UK nuclear generator British Energy has revealed that boiler tube cracking at its Hunterston B and Hinkley Point B power stations is such that additional inspections are required at other reactors.
Having completed the inspection of unit 3 at Hinkley Point B, British Energy has discovered that the level of boiler tube cracking is “at the high end of the range previously experienced.” As a result, whilst the level of boiler tube cracking is not as extensive as that at unit 3 of Hunterston B, the results indicate that early inspections of unit 4 at Hunterston B and unit 4 at Hinkley B are required.
The output of these reactors has already been lowered and preparations are being made to shut down the units for the inspections and to undertake any repair work required.
However, the inspection and repair process is unlikely to be able to proceed in parallel at all three units and British Energy is not able to give an indication of when both units at Hinkley Point B and both units at Hunterston B will return to service.
In addition the difficulties associated with boiler tube cracking, British Energy has also revealed that it is currently investigating a significant leak in an underground cast iron pipe in the cooling water systems at Hartlepool. Repair work is underway and the company expects return both units to service in November. However, BE acknowledges that there is a risk that more extensive underground cast iron pipe work replacement will be required which may result in further delay in the return to service of both units at Hartlepool and may require work at its sister station, Heysham 1, one unit of which is already operating at reduced load pending investigations in to operating temperature anomalies.
Meanwhile, Dungeness B has encountered issues with the operation of its fuel route affecting both units which relate to construction of certain components of the fuel assembly. This is expected to result in extended refuelling outages this financial year. The company’s share price plunged by more than 20% at the news.