Natural Gas Storage

Natural gas storage has emerged in recent years as an essential tool in managing natural gas supply. Natural gas has been a seasonal fuel but it can be stored for an indefinite period of time. By enhancing supply reliability, natural gas storage has become an effective tool for managing gas costs and plays a vital role in maintaining the reliability of supply needed to meet the demands of consumers. These storage facilities can be located near centers that do not have a ready supply of locally produced natural gas or at the gas site.

Why to store natural gas?
Natural gas in storage serves as insurance against any unforeseen accidents, natural disasters, or other occurrences that may affect the production or delivery of natural gas. Also, since, the exploration, production, and transportation of natural gas involves a lot of time, and the natural gas that reaches its destination is not always needed right away, so it is injected into the storage facilities.

Earlier, Natural Gas storage was undertaken to serve only for transportation and then distribution, ensuring required supply of natural gas to places from where the demand surges. But in the present market scenario, in addition to serve this purpose, natural gas storage tanks are primarily used by various industries for commercial usage, for instance, storing the gas when the prices are low or storing it for the times when the supply fails to meet the demand (unforeseen supply disruptions).

Natural Gas Storage Facilities
Natural gas is usually stored underground, in large storage reservoirs. These underground storage facilities are reconditioned before injection, to create a sort of storage vessel underground. There exists three main types of underground storage:

Depleted gas reservoirs
Depleted reservoirs are those underground formations that have already been exhausted of all the natural gas that can be recovered. This leaves an underground formation, which is geologically capable of holding natural gas.

Salt caverns
Salt caverns are formed out of existing salt deposits. They are best suited for the purpose of natural gas storage as they do not allow the gas to escape unless specifically extracted. Salt caverns are smaller than depleted gas reservoirs and aquifers, however, deliverability from salt caverns is much higher than them.

Aquifers
Aquifers are the most expensive type of natural gas storage facility available. They are basically underground permeable rock formations that act as natural water reservoirs, but can easily be modified and used as natural gas storage facilities. This is done by developing infrastructure facilities, like, extraction equipments, pipelines etc.

Apart from underground storage, natural gas can also be stored in its liquid form, popularly known as Liquefied Natural Gas (LNG). Since, natural gas in this form is shipped and stored in liquid form, it takes up much less space than gaseous natural gas.