ExxonMobil Aims to Prove Gas is Cleaner Than Coal

New ExxonMobil methane leakage study aims at coalExxonMobil has had a horrible four-week run in the aftermath of its Pegasus pipeline break in Arkansas, but a just-published greenhouse gas emissions study by the company’s research arm could provide a bit of a bright spot amidst the gloom. The new ExxonMobil study looks at the total lifecycle of natural gas from drilling to power generation, and concludes that its carbon footprint can be significantly lower than coal.

Lifecycle emissions are a huge issue for ExxonMobil and the natural gas industry. Natural gas emits far less greenhouse gases than coal when burned at power plants, but evidence has been emerging that this benefit could be completely wiped out by methane leakage at gas drilling fields and other earlier points in the lifecycle. So, before the cheering starts around the water coolers over at ExxonMobil or anywhere else, let’s take a closer look at the new study.

The ExxonMobil emissions study

Our friends over at The Hill have a pretty good rundown of the study and its implications for ExxonMobil, which as an oil-and-gas company is in direct competition with coal in the utility power generation market.

Basically, the study (just published in the American Chemical Society’s Environmental Science and Technology journal) found that the carbon footprint of the overall lifecycle of natural gas was 53 percent lower than coal. That finding is based on CO2eq, which is a standard unit of comparison among different greenhouse gases, including methane.

The main thing to note is that the study is specific to natural gas from the Marcellus shale region in the Northeastern U.S., which has become notorious due to its reliance on the natural gas drilling method known as fracking. That’s significant because at the drilling stage of the natural gas lifecycle, rates of methane leakage can vary significantly from one gas field to another.

For example, while the ExxonMobil study indicates that methane leakage from gas fields in the Marcellus is relatively insignificant compared to overall lifecycle emissions from Marcellus gas, earlier this year the National Oceanic and Atmospheric Administration confirmed previous findings for a field located in Colorado that suggest the potential for far greater rates of methane leakage elsewhere.

Since the study compares Marcellus gas to “U.S. coal,” that makes it pretty difficult to draw general conclusions about its usefulness for power plant owners who are seeking ways to reduce greenhouse gas emissions. The only real takeaway is that, so long as both coal and gas remain key players in the U.S. energy landscape, choosing one over the other in terms of reducing greenhouse gas emissions is an extremely complex proposition that calls for energy managers to delve deeply into comparative lifecycle emissions on a field-by-field, mine-by-mine basis rather than simply looking at power plant emissions.

Add to that the other risks involved in fracking, including water contamination and earthquakes related to wastewater disposal, and you’ve got an even cloudier idea about which fossil fuel is more sustainable than the other.

The big showdown between coal and gas

That brings us to an interesting twist in the politics of climate science and renewable energy. Before it became ExxonMobil, Exxon was notorious for its campaign against climate science through the funding and promotion of the climate change “skeptic” position, particularly by lobbying groups such as the Heartland Institute.

In recent years, Exxon has taken a more relaxed approach to promoting climate change denial, though possibly that is due less to a change of heart and more to the realization that climate change can work in its favor by enabling it to grow its natural gas operations at the expense of coal.

In that regard, it’s also worth noting that that another notorious climate change denial voice, that of the Koch brothers, was one of the funders behind last year’s Berkeley Earth Surface Temperature study (BEST). The study basically re-confirmed previous climate science findings, but that’s not to say that the Koch brothers were dismayed at seeing their favored position blown to bits, since they also have a significant stake in the natural gas market.

[Image: Refinery flare by Kristian Dela Cour]

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Tina writes frequently for Triple Pundit and other websites, with a focus on military, government and corporate sustainability, clean tech research and emerging energy technologies. She is a former Deputy Director of Public Affairs of the New York City Department of Environmental Protection, and author of books and articles on recycling and other conservation themes. She is currently Deputy Director of Public Information for the County of Union, New Jersey. Views expressed here are her own and do not necessarily reflect agency policy.

5 responses

  1. yeah, I’m not really sure what the big deal is here. Does anyone not agree that gas is better than coal? Even with fracking (provided it’s properly regulated and not allowed everywhere), gas is far superior to coal both in traditional bottom line price and in climate & health potential. So… no rocket science needed there.

    Of course, gas is just a bridge to get us to truly clean energy, that’s the part Exxon will always leave out.

    1. No, Dave, everyone doesn’t agree that gas is “better than coal” in terms of greenhouse gas emissions.

      Did you read the article? Are you a troll?

      There is substantial evidence that the alleged overall advantage of natural gas over in terms of GHG emissions hinges entirely on drastic underreporting of methane leakage during exploration, production, and distribution.

      Moreover, money invested right now in expanding gas infrastructure – even if it were as “clean” as ExxonMobil wants you to think – would be much more effective if invested instead in true renewables – solar, wind, etc.

      Natural gas expansion is truly building a bridge to nowhere.

    2. Hi Dave, thanks for your comment. That’s exactly the problem: the benefits of natural gas compared to coal have pretty much been common knowledge for a long time, but what’s come to light more recently are indications of a significant downside to natural gas in terms of lifecycle greenhouse gas emissions, which could wipe out any advantage it has.

  2. Nice work on this article. I had been cautiously optimistic about natural gas until reading about the methane leakage problem in greater depth as well. If the Marcellus numbers are correct then one could hope with proper oversight *some* natural gas could be developed responsibly as a coal alternative… but that’s a pretty big “if”.

  3. There is no way you greenies could ever accept natural gas as an alternative to coal or any other fossil fuel. Your ideology will not allow it. So stop thinking about how clean it is or any other advantages of natural gas over coal, and start thinking of new reasons that natural gas is bad.

    Like that comment by Tina Casey below regarding the life-cycle greenhouse gas emissions, that’s a good start. Remember natural gas has a horrible beginning with fracking for example. Just think about all of the groundwater that has been contaminated by fracking, the water wells in rural communities that have been damaged, the ruined lives, the misery and destruction. And that’s just from fracking alone.

    And if natural gas gets too cheap it will destroy the entire wind and solar industries. We can never be global leaders in the Clean Tech industry if natural gas becomes too dominant. We’ll end up going back to fossil fuels all over again. Oh the humanity!

    So stop being swayed by this Exxon funded study. You’re being manipulated. Think, think about how bad natural gas is. Its bad. Oh its soooo bad.

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