EDF and China General Nuclear Corporation (CGN), the two companies set to build the UK’s Hinkley C nuclear power station, have just ‘sealed’ their twin reactors at Taishan, China – disregarding widespread fears that they are unsafe and may crack in operation.

The discovery has emerged in drone footage obtained by the Hong Kong-based China Free Press (see video, below), which found that the concrete shells surrounding the reactors have now been closed ruling out any future replacement of the vessels and heads. The news is causing alarm in Hong Kong which lies just 130km east of the Taishan plant.

The Taishan nuclear site near Chanxi is isolated and entry is strictly forbiden to all non-accredited persons. Little information on construction progress or safety is released by CGN and EDF, the two companies building the power station, or by Chinese authorities.

The two 1.75 GW reactors at Taishan are of the same ‘EPR’ design to be used at Hinkley C, and already installed at Flamanville in France, where both reactor vessel and head were found to suffer from severe metallurgical defects that could cause the reactor’s failure.

Areas of very high carbon in the Flamanville reactor vessel and lid, both forged at Areva’s Le Creuset works, have caused that reactor’s construction to be placed on what appears to be indefinite hold. France’s nuclear safety inspectorate, ASN, is demanding ever more tests to be carried out on these two key components.

The danger posed by the high-carbon anomalies is that the reactor vessel and head will become brittle, crack under pressure, and release large amounts of radiation into the environment.

The Flamanville project is already running at €10.5 billion, over three times its original €3.3 billion cost. Originally scheduled to be generating power in 2012, it is now scheduled to be operational only in 2020. The faulty components having already been installed, it is very possible that they would have to be removed and replaced adding further huge costs. So large, in fact, that the project would probably be abandoned altogether.

Do Taishan reactor vessels share the same problem?

It is widely believed that the twin EPR reactor vessels and heads at Taishan suffer from precisely the same defects as those in France. Following the discovery of the problems at Flamanville in April construction at Taishan was halted for an extended period – from mid-2015 until at least October.

The two reactors were expected to be operational in December 2013 and October 2014, according to a report in Power Technology, which stated: “The Chinese nuclear project is benefiting from the experience gained from the Finnish and French NPPs, with significant savings in cost and construction time.” Reports from the site indicate that the current completion target is 2018 “at the earliest”.

In April 2015 the South China Morning Post ran a report stating that the Taishan reactors had not been subject to tests before installation, and could therefore suffer from the same defect.

CGN Power spokesperson Wang Xiaofei stated on 18th May that Areva had performed a comprehensive review of the manufacturing process of the parts in the two units at the Taishan plant according to the requirements of the “relevant regulations”, and that nothing was found to be sub-standard.

However Wang said nothing of the non-destructive tests that the Chinese National Nuclear Safety Administration (NNSA) had ordered on the units last year – leaving open the possibility that some problems may have been detected.

Fears not yet dispelled

The Taishan EPR vessels and heads were not forged by Areva, but were instead made in China and Japan under Areva’s direction and using the identical manufacturing process, as reported by China Free Press.

The vessel for Taishan 1 was made by Mitsubishi Heavy Industries (Japan), which delivered the unit to site in 2011. Dongfang Electric Corporation (China) began to make the vessel in December 2009, and delivered it from its factory in Nansha, Guangzhou to Taishan on 22nd October 2014. 

Professor Woo Chung-ho, a Hong Kong nuclear energy expert and former senior scientist at Atomic Energy of Canada, told CFP of his surprise that a Chinese factory had forged the reactor: “I didn’t know China was able to produce a pressure vessel. This component is quite special, it’s large. Every step in the manufacturing process requires strict control. The welding of the pressure vessel is highly complex because it is very thick and must be able to withstand high pressure, raising serious safety concerns.”

Lai Kwong-tak, policy convenor of the Professional Commons think tank, added his own serious safety concerns: “Areva has repeatedly had problems with product quality, even falsifying quality control tests, which China completely overlooked when they received the components. It shows that China lacks real regulatory power and has always relied on safety measures carried out by the French.”

And as an anonymous nuclear energy expert told CFP: “No one takes money out of their own pocket in this kind of company. All funds are borrowed, whether from banks or bonds, so there’s interest on everything. No profit means money lost on interest. You can work out the massive sum they’re losing daily if you go back to the average amount of electricity the plant is projected to generate each day.”

So while the sealing of the Taishan reactors in their concrete shell might demonstrate that the vessels and heads were found to be completely sound, it could also reflect an economic decision to press ahead regardless of known problems.

A French nuclear engineer with over 20 years’ experience and who specialises in nuclear reactors confirmed to CFP that the Chinese operators had been anxiously pushing for construction to speed up, so that the plant could come into service next year. “They want the plant to be the first in the world to use third-generation nuclear technology”, he said.

Hinkley C fears

The Taishan project is being carried out by Taishan Nuclear Power Joint Venture Co (TNPJVC), in which CGN has a 70% stake, while EDF has 30%.

The same two companies are also at the heart of the UK’s nuclear ambitions. The Hinkley C nuclear plant with its twin 1.6GW EPRs is to be shared between EDF and CGN with 66.5% of the joint venture company and 33.5% respectively.

CGN is to take the lead at nuclear sites at Bradwell in Essex and Sizewell in Suffolk, taking 66.5% of the two projects leaving 33.5% for EDF. Instead of the EPR, CGN is looking to use its own (never built) ‘Hualong’ reactor design at these two locations.

The big question raised for the UK is whether EDF and CGN are ‘fit and proper’ to be conducting major nuclear power projects here based on huge taxpayer guarantees and electricity market subsidies when their joint operation in China remains so questionable and opaque.

Areva, the company due to forge the reactors for Hinkley, also looks like failing the ‘fit and proper test’. Last month it was found to have ‘falsified’ the safety certificates on 400 key nuclear components. Now the French government is forcing EDF buying the near-bankrupt company.

Oliver Tickell is Contributing Editor at The Ecologist.