Natural Gas Storage
Natural gas is stored to meet seasonal demands and to insure against supply disruptions. It is usually stored underground in large storage reservoirs and can be stored indefinitely. It can also be stored as liquefied natural gas (LNG). Liquefied natural gas takes up much less space to ship or store than gaseous natural gas.
Underground storage facilities were originally created to meet seasonal demand increases. Seasonal demand requirements are referred to as base load requirements. Supply disruption protection is referred to as peak load requirements. Base load facilities are capable of holding enough gas for long term seasonal demand requirements. Peak load storage facilities are designed to have high deliverability for short periods of time to meet sudden, short term demand increases. The typical turn over rate for base load facilities is a year whereas peak load facilities have short turn over rates.
There are three main types of underground storage reservoirs: depleted gas reservoirs, aquifers and salt caverns. The most common form of storage is the depleted gas reservoirs because they are the cheapest and easiest to develop, operate and maintain. As the name implies they are those formations that have already been tapped of their recoverable natural gas.
Aquifers are underground porous, permeable rock formations that act as natural water reservoirs. They are the least desirable and most expensive type of natural gas storage facility and are usually used in areas without depleted reservoirs.
Salt caverns are formed out of existing salt deposits. Salt caverns are usually much smaller than depleted gas reservoirs and aquifers and can’t hold the volume of natural gas necessary to meet base load storage requirements. They are used for peak load storage. They are primarily located along the gulf coast and in the northern states. Typically, natural gas can be delivered much quicker from salt caverns than reservoirs or aquifers.
These storage facilities are valuable because they can be located near market centers that do not have a supply of locally produced natural gas. Traditionally, natural gas has been a seasonal fuel with highest demand during the winter for heat. However, with a recent trend towards natural gas fired electric generation, there is increasing demand in the summer months for air conditioning.
There are approximately 400 underground natural gas storage facilities located strategically throughout the United States. Gas in an underground storage facility is divided into two categories: working gas called top gas and cushion gas called base gas. Working gas is the volume of gas in the reservoir above the level of cushion gas. The working gas is the gas that is withdrawn and used. The cushion gas is the permanent gas left in the reservoir to maintain adequate pressure. Oil companies, like Western Pipeline Corporation, have a large inventory of cushion gas in storage throughout the country.
Bob Jent is the CEO of Western Pipeline Corporation. Western Pipeline Corp specializes in identifying, acquiring and developing existing, producing reserves on behalf of its individual clients.
Article Source: ArticlesBase.com - Natural Gas Storage