Centrica Issues UK Storage Alert
The UK’s largest but ageing gas storage facility, the offshore Rough field which accounts for about 70% of Britain’s storage capacity, may not be able to receive any new gas until the end of next winter.
Its owner and operator Centrica Storage (CSL) has concluded that "as a reasonable and prudent operator, based upon the results of its well testing program, Rough, cannot safely re-commence injection operations in the 2017/18 Storage Year" – so until April 2018.
CSL said April 12 it made this decision based on the results of the well testing programme to date which, due to the age of the asset, have “confirmed a number of different potential containment failure modes in a number of the wells.”
CSL said it will continue to provide withdrawal services in respect of the 2016/17 Storage Year (so until the end of this month). However that would not help those hoping to store gas there for this coming winter.
Rough is in the North Sea, gas is piped in and out via Easington on the coast (Map credit: Centrica)
Alternatives to Rough storage include the UK’s other smaller storage facilities, using storage outside the UK and importing via subsea interconnector pipelines such as IUK or BBL, stepping up LNG imports, and maximising production flows in mid-winter from Norway and the UK North Sea – but these could have limitations in an exceptionally cold winter.
There was a slight, but only slight, possibility left open by Centrica that partial injection may be allowed at a later stage this year, as indicated below.
CSL said it will continue to “conduct such further testing and analysis as it considers appropriate on a number of wells in order to allow CSL to make an assessment of the future pathway for commercial operation of the facilities. This will also be done in conjunction with further asset integrity work and assessments on the assets as a whole in order to ensure safe operations in the future beyond the Storage Year 2017/18.”
Last year CSL initially stopped all injections to and withdrawals from Rough, but in the autumn it allowed withdrawals from some wells only.
Data from National Grid showed that 4.1 TWh-gas (0.4bn m3) was stored in Rough at April 11, and that 20.8 GWh of gas was withdrawn that day.
In 2015 CSL reduced Rough's capacity to between 29 and 32 TWh-gas (2.7 and 3bn m3) from a historic previous maximum of 41 TWh (3.8bn m3).
The 30% of UK storage capacity still fully available is onshore at Aldbrough (where 0.2bn m3 was stored on Apr.11), Holford, Hill Top, Stublach, Humbly Grove, Hornsea and Holehouse Farm facilities.
Mark Smedley