Although it appears surprising that gas is put back into the ground after expending so much time, effort and money on extracting it in the first place, underground gas storage (UGS) plays an important role in the management of the gas supply chain. UGS has been used effectively for nearly a century to balance the mismatch in gas supply and demand. Its use continues to grow and with the advent of gas market liberalization, additional uses of UGS have been introduced. In several countries some 20–30% of the annual gas consumption is supplied through the use of UGS. This paper provides an overview of the most common use of UGS, the current status of UGS in the world and the main characteristics of the various types of facility: such as gas fields, aquifers and salt caverns. Aspects related to the planning and performance of gas storage facilities are also discussed.
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The UK became a net importer of natural gas in 2004 and by 2020 will import up to 90% of its requirements, leaving it vulnerable to increasing energy bills and risk of disruption to supply. New pipelines to Europe and improvements to interconnectors will meet some demand, but Government recognizes the need for increased gas storage capacity: this may be best met by the construction of underground storage facilities. Energy security has also raised the likelihood of a new generation of coal-fired power-stations, which to be environmentally viable, will require clean-coal technologies with near-zero greenhouse gas emissions. A key element of this strategy will be underground CO2 storage. This volume reviews the technologies and issues involved in the underground storage of natural gas and CO2, with examples from the UK and overseas. The potential for underground storage of other gases such as hydrogen, or compressed air linked to renewable sources is also reviewed.