A Close Look at Fugitive Methane Emissions From Natural Gas _ WRI Insights

7/27/2019 A Close Look at Fugitive Methane Emissions From Natural Gas _ WRI Insights

1/3

Follow WRI:

Home Projects Topics Experts

A natural gas drilling rig. Photo credit: Justin Woolford, Flickr

A Close Look At Fugitive Methane Emissions From Natural

GasSubmitted by Michael Obeiter andJ ames Bradbury on April 2, 2013

Natural gas is booming in the United States. P roduction has

increased by 20 percent in the last five years, fueled largely by

technological advances in shale gas extraction. Other countries

including Chinaare now studying our experience with this

abundant new resource.

But the growing role of natural gas in the U.S. energy mix hasnt

come without controversy. Natural gas development poses a variety

of environmental risks. In addition to habitat disruption and impacts

on local water and air quality, one of the most significant concerns

is the climate impact resulting from the fugitive methane

emissions that escape into the atmosphere from various points

along the natural gas supply chain.

So what are fugitive methane emissions, and how big of a problem are they? How do emissions from natural gas compare to

those from coal? And are there ways to mitigate them? The answers to these questions will help us better understand how

natural gas development will affect climate change.

What A re Fugitive Methane Emissions, and How Do They Contribute t o Climate Change?

Methane, the primary component of natural gas, is a powerful greenhouse gas25 times stronger than carbon dioxide (CO2)

over a 100-year time horizon and 72 times stronger over a 20-year horizon. T hough methane represents only about 10-12

percent of all U.S. greenhouse gas emissions, it is a significant driver of short-term warming, and reducing methane emissions

can help slow the rise in global temperatures.

While proponents of natural gas often tout its green credentialscombustion of natural gas emits roughly one-halfthe CO2

of coal combustionthis is not the whole story. When it is extracted from the well, natural gas is composed of roughly 83

percent methane, after processing and through the point of delivery, it is more than 90 percent methane. Producing,

processing, and transporting of natural gas can release some of this methane into the atmosphere. Accidental methane leaksand routine ventingwhich together, make up fugitive methane emissionsreduce the comparative climate advantage of natural

gas for electricity generation. Plus, at current estimated leakage rates, fugitive emissions actually make compressed natural

gas a questionable choice for fuel-switching in cars and trucks.

What Is th e Extent o f th e Problem?

There is stillconsiderable uncertainty over the amount of fugitive methane emitted over the lifetime of a natural gas well.

However, some aspects generate little debatenamely, that emissions from natural gas production are substantial and occur

at every stage of the natural gas life cycle, from pre-production through production, processing, transmission, and distribution.

The U.S. Environmental Protection Agency (EPA)estimates thatmore than 6 million metric tons of fugitive methane

leaked from natural gas sys tems in 2011. Measured as CO2-equivalentover a 100 year time horizon, thats more

greenhouse gases than were emitted by all U.S. iron and steel, cement, and aluminum manufacturing facilities combined.

Many ongoing studies aim to provide more clarity on the extent of fugitive methane emissions from natural gas. Well get a

clearer picture when data from these studies is looked at in conjunction with industry data reported to the EPA Greenhouse

Gas Reporting Program. But with about 500,000 existing natural gas wells, thousands of miles of pipeline, and a growing

interest in natural gas development, well never have a truly complete picture of the amount of methane being emitted.

Is Natural Gas Better than Coal?

Considerable media attention has focused on the question of whether gas is better than coal from a climate perspective. On

the one hand, this question sets a low bar for environmental performancestudies have found that by just about any measure,

every other energy source is less damaging to the environment and public health than coal. On the other hand, this is an

important benchmark, since more than 30 percent of U.S. natural gas is used for electric power generation and more than 90

percent of all U.S. coal consumption is used for this purpose. The question has also received heightened attention as many

older, inefficient coal-fired power plants retire and natural gas-fired plants provide a growing share of total electric power

generation.

At the point of combustion, natural gas is roughly half as carbon-intensive as coal. However, this comparison fails to account

for upstream fugitive methane emissions. When used for electric power generation, natural gas is typically much more efficient

than coal, but natural gas is not a more energy efficient fuel option for all usesfor example, in the case of vehicles. Also, if

fugitive methane emissions exceed 3 percent of total gas production, natural gass climate advantage over coal disappears

over a 20-year time horizon.

Our Projects

Brazilian Business andEcosystem ServicesPartnership

Open Climate Network

Parceria Empresarialpelos ServiosEcossistmicos

MORE PROJ ECTS

Latest Posts

Rio de J aneiro Poised to Update

Its Greenhouse Gas Inventory

J uly 23, 2013

Fire Alerts Spike in Indonesia as

Risk of Haze Crisis Returns

J uly 22, 2013

Ensuring Economic Growth and

Environmental Sustainability in

Brazil

J uly 19, 2013

Why Climate Justice?

J uly 18, 2013

Browse by Topic

Rio+20

Climate Change

Forests

Water

More Topics

A World Resources Institute website publications programs donate WRI sites

ose Look at Fugitive Methane Emissions from Natural Gas | WRI Insights http:// insights.wri.org/news/2013/04/close-look-fugitive-methane-

7/24/2013


2/3

TAGS: climate change, natural gas, us policy

The critical question is: Given the current extent of U.S. natural gas productionand the fact that production is projected to

expand by more than 50 percent in the coming decadesare we doing everything we can to ensure that emissions are as low

as is technologically and economically feasible? The answer to that question today is clearly no.

How Can We Mitigate Natural Gass Impact?

