Battersea gas holders

A gas holder (commonly known as a gasometer, sometimes also gas bell, though that term applies to the gas holding envelope alone) 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 gasholders are about 50,000 cubic metres, with 60 metre diameter structures. Gasholders 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.