|This article's factual accuracy may be compromised due to out-of-date information. (February 2013)|
Gas depletion is the inescapable result of extracting and consuming natural gas since it is a nonrenewable natural resource. The number of years of natural gas left can be roughly estimated by the ratio of proven natural gas reserves to the current consumption rate.
According to the Energy Information Agency, the world in 2005 had enough natural gas left for 60 years at current levels of production. However, the global rate of production is increasing and the relevance of worldwide figures is questioned[who?] since unlike oil relatively little gas is shipped across the oceans. If one compares proven North American reserves versus North American consumption, one gets only 11 years (reserves of 308 trillion cubic feet, annual consumption of 27 trillion).
Role of new technology
As new technologies for natural gas production are discovered, the world's ultimate reserves can grow. Although some predictions of ultimate reserve recovery include provisions for new technology, not every magnitude of breakthrough can be accurately accounted for.
More than half the increase in US natural gas production from 2006 to 2008 came from Texas, where production rose 15% between the first quarter of 2007 and the first quarter of 2008. This was mostly due to improved technology, which allowed the production of deepwater offshore and "unconventional" resources. An important new development was the horizontal drilling in a geologic formation known as the Barnett Shale, underlying the city of Fort Worth, which is a highly impermeable formation and difficult to produce by conventional means. Wells drilled horizontally rather than vertically through the formation enabled profitable gas production, and the Barnett Shale now produces 6% of US natural gas. Other shale gas formations in the lower 48 states are widely distributed, and are known to contain large resources of natural gas.
- "In 2010, the United States used 24.1 Tcf of natural gas." http://www.naturalgas.org/business/supply.asp further cites estimates of reserves (from multiple independent analysts) ranging from 2,632 trillion cubic feet (Tcf) of technically recoverable natural gas resources in the United States to as low as 1,451 Tcf.
- "92 years worth of natural gas is technically recoverable using ... today’s technology" http://energytomorrow.org/blog/a-paucity-of-scarcity/
- "International Energy Outlook 2008". Energy Information Agency. June 2008. pp. Chapter 3 – Natural Gas. Retrieved 2009-05-17.
- Reserves of 6,3000 trillion cubic feet, consumption of 100 trillion.
- "Is U.S. natural gas production increasing?". US Energy Information Administration. 2008. Retrieved 2008-09-08.