An effective means of natural gas peak-shaving and storage technologies: Underground gas storage

An effective means for natural gas peak-shaving will help maintain the high-efficiency operation of the arterial lines and guarantee gas supply security in natural gas grid. In view of this, based on the status quo of domestic natural gas peak-shaving and storage technologies, it was pointed out that the underground gas storage (UGS) is the most important and economic way for urban gas supply and peak shaving because of its many advantages like huge storage capacity, reliability and safety, low cost in storage and transportation, etc. In addition, it was also emphasized that UGS should be close to urban users or at least not far from the arterial lines and the oil and gas reservoir type UGS is the most economic one in comparison with other types. Meanwhile, this paper also introduced the UGS ground engineering and techniques and discussed the developing trend of new UGS technologies. On this basis, some proposals were presented for UGS projects and construction in China. a. The overall gas storage fraction should be kept increasing, besides the routine needs for peak shaving, if conditions permit, the fraction of emergency and strategic gas reserves should also be boosted. b. UGS targets and sites should be always optimally selected to reduce the cost of gas to and from storage and improve the UGS utilization efficiency. c. Gas pricing mechanism should be formulated as early as possible for peak-shaving gas supply to achieve commercial operation of UGS. Gas storage associated policies should be studied well to better adopt the way of seasonal variation in gas price. d. Pressure drops occur between the high pressures of the transported gas in arterial lines and those at gas distribution stations, where it becomes possible to build some LNG peak-shaving plants. e. LNG storage and liquefaction facilities should be increased by an overall arrangement of LNG terminals and LNG plants, thereby to fully satisfy the peak-shaving needs through the interaction and optimal operation of both LNG plants and UGS facilities.