During the winter heating season when demand for natural gas can be as much as five times greater than in the summer, many gas companies use some type of natural gas storage. Pipeline operators, gas producers and some utilities use depleted oil and gas wells, salt caverns and other natural geological formations to store gas underground. These facilities are filled during the summer, when demand is lower, and are drawn down during the heating season.
An advantage of such storage is that the facilities can be located closer to areas where the gas will be used. Currently, almost 400 natural gas storage facilities operate in the United States, located in 28 different states.