June 1, 2009

Nuclear: Realistic Simulation Assists in Nuclear Power Plant Certification

Tim Webb

Aging Nuclear Facilities Need Attention

Regardless of the type of reactor, an integral part of safety assurance is the mitigation of facility aging. Originally designed for 30- to 40-year operating lives, the systems, structures, and components (collectively known as the SSC) of nuclear plants can change with time or use. Some components simply wear out, corrode, or degrade. Instrument and control systems may become obsolete as newer technologies evolve. Complicating the issue further, the properties of critical materials may also change through heat and neutron irradiation.

Identifying and correcting such longevity issues can extend the operating license of a plant by several decades, which is why the upgrading of older facilities is now a major focus of nuclear regulatory bodies and plant operators everywhere. At the same time, the newest facilities are being held to the highest standards of quality to ensure a lifetime of safe operation.

"The structural integrity and operational management of nuclear facilities must be secured far into the future — whatever the type or age of the plant," says Wolfgang Hienstorfer, head of the department of structural analysis at TÜV SÜD ET, a leading global technical service corporation, located in Filderstadt, Germany.

Hienstorfer’s team independently tests, inspects, and certifies nuclear facilities for licensing by the German government. He is also chairman of the advisory group on nuclear facility aging management for Germany’s Nuclear Safety Standards Commission, as well as a technical consultant to the IAEA on nuclear facility aging. Many recommendations that he has developed during two decades of work at TÜV have been incorporated into existing international standards. "On behalf of the regulatory bodies, we encourage the power utilities to follow the latest relevant research findings, whether they are maintaining an older plant or designing and building a new one," he says.