Probabilistic Safety Assessment (PSA) Benchmark for Multi-Unit/Multi-Reactor Sites

Many nuclear power plants (NPPs), either of the same or of different types, designs, or age, are co-located on a single site. While operators and regulators recognize the potential for multiunit accidents, clearly demonstrated during the Fukushima-Daiichi accident in March 2011, past probabilistic safety assessments (PSA) of NPPs have only estimated the risk arising from damage to one single NPP at a time. This CRP will bring