05.07.2009

Storage is required in order to meet high seasonable demand for natural gas (i.e. during cold winter months in Europe and the US). Since the system works more efficiently with a constant flow throughout the year, gas is put into storage during lower summer demand periods to be used during peak times. Storage is also used for balancing purposes and/or in times of supply disruption. Gas can also be taken out of storage during peak consumption times, since heating demand for natural gas during winter puts upward pressure on natural gas prices. Natural gas is most commonly held in inventory underground under pressure in three types of facilities: (1) depleted reservoirs in oil and/or gas fields; (2) aquifers and; (3) salt cavern formations. Depleted oil and gas reservoirs are the most commonly used underground storage sites. Pipeline companies rely heavily on underground storage to facilitate load balancing and system supply management. Most storage facilities, such as the Rough Field in the UK are used more for seasonal trading purposes (store gas when it is cheap and sell it when it is more expensive during winter) as well as for technical reasons to maintain the continuous flow in the pipeline. In addition, the European national transmission system can fail during very cold winter days so the Rough Field is maintained to overcome daily shortfalls if such occur

Storage tanks for LNG, more expensive and complex but safer than above-ground tanks

Underground Injection is the process by which disposal of waste byproducts of the oil and gas industry are injected or pumped into deep underground reservoirs through a wellbore.

All the necessary approvals for developing the oil or gas field have been obtained and development of the project is underway

Includes natural gas from deep wells, coalbed methane, tar, shale, tight sands and other sources that are more difficult and costly to develop than conventional sources. Indeed, tightening global oil supply, regional tightening in gas supply and demand growth have resulted in an ever increasing interest in the exploitation of unconventional hydrocarbons. The development of deepwater offshore fields and tar sands require prices of $60 – $80 a barrel to be viable

Unconventional hydrocarbons is a term that covers a wide-ranging array of resources, such as heavy oil, tight gas, shale oil, coal bed methane