natural+gas

Natural gas is primarily composed of methane (CH 4 ). A small percentage of natural gas is made of ethane, propane, butanes, pentanes, and larger hydrocarbons; elemental sulfur, helium and nitrogen; carbon dioxide and water vapor.

The U.S. consumed 24 trillion cubic feet of natural gas in 2010.
 * 30% was for electricity generation
 * 28% was industrial use
 * 21% was residential use
 * 13% was for commercial use

Natural gas is most commonly found along with other fossil fuels, such as oil and coal. More recently, tight sands and shales have become economical sources of natural gas, thanks to new drilling and extraction techniques.





During crude oil drilling and refining, excess natural gas is either vented into the atmosphere, or burned in a gas flare tower. Reasons for this include the lack of storage or transportation infrastructure for the gas, and as a pressure relief safety measure during drilling. It is estimated that 5.3 trillion cubic feet of natural gas is burned off each year around the globe. This is the equivalent of almost one-fourth of the U.S. annual natural gas consumption, and is a contributor to anthropogenic carbon dioxide emissions.