Numerous cost-effective technologies can reduce fugitive methane emissions, which will curb global warming and save money

for energy companies and for consumers. While some companies are voluntarily implementing these technologies to varying

degrees, the industry is vast, including thousands of participants with diverse market interests. Much more can be done. In a

working paper to be published later this week, we discuss in greater detail the scale of the methane leakage issue, as well as

numerous policy and technology pathways for state and federal authorities to begin limiting these harmful emissions.

Ultimately, cleaning up fugitive methane should be an urgent priority to help slow the rate of climate change in the near-term.

Well also need policies to significantly reduce carbon dioxide emissionsfrom the combustion of natural gas as well as other

fossil fuels. To stabilize the climate at safe levels by mid-century, we need to address GHG emissions fromall sources.

Fugitive methane is one important, cost-effective opportunity that we can begin addressing today.

LEARN MORE: Stay tuned for our forthcoming working paper, Clearing the Air: Reducing Upstream Greenhouse Gas

Emissions from Natural Gas Systems, which will be released later this week.

5 Comments

Comments expressed on this page are opinions of the authors themselves, and not positions of the World R esources Institute or its

partners. WRI reserves the right to remove any com ments that it considers inappropriate or spam.

A renewab le/gas hybr id, o nly

Submitted by George Hillenbrand on J uly 2, 2013.

A renewable/gas hybrid, only burning gas as necessary, enables adoption of renewable sources, like solar, that can't

guarantee continuous output. Oil might satisfy the same role - but remember monster spills and recent wars for oil.

Coal doesn't turn on and off quickly, which makes it difficult to use coal in combination with renewable energy, i.e. at night with

solar, or on windless days. Coal plants are 50-100 year commitments, huge money is spent up front, and this money demands

unending trainloads of coal continue to be burned. When we postpone gas, we may well be postponing it for 50 years. I'd

rather see our money spent figuring out how to avoid gas leaks than spend the same money trying to mitigate coal emissions.

A proper comparison isn't just one fuel versus another, it's one complete infrastructure versus another. I love renewable

energy, so I like gas because gas makes renewable energy feasible sooner. As renewable energy becomes ubiquitous, just a

little gas should be needed for the relatively few days of the year when the sun simply isn't shining anywhere. That's the win.

reply

Please take this argument o ne

Submitted by Louise Stonington on April 15, 2013.

Please take this argument one step further, and also check your math.

Natural gas, when it burns, emits 117,000 tons of carbon dioxide (CO2) per billion BTU of energy output, oil emits 164,000 and

coal 208,000. So burning coal puts out 91 tons more CO2 per BTU than natural gas.

Natural gas is mostly methane, warming 72 times as much as CO2 over a 20 year period, and 25 times as much over a 100

year period. If we multiply that 91 ton difference by 72 by 3% we get 197,000, which if we add that to 117,000 gives us

314,000 Tons, way more warming potential than coal.

Therefor the statement, if fugitive methane emissions exceed 3% of total gas production, natural gass climate advantage over

coal disappears over a 20 year time horizon. Is somewhat inaccurate, it should read 2% emissions/leaks means that natural

gas just as bad as coal. If you use the lower warming multiple, as promoters of natural gas want to do, and over a 100 year

period, and then 4% methane leakage makes natural gas just as bad as coal.

So no one knows what the leakage rate is, but there are a few field studies, one in Colorado putting the rate at 4%, another

calculating 8%.

When natural gas is used in vehicles, extra energy used to compress it adds to its warming potential, making it clearly worse

for the climate than gasoline/oil.

Even if US regulations require developers to capture those leaks, there is no guarantee they can or will, and it is certain that

the 96% of the worlds reserves of natural gas in other countries will not.

The ramping up of use of natural gas is chilling the market and investment draw of green technology. We must stop saying that

natural gas is 'clean', or a 'bridge fuel' and oppose development for future use. We need energy investment to go into clean

energy, made in America, that we can export and out compete fossil fuels.

reply

We currently send $130

Submitted by Christian Miller on April 3, 2013.

We currently send $130 billion each year to OPEC in order to burn 1.5 billion barrels of oil in cars and trucks. We can stop

buying any oil from OPEC by converting just 23% of our vehicles to compressed natural gas (CNG). We need to be very

Recent Activity

4 Promising Themes Emerge in

U.S.-China Agreements at

Strategic and Economic

Dialogue | WRI Insights

18 people recommend this.

Be the first of your friends to

recommend this.

New Data Shows Indonesian

Forest Fires a Longstanding

Crisis | WRI InsightsBe the first of your friends torecommend this.

Facebook social plugin5

Like 22

96 8

15 1230


7/24/2013


3/3

careful with the fugitive methane emissions but let us stop sending money to the Middle East.

reply

Christian, What data do you

Submitted byJ im Pierobonon J une 17, 2013.

Christian,

What data do you have and/or what are your sources for the 23% conversion metric? P lease share here or email me at

your earliest convenience. Thanks!

reply

In making comparisons between

Submitted by EnviroAus on April 2, 2013.

In making comparisons between the LNG and coal industry it is important to include the fugitive release of methane through

the pre-draining of gas from coal seams prior to mining or its release during open cut mining operations.

reply

Post new comment

Your name: *

E-mail: *

The content of this field is kept private and will not be shown publicly.

Homepage:

Comment: *

No HTML tags allowed

Lines and paragraphs break automatically.

Web page addresses and e-mail addresses turn into links automatically.

CAPTCHA

This question is to verify that you are indeed an actual person, and not a spam-bot or other nuisance.

What code is in the image?: *

Enter the characters shown in the image.

By submitting this form, you accept the Mollom privacy policy.

What is WRI Insights

10 G Street NE Suite 800, Washington, DC 20002, USA / Phone +1 (202) 729-7600 / Fax +1 (202) 729-7610


7/24/2013

Documents

A Close Look at Fugitive Methane Emissions From Natural Gas _ WRI Insights