The gas storage facility has to respond to the business requirements of commodity trading and thus has to be in a state of readiness at all times to either import gas from the national grid or export from the store to the grid. The company had recently upgraded its control and monitoring systems to ensure reliability and availability. The work was undertaken by Cougar Automation’s Hampshire Office, using the latest version of Wonderware InTouch provided by SolutionsPT.
The client is situated in the Weald Basin which is a major geological feature of southern England and northern France. Their operations are disposed across the region with an oil production and gathering plant at Weston Common, satellite well sites, interconnecting pipelines for the transfer of gas, oil and water, an oil pipeline to a rail terminal at Holybourne and a gas pipeline to Barton Stacey for gas import and export. The client’s 10 billion cubic feet underground gas storage facility was built as an extension to an existing on-shore oil production plant. The store operates by taking natural gas from the National Grid Gas Transmission System through a 27 km long, 24-inch diameter pipeline to the client’s oilfield. The gas is then pumped for storage into depleted oil reservoirs.
The original oil production and gathering plant at the client’s site has been in operation for over 25 years, whilst the gas storage facility commenced operations in 2005. Gas storage operations at the client’s site take gas from the grid when demand is low and resupply to the grid when the market demand is greater. The storage also provides valuable additional capacity to the system. The gas is compressed into the underground reservoirs from which oil has been extracted, the reservoir occurring naturally and being surrounded by impervious strata. When the gas is required it is drawn from the reservoir, conditioned in various stages to remove H2S, heavier hydrocarbons, water and particulates and then recompressed to feed into the national grid.