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Greater U.S. shale gas production helps deliver a drop in U.S. carbon dioxide emissions

Americans have seen numerous benefits flow from increased production of natural gas from shale and other unconventional sources – from more jobs to greater revenue and economic activity.

But the benefits of shale gas development are not only economic – they are environmental as well, as findings from the International Energy Agency confirm. According to the IEA, greater use of natural gas instead of coal in the United States has contributed to a significant drop in overall U.S. carbon dioxide emissions.

This owes to the fact that natural gas produces up to 60 percent less carbon dioxide emissions than coal when used for electricity generation. Increased shale production has led to abundant natural gas supplies at affordable prices, which in turn have encouraged electricity generators to switch fuels. As a result, U.S. electricity generated from cleaner-burning natural gas was up about 3 percent in 2011, while electricity from coal was down 6 percent.

The IEA credits this ongoing shift as one of the factors contributing to a 1.7 percent decrease in U.S. energy-related carbon dioxide emissions last year.

This positive step for the United States is no one-time event. The trend has been building for some time. The IEA reports that since 2006, U.S. emissions have fallen by 430 million tons (7.7 percent), which it terms “the largest reduction of all countries or regions.” Compared to 2006, electricity generated by natural gas in 2011 was up close to 25 percent, while that from coal is down more than 10 percent.

Such findings are just the latest to counter claims that lifecycle emissions from shale gas production and use could be higher than those from coal. According to a recent study, the natural gas emissions estimates behind that premise – used by Robert Howarth and his colleagues at Cornell University, among others – are significantly inflated. Researchers conducting the study for America’s Natural Gas Alliance and the American Petroleum Institute analyzed data used to estimate emissions from more than 90,000 wells. They concluded that greenhouse gas emissions from natural gas production are as much as 50 percent lower than the Environmental Protection Agency estimates used by Howarth and others.

The proof of natural gas’ contribution to reducing U.S. emissions is clearly in the data. In an interview with the Financial Times, the IEA’s Fatih Birol labeled developments in the United States “a success story.”

To be sure, the IEA cites several other factors for the decline in U.S. emissions, including efficiency improvements as well as the economic downturn over the past few years. Globally, the IEA’s findings are different; worldwide carbon dioxide emissions increased more than 3 percent from 2010 to 2011, driven largely by growth in emerging economies. Such data underscore the importance of addressing global emissions growth while supplying the energy needed to fuel economic development.

But Dr. Birol and the IEA leave no doubt that the “technology making shale gas production viable” is one of the most important reasons for the United States taking the global lead in curbing emissions. The safe, responsible and innovative application of hydraulic fracturing technologies in our nation’s shale formations led to record U.S. natural gas production in 2011.

The latest ExxonMobil Outlook for Energy projects that by 2040, carbon dioxide emissions from the advanced economies of the Organization for Economic Cooperation and Development will decline 20 percent from 2010 levels. As the IEA numbers make clear, the shale gas revolution is helping the United States do its part.

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