates of emissions there are well over the critical 3 percent figure — sometimes almost four times as high.

There are also wells where the emission rate approaches zero, and beginning in 2015, per new Environmental Protection Agency regulations, that will be the required norm for new wells. But the regulations will not affect the millions of old wells. Nor do they affect transmission and distribution pipelines, which are most likely a big source of emissions. There are more than two million miles of these, some of them 100 years old and made of cast-iron. There’s every reason to be worried about leaks from them, too, as studies in Boston and Washington, D.C., have indicated.

As long as the industry can claim that the emission rate is around 1 percent (a suspect estimate supported by the E.P.A.), the “clean bridge to a renewable future” scenario seems at least a little credible. But scientists from the National Oceanic and Atmospheric Administration (NOAA) are measuring high leak rates in a variety of different locations.

Even hundreds of big leaks don’t necessarily mean the overall leak rate is terrible. But the existence of what are sometimes called super-emitters means that meaningful measurements may be hard to come by. It’s not uncommon to find a small percentage of polluters giving off the majority of pollution; that was the case with cars before the requirement of the catalytic converter.

This leads to the report, released last week by a University of Texas team, of a study initiated by the Environmental Defense Fund (E.D.F.) with the cooperation of nine volunteers from the energy industry. E.D.F. is conducting a continuing series of studies, but this first one — which looked at 489 wells — found an acceptable leak rate of less than 1 percent. This confirms that existing technology works when used on new wells. If you took this as representative, you could sleep better.

Stay awake. First of all, the study found higher-than-expected leaks at valves on some of the same sites. More important, there are huge parts of the system that the study didn’t cover (nor did it pretend to), elements that E.D.F. hopes to get to by the end of next year. This study did what it intended to do, but it was a small study of a small part of a big system. A small study of a different small part of the system could yield entirely different results.

Which didn’t stop these kinds of headlines: “EDF Burned by Its Own Fracking Study, Sez Gas Experts” (E.D.F. would disagree) and “U.S. Overstates Leaks by Gas-Drillers, Says Study” (well, in new, green-completed wells, perhaps). Nor did it stop accusations that the E.D.F. had been bought out by the industry — which partially financed the study — or speculation that the leak rates, once finally measured accurately and thoroughly, will be found to be on the wrong side of 3 percent.

A couple of weeks ago, in Damascus, Ark., an unlikely source said to me, “We’re wasting time arguing about the percentage of methane leaks; we just have to do what’s right and necessary, and that’s to drive those emission rates down.” The source was Mark Boling, president of the development division of Southwestern Energy, a huge player in natural gas drilling.

Boling’s company has put its money where his mouth is — all of their wells are clean — but they are a small part of the puzzle. It’s cost-effective to make sure new wells meet the E.P.A. standards; it may even be cost-effective to retrofit existing wells to meet those same standards, although the E.P.A. isn’t requiring that and it’s unlikely that producers will do it voluntarily. But to make sure that processing plants, compressor stations and pipelines are also zero emitters (not required by the E.P.A.) is a project that will cost tens or hundreds of billions of dollars. Swapping coal plants for natural gas plants is estimated to cost hundreds of billions dollars — or more. All of these costs would be borne by rate payers (that is, you) or the federal government (that is, you).

If methane emissions from wellhead to electrical generating plants or your burner tip were at 1 percent — hard to believe, but let’s say it’s the case — that makes methane better than coal. But from a climate change perspective, “better than coal” is not good enough. And slightly better than coal is absurd.

We’re running out of time to measure emissions, and we’ll never arrive at an absolute number anyway. Embarking on a huge push to real renewables, and accepting the costs — which may actually be less than making natural gas “clean” — is the only responsible path to take. The real bridge to renewables is to begin to dismantle the existing infrastructure, starting with coal and nuclear — while using it as necessary to fill in the inevitable gaps as we build a new infrastructure of power from solar, wind and more.

If that’s impossible, we blew it. And if you plan to be on earth 50 years from now, I’ve got a nice piece of land in Murmansk I’d like to show you.

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1. This is an estimate, of course. No one knows.
2. It also contains a host of what are called VOCs (volatile organic compounds), many of which are pollutants and/or health hazards in their own right. The Environmental Protection Agency (EPA) doesn’t regulate methane directly, but controlling for VOCs could effectively control methane. But EPA doesn’t regulate VOCs very well either. Then of course there’s the whole fracking process ….
3. This isn’t about fracking, it’s about any and every method of mining, processing, and moving natural gas. I’ll save the question of fracking for another time, but . from the methane-spillage perspective, we don’t care whether a well is fracked or “conventional,” and we don’t care where the gas in the pipeline came from.
4. It would help, too — seriously — to start capturing and using the methane emitted from the thousands of cows you find at mega-dairies.
5. Natural gas is still cleaner than coal from most other perspectives.
6. One particular compressor has been in this state for at least a year, despite repeated calls to both the operator and the EPA.