In response to fast rising wholesale gas and power prices feeding through to extremely high consumer bills, (winter 22/23 wholesale electricity prices are currently forecast to be in the region of £600 per MWh) and the sharp focus on security of supply owing to the Russian invasion of Ukraine, EDF is to review the case for a ‘short extension’ of its Hartlepool and Heysham AGR nuclear power plants to continue generating beyond the current scheduled closure in March 2024.

All of this is happening at a time of significant change for the UK’s nuclear fleet as older stations move into the defuelling stage. EDF’s commitment has come in a strategy update for its UK nuclear fleet.

French state-owned EDF says that to boost energy security it was seeking to ‘sustain as much output as possible from the 5.5 GWe of generating capacity available at Heysham 1, Hartlepool, Torness, Heysham 2 and Sizewell B’ power plants. Hartlepool, on Teeside in the northeast of England, and Heysham 1 in Lancashire in northwest England, are among four of seven AGRs in the UK fleet  which continue to generate electricity, and are due to continue doing so until March 2024, which would represent 41 years of operation.

EDF points out that the end of life of these stations depends on assessments of the condition of the graphite making up the reactor cores, and the plants’ ability to meet external regulations, for example global earthquake regulations. But "In light of the severity of the energy crisis and the results of recent graphite inspections, EDF will look to review the case for a short extension for Heysham 1 and Hartlepool to generate beyond the current forecast of March 2024. This will depend on the results of graphite inspections over the coming months. It is important that preparations for defuelling continue so that if the stations do end generation in the next 18 months we are operationally ready to start defueling."

EDF says that it aims to invest £1.0 billion in maintenance, inspections and plant upgrades to help sustain output for 2023 to 2025 and will review the case to extend generation at Hartlepool and Heysham "within the next few months".

It also said it was working on a 20-year extension for Sizewell B, which is currently scheduled to generate power until 2035.