Natural gas before the natural gas can be transported. Natural gas extracted from oil wells is called casinghead gas (whether or not truly produced up the annulus and through a casinghead outlet) or associated gas. The natural gas industry is extracting an increasing quantity of gas from challenging resource types: sour gas, tight gas, shale gas, and coalbed methane. There is some disagreement on which country has the largest proven gas reserves. Sources that consider that Russia has by far the largest proven reserves include the US CIA (47 600 km³), the US Energy Information Administration (47 800 km³), and OPEC (48
Natural Gas Choice Natural Gas Choice Natural Gas Choice programs in United States of America allow residential consumers and other small volume gas users to purchase natural gas from someone other than their traditional utility company. With Natural Gas Choice programs, customers can either purchase from their natural gas utility or choose to receive their gas supply from non-utility Choice suppliers. Large commercial and industrial consumers have had the option of purchasing the natural gas commodity separately from natural gas services for many years. Currently, 21 States and the District of Columbia have legislation or existing programs that allow Natural Gas Choice Programs.