EXPERT VIEW: Thomas Fink, SCHOTT

In a time when nuclear power is under the microscope in the UK, it is more important than ever for builders and utility companies alike to analyse component selection in both new builds and refurbishment projects. Even seemingly small-scale components can have a significant impact on total cost of ownership and overall safety.

In nuclear power plants, smooth operation and overall safety are dictated by the sum of the durability and longevity of all parts. However, not all components in nuclear power plants are capable of delivering long-term performance and withstanding potential severe accident conditions. Component failure in a severe accident scenario can have catastrophic consequences, especially in the instrumentation and control (I&C) chain.

What should be done to establish best practices and make sure nuclear power plants incorporate the safest and most robust components possible? In July 2017, the International Atomic Energy Agency (IAEA) issued TECDOC report #1818 detailing recommendations for the “establishment of an international technical basis to be considered when assessing the electrical and I&C equipment’s reliable performance under severe accident conditions”. Such a basis would alleviate the potential issue of components being subject to conditions exceeding original design basis assumptions in severe accidents.

The good news is there are superior components already available. Glass-to-metal sealed electrical penetrations, which represent a far more robust alternative to polymer-sealed counterparts, are one example. Glass-sealed penetration assemblies have a 60-year qualified lifetime, require no maintenance, and have been tested to withstand extended exposure to high temperature and pressure levels observed in severe accidents. The ability of glass-sealed penetrations to match or even exceed the reactor lifetime results in lower cost of ownership by eliminating the need for replacements, contrary to polymer seals which can wear out in just 15-25 years.

Greater safety and longevity, reduced maintenance, and lower cost of ownership are a few of the key benefits that are realised when utilising the most robust materials and components available in nuclear power plants. In a time of new-build focus for nuclear projects, the UK has the opportunity to become a world leader in nuclear power with the right steps and mindful component selections.

For more information, visit: www.schott.com/nuclear-safety