A gas holder (or gasholder or gasometer, sometimes also gas bell) is a large container where natural gas or town gas is stored near atmospheric pressure at ambient temperatures. The volume of the container follows the quantity of stored gas, with pressure coming from the weight of a movable cap. Typical volumes for large gasometers are about 50,000 cubic metres, with 60 metre diameter structures. Gasometers tend to be used nowadays for balancing purposes (making sure gas pipes can be operated within a safe range of pressures) rather than for actually storing gas for later use.
Resources - Storage/Processing