Gas Storage is based on the principle of injecting gas into an under-ground reservoir during the summer months when gas demand is low, and taking it out of storage during periods of high demand in the winter. Kinsale Energy operated the first and, to-date the only offshore Gas Storage facility in Ireland
The Southwest Kinsale Gas Field was discovered in 1995 and was brought on stream as a gas production reservoir in October 1999. The gas reservoir is in the Upper Cretaceous sandstones covering an area of 1,200 hectares in size, 800 meters below the sea bed.
The field was redeveloped in October 2001, whereby gas could be taken from nearby offshore gas fields and put into storage in the Southwest Kinsale reservoir. Subsequently, in 2006 modifications were made to enable gas taken from the onshore network to be stored in Southwest Kinsale and the gas field was converted to a fully-fledged offshore storage facility with a storage capacity of 230 million cubic meters (1 cubic meter of gas is equivalent to about 10 kW-hrs of energy).
A decision was taken in 2016 to close the Southwest Kinsale storage facility and commence the sale of the cushion gas from the Southwest Kinsale reservoir (cushion gas provided the pressure support for the Southwest Kinsale storage service). The last of the storage gas was withdrawn from Southwest Kinsale reservoir in March 2017 and Southwest Kinsale currently operates as a gas production reservoir in which the remaining indigenous gas is produced.