Is the EPR nuclear reactor just too complex?

EDF has once again delayed the start-up date for its under-construction Flamanville 3 (FA3) nuclear plant from 2014 to 2016, while raising the cost estimate to €6 billion ($8.5 billion) from €5 billion.

This is the third time that EDF has put back the commissioning date for FA3. Originally conceived as a five-year, €3.3 billion project when construction began in 2006, EDF admitted last year the plant would cost around €5 billion and be commissioned in 2014.

Areva’s Generation III design is the most complex pressurized water reactor ever devised. It has four independent emergency cooling systems each located in separate rooms away from the reactor building.

Simultaneous failure of the systems is almost impossible, claims Areva. In the event of a meltdown, however, the reactor core would be isolated by the reactor building’s dual-wall containment, which has one wall in pre-stressed concrete designed to withstand significant increases in pressure, and the second in reinforced concrete, known as the concrete shell.

These safety features are highly desirable following the catastrophic failure of the cooling systems at the Fukushima Daiichi plant in Japan in March, but the EPR is proving very costly and time-consuming to construct. Areva points to the progress in China, where construction of the first EPR at Taishan is on time and on budget, but with around 9000 Chinese workers working ten-hour shifts for seven days a week, perhaps that is not too surprising.

But the 3300 workers at Flamanville are reportedly being flogged too. According to the French trade union CGT, many of the 1000 foreign workers employed by Bouygues Construction at FA3 work between 10 and 15 hours per day, earning just €250 per month.

So even with cheap, hard-working labour at FA3, the project is five years late and 80 per cent over budget. Is there something inherently wrong with the EPR?

The EPR reactor at FA3, similar to the infamous Olkiluoto 3 project in Finland, which is due online four years later than scheduled and running 50 per cent over budget, requires twice as much concrete and electric wires, and four times more steel, than previous nuclear plants built in France.

While 80 per cent of the civil engineering work has now been completed and assembly of piping and electrical equipment has begun, FA3 has been dogged by welding and other civil engineering problems.

French nuclear regulator ASN has repeatedly highlighted the “inferior” quality of welds at FA3. Last year it found faults in welds of the containment liner – a metal barrier to ensure leak-tightness of the EPR reactor building – during an inspection.

EDF has also suffered a number of unfortunate accidents that have delayed construction. The deadly fall of a worker at the inner containment wall of the reactor building in January delayed work for nine weeks and is under investigation by authorities for possible manslaughter. Another worker plunged to his death in June, while a night-shift worker was killed recently in a car crash on his way home.

Even EDF admits that the EPR is more challenging to build than it had anticipated. Herve Machenaud, EDF’s power production and engineering chief, told Reuters: “In reality, construction conditions are far more complex and difficult, with far more demanding regulation, than it was the case 15 years ago, so we made an error of appreciation when we said we would know how to do that in 54 months.”

EDF is very confident that the new 2016 deadline will be met, but that must come as scant consolation to the French state-owned utility. As a first-of-a-kind reactor, EDF anticipated the EPR at FA3 would be late and over-budget. But perhaps not five years late and nearly €3 billion over budget.

With the UK wanting to renew its aging nuclear fleet with EPRs, the delay does nothing to reassure private investors in nuclear power. The complexity of the EPR pushes up construction risks, which in turn increases the cost of capital. With yet another delay at FA3, nuclear power just got even more expensive.