The new third generation (EPR) nuclear reactor is being built in France and Finland and is also proposed in the UK. A similar design went into operation in South Korea in December 2016 – but it remains the only one running commercially worldwide. That could change soon, however, as Craig Morris explains.

Shin Kori 3 is the only EPR reactor yet finished, and it is currently offline (Photo by Korea Kori NPP, edited, CC BY-SA 2.0)

On the 10 March 2018, the day before the seventh anniversary of the nuclear accident at Fukushima, India ordered six EPR reactors from French manufacturer EDF. The company has yet to complete even one.

Back in September 2016, I wrote an overview of third-generation nuclear reactor projects. The European ones are called EPRs. A similar design from Westinghouse is called the AP1000, and Korea has a similar APR-1400. The design is considered more inherently safe and flexible than the second-generation reactors currently in operation – and, indeed, still being built.

At least one nuclear expert once also considered the design “unconstructable.” No 3G units were online at the time; all were behind schedule. But in December 2016, Shin Kori 3, an APR-1400, went into commercial operation and ran perfectly for all of 2017 after a few years of delay when it was discovered that some safety cables installed did not meet specifications. It is currently off-line for three months of planned maintenance, a particularly long timeframe possibly explained by the reactor’s newness.

But Shin Kori 3 remains the only third-generation reactor worldwide that has gone into commercial operation. Shin Kori 4, where improper cables were also installed, is now expected to go online this September.

The EPR going up in Finland is now expected to commence generation in May of 2019; French reactor developer EDF will even have to pay (additional) penalties if that deadline is missed. Meanwhile, the EPR being built in Flamanville continues to make headlines for faulty workmanship. Nonetheless, it is to be loaded with fuel this year and start ramping up in 2019.

China is the country to watch, however. It is the only one trying out multiple 3G designs. But the Chinese are also having trouble sticking to timetables. In February, fuel loading was suspended at Sanmen 1, an AP1000 reactor, for safety reasons. It was originally to be finished in 2014. The reactor still reportedly has time to go into full operation this year, however. Sanmen 2 could also follow this year, along with Haiyang 1.

EPR in China also seems faulty

The Chinese are also building two EPRs of French design: Taishan 1 and 2. They are now expected in 2018 and 2019, respectively. In December, Reuters reported that a cracked component was detected “during tests of a deaerator.” The specifics are unclear, but Areva, the firm that is building the EPRs (and was recently taken over by EDF to prevent bankruptcy), has a history of welding issues pertaining specifically to EPR. Welding flaws have also been reported at the Flamanville EPR – the only other one being built. However, another report from December claimed that Chinese welding techniques may have been the problem – and that the matter was known as early as 2012.

An unrelated issue also apparently affects EPR units currently under construction in Europe and China: insufficient steel quality. In December, excessive carbon content was reported for part of the containment vessel at Taishan 2 (in Chinese). The quality of the steel is very high for such a large object; the containment vessel goes over the entire reactor. The carbon content cannot exceed 0.22% for the EPR; in China, the figure was 0.302%, roughly a third above the limit. However, the Chinese report says that excessively high carbon content was detected on the top cover of steam generators; the containment vessel itself is not mentioned. That component was made in Japan for all EPR units.

It thus seems that steel of such high quality is hard to make regardless of the size, and both the Japanese and French have failed, which suggests that the world’s best engineers find the task daunting. In France, a compromise was reached last year: Flamanville can go into operation for now (whenever it is finished), but a new vessel must be provided by 2024 – at a cost of 100 million euros within a project budget of 10.5 billion, roughly three times the initial estimate.

The next two years will reveal whether France and China can produce the next generation of nuclear power plants. For the moment, mainly one thing seems clear: if you want a third-generation nuclear reactor, call South Korea.