AP1000 reactors ‘exceed’ US earthquake safety standards

Westinghouse said researchers also found its AP1000 structure provides a ‘significant reserve margin’ to ensure radiation is contained

Brian Kenety 28.10.2011

Přístavba dalších dvou bloků jaderné elektrárny v Temelíně s sebou přináší řadu problémů, na něž se bude muset vláda důkladně připravit. foto: © ČEZČeská pozice

Přístavba dalších dvou bloků jaderné elektrárny v Temelíně s sebou přináší řadu problémů, na něž se bude muset vláda důkladně připravit.

Purdue University researchers have determined that the structural integrity of the shield building containing the main components of the Westinghouse AP1000 nuclear power plant (NPP) — the model which the company hopes Czech utility ČEZ will choose when it expands its Temelín NPP — can withstand earthquake forces more powerful than US federal design requirements, a concern since the nuclear accident at Fukushima in Japan.

The study was conducted at Purdue University’s Bowen Laboratory, which is internationally recognized for structural testing of large-scale components. The large-scale experimental and computational benchmarking research at Purdue was funded by Westinghouse, and the findings will be submitted to the US Nuclear Regulatory Council.

“The benchmarked models were used to investigate and evaluate the behavior of the steel-composite shield building design subjected to different extreme design and beyond design-basis loading scenarios including aircraft impact, earthquakes, tornado, missile impact, etc.,” Michael Corletti, Director of New Plant Engineering at Westinghouse, said in a press release.

Westinghouse also said that the researchers determined that the AP1000 structure provides a significant reserve margin to ensure radiation is contained.

“Most importantly, the benchmarked computational models were used to demonstrate the performance, overall ductility, and the seismic design philosophy used for the AP1000 shield building design when subjected to safe-shutdown and then beyond design-basis earthquakes,” Purdue University associate professor Dr. Amit H. Varma, who led the research, is quoted as saying. Varma is Director of the Center for Structural Engineering and Emerging Technologies for Nuclear Power Plants.

All eyes on Temelín

Westinghouse completed the construction of the first two units at ČEZ-operated Temelín, which went online in 2002 and 2003, and is among three competitors to expand the nuclear reactor complex there. It has proposed its AP1000 model pressurized water reactor (PWR).

The winner of the estimated Kč 200 billion Temelín contract should be announced in 2013 with output from the two new Temelín reactors possible from 2021. Apart from US-based Westinghouse, the international companies competing for the deal are France’s Areva and a consortium of Russia’s Atomstroyexport and Czech nuclear industry supplier Škoda JS.

Areva’s EPR model has a capacity of 1,650 MW, compared with Westinghouse’s AP1000’s 1,150 MW and the 1,158 MW offered by the MIR-1200 from the Atomstroyexport consortium.