Query: ” ‘You see, gas in America is incredibly cheap, because of fracking,’ he says.

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Shale gas <=SEP=> Shale gas is natural gas that is found trapped within shale formations . Shale gas has become an increasingly important source of natural gas in the United States since the start of this century , and interest has spread to potential gas shales in the rest of the world . In 2000 shale gas provided only 1 % of U.S. natural gas production ; by 2010 it was over 20 % and the U.S. government 's Energy Information Administration predicts that by 2035 , 46 % of the United States ' natural gas supply will come from shale gas .   Some analysts expect that shale gas will greatly expand worldwide energy supply . China is estimated to have the world 's largest shale gas reserves .   The Obama administration believed that increased shale gas development would help reduce greenhouse gas emissions . In 2012 , US carbon dioxide emissions dropped to a 20-year low .   A 2013 review by the United Kingdom Department of Energy and Climate Change noted that most studies of the subject have estimated that life-cycle greenhouse gas ( GHG ) emissions from shale gas are similar to those of conventional natural gas , and are much less than those from coal , usually about half the greenhouse gas emissions of coal ; the noted exception was a 2011 study by Howarth and others of Cornell University , which concluded that shale GHG emissions were as high as those of coal . More recent studies have also concluded that life-cycle shale gas GHG emissions are much less than those of coal , among them , studies by Natural Resources Canada ( 2012 ) , and a consortium formed by the US National Renewable Energy Laboratory with a number of universities ( 2012 ) .   Some 2011 studies pointed to high rates of decline of some shale gas wells as an indication that shale gas production may ultimately be much lower than is currently projected . But shale-gas discoveries are also opening up substantial new resources of tight oil / `` shale oil '' .

Natural gas <=SEP=> Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane , but commonly including varying amounts of other higher alkanes , and sometimes a small percentage of carbon dioxide , nitrogen , hydrogen sulfide , or helium . It is formed when layers of decomposing plant and animal matter are exposed to intense heat and pressure under the surface of the Earth over millions of years . The energy that the plants originally obtained from the sun is stored in the form of chemical bonds in the gas .   Natural gas is a fossil fuel used as a source of energy for heating , cooking , and electricity generation . It is also used as fuel for vehicles and as a chemical feedstock in the manufacture of plastics and other commercially important organic chemicals . Fossil fuel based natural gas is a non-renewable resource .   Natural gas is found in deep underground rock formations or associated with other hydrocarbon reservoirs in coal beds and as methane clathrates . Petroleum is another resource and fossil fuel found in close proximity to and with natural gas . Most natural gas was created over time by two mechanisms : biogenic and thermogenic . Biogenic gas is created by methanogenic organisms in marshes , bogs , landfills , and shallow sediments . Deeper in the earth , at greater temperature and pressure , thermogenic gas is created from buried organic material .   In petroleum production gas is often burnt as flare gas . The World Bank estimates that over 150 cubic kilometers of natural gas are flared or vented annually . Before natural gas can be used as a fuel , most , but not all , must be processed to remove impurities , including water , to meet the specifications of marketable natural gas . The by-products of this processing include : ethane , propane , butanes , pentanes , and higher molecular weight hydrocarbons , hydrogen sulfide ( which may be converted into pure sulfur ) , carbon dioxide , water vapor , and sometimes helium and nitrogen .   Natural gas is often informally referred to simply as `` gas '' , especially when compared to other energy sources such as oil or coal . However , it is not to be confused with gasoline , especially in North America , where the term gasoline is often shortened in colloquial usage to gas .   Natural gas was used by the Chinese in about 500 BCE ( possibly even 1000 BCE ) . They discovered a way to transport gas seeping from the ground in crude pipelines of bamboo to where it was used to boil salt water to extract the salt , in the Ziliujing District of Sichuan . The world 's first industrial extraction of natural gas started at Fredonia , New York , United States in 1825 . By 2009 , 66 000 km ³ ( or 8 % ) had been used out of the total 850 000 km ³ of estimated remaining recoverable reserves of natural gas . Based on an estimated 2015 world consumption rate of about 3400 km ³ of gas per year , the total estimated remaining economically recoverable reserves of natural gas would last 250 years at current consumption rates . An annual increase in usage of 2 -- 3 % could result in currently recoverable reserves lasting significantly less , perhaps as few as 80 to 100 years .