The U.S Department of Energy released a study conducted by the National Energy Technology Laboratory which found that U.S. liquefied natural gas (LNG) exports to Europe and Asia would significantly reduce global greenhouse gas (GHG) emissions. While it was previously known that increased natural gas usage could help the U.S. reduce its own GHG emissions, it is now also clear that exports of U.S. LNG can help reduce global emissions.
The analysis calculates and compares the life cycle GHG emissions for imported natural gas power in Europe and Asia versus regional coal power. The analysis is a cradle-to-grave life cycle assessment that begins with extraction of natural gas or coal and ends with electricity delivered to the consumer. The results include GHG emissions for both imported natural gas and regional coal using the global warming potentials of each from the 2013 Intergovernmental Panel on Climate Change.
The study models these four scenarios for two different geographies, Europe and Asia:
“Scenario 1: Natural gas is extracted in the U.S. from the Marcellus Shale, transported by pipeline to an LNG facility where it is compressed and loaded onto an LNG tanker, transported to an LNG port in the receiving country (Rotterdam for the European case and Shanghai for the Asian case) where it is re-gasified, and then transported to a natural gas power plant. It was assumed that the power plant is located near the LNG import site.
“Scenario 2: This is the same as Scenario 1, except that the natural gas comes from a regional source relative to the destination. In the European case, the source is Algeria, and in the Asian case, the source is Australia. It was assumed that the regional gas is produced using conventional extraction methods. The LNG tanker transport distance is adjusted accordingly.
“Scenario 3: Natural gas is produced in the Siberian region of Russia utilizing conventional extraction methods and is transported by pipeline to a power plant in Europe or Asia.
“Scenario 4: Coal is extracted in the region of study (Europe or Asia) and transported by rail to a domestic coal-fired power plant in China or Germany. This analysis models both surface sub-bituminous and underground bituminous coals based on U.S. extraction data.”
For most scenarios in both the European and Asian regions, the generation of power from imported natural gas has lower life cycle GHG emissions than power generation from regional coal.
On a 100-year basis, imported LNG used for power generation produces 25 to 61 percent less life cycle GHG emissions than coal for Europe. In Asia, imported LNG used for power generation produces 18 to 59 percent less life cycle GHG emissions than coal.
On a 20-year basis, there is high potential for imported LNG in Europe and Asia to have lower life cycle GHG emissions than regional coal – up to 57 percent less with LNG.
The analysis determined that the use of U.S. LNG exports for power production in European and Asian markets will not increase life cycle GHG emissions when compared to regional coal extraction and consumption for power production.