UK energy company Centrica has decided to cease operations at its ageing Rough gas storage facility located in the Southern North Sea due to operational issues.
On April 12, 2017, Centrica plc’s subsidiary, Centrica Storage Limited (CSL), announced that it was assessing the future pathway for Rough’s commercial operations.
Following the assessment, the parent company said in a statement on Tuesday that CSL has now completed the wells testing program and has analyzed the results of this extensive program.
CSL has also completed a review into the feasibility of returning Rough to injection and storage operations and concluded that, as a result of the high operating pressures involved, and the fact that the wells and facilities are at the end of their design life and have suffered a number of different failure modes while testing, CSL cannot safely return the assets and facilities to injection and storage operations.
Furthermore, the company said, from a commercial perspective, an assessment of both the economics of seasonal storage today, and the costs of refurbishment or rebuilding the facility and replacing the wells, suggests that both pathways would not be economic.
As a consequence, CSL intends to make all relevant applications to permanently end Rough’s status as a storage facility, and to produce all recoverable cushion gas from the field, which is estimated at 183 bcf.
According to the company, Rough gas storage facility is the largest in the UK, able to meet approximately 10% of the UK’s winter peak day demand and representing more than 70% of the UK’s current storage capacity.
The Rough field is situated in the Southern North Sea, 18 miles off the coast of East Yorkshire. There are two offshore installation hubs called 3B and 8A where gas is injected and extracted through up to 30 wells, which have been drilled through the platforms down into the reservoir thousands of feet below the seabed.
Gas is extracted as a vapor offshore, before being sent via a 91cm (36inch) diameter subsea pipeline to the Easington gas terminal where the gas undergoes several separation processes.