New life for Dungeness B

Getting older, and all the challenges that brings with it, is something everyone – and everything – has to deal with, writes Mathew Beech.

The thought crosses my mind as I return to Dungeness B – the nuclear power station that looks like its just been dropped into the salt marsh landscape in south Kent – almost 20 years after my previous visit.

The power station, which sits alongside the decommissioned ‘A’ plant, is in the midst of a £25 million maintenance programme.

But this is more than just a regulator MOT for a nuclear power station. During this outage, substantial upgrades are being undertaken, which should keep the plant in fit working order through to 2028, possibly as far as 2030.

This expected ten-year life extension to Dungeness B, as well as further extensions to EDF Energy’s wider nuclear fleet (Hunterston B and Hinkley Point B have already been granted an additional seven years) will be vital to keep the lights on in the UK.

With the £14 billion Hinkley Point C plant not expected online until 2023, getting the most out of existing power stations will be necessary to the continued provision of baseload power, as coal comes offline and the new Somerset plant gets up and running.

As I begin my tour, the first upgrade is obvious: the new flood defences that circle the plant. The wall, which is more than six feet high, is the outer layer of flood protection, should a 1-in-10,000 year event outflank the 25-foot high shingle bank that shelters the site from the English Channel. Workers are just putting the finishing touches to the wall, and putting up the obligatory health and safety signs as we wander past.

As we walk by the site offices, we round a corner to be greeted with what could be easily mistaken for a builder’s yard – flatbed lorries and scaffolding with people hurrying about, getting on with their jobs.

Now I really start to see what the maintenance and improvement comprises.

Regular checks are being carried out on fuses, pipes and wires on site, but much more substantial work is also being undertaken at Dungeness, the extent of which is revealed as I enter the turbine hall.

Where a huge pump and pipework should be, there is… nothing. Elsewhere, one of the turbine houses is shrouded by scaffolding and covered up. I’m told by my guide for the day, Jon Jaros – who has more than three decades’ worth of experience at Dungeness – that the turbines have been dispersed across the Midlands for specialist refurbishment. Jaros, tells me the turbine hall is usually thrumming with the sound of spinning turbines – whereas today it is quiet.

Quiet is a relative term, of course, and there is still plenty of sound as engineers scurry about, rushing to dismantle and reassemble the guts of the plant on day 21 of the scheduled 72-day maintenance period.

Entering the turbine hall is like stepping back in time.

There is heavy engineering that Isambard Kingdom Brunel would find familiar – heavy steel riveted in place, pressure valves, analogue dials – combined with more recently fitted digital readouts and shiny pipework.

I also see a few phones dotted about the plant under their 1970s covers, and complete with British Energy logos – another nod to the plant’s past.

But while elements of Dungeness B have been in situ since 1963, most of what is inside has been undergoing a constant evolution, and it needs to keep pace with the changing health and standards and operational guidelines.

An example of this is the monitoring equipment. Previously, if there was a fault, experienced engineers would have to manually hunt for the problem.

Now, in the switch room, there is a cabinet featuring a huge screen with a readout of all the parameters for the turbine – pressures, temperatures, etc – so now the engineers can pinpoint the problem immediately.

Station director Martin Pearson tells me: “It’s an old station in that it’s been operating for 30 years, but it will have the most modern computer brain in the fleet.”

Just before we make our way back through the plant, we visit the reactor hall.

It brings back memories from my visit as a schoolchild as I peer down from the viewing gallery to the huge floor hiding away the fuel and control rods. The only glimpse to what is below the floor can be had through the hatches – one of which is open with an engineer peering down into it.

Not much has changed here – but then not much can. The reactors are one of the two elements that ultimately will limit how long Dungeness B will be able to generate. The others are the boilers.

The graphite sleeves within them cannot be replaced, so when they’ve worn down, the station will have to close.

However, the work being carried out now includes checks on the graphite levels and the analysis of this will feed directly into the EDF Energy’s and the Office for Nuclear Responsibility’s decision on how long Dungeness will continue to operate.

But Pearson is keen to stress that the flood defence work, refurbishment to the turbines, and general maintenance work will not stop if and when the plant is granted that extra decade.

“If we do get lifetime extension in December, all we do is cross a line, because then we have to deliver a large portfolio of work to make sure the station remains at a modern standard,” he says.

“There are lots of modifications to do over the next ten-year period.

“So the hard work starts now.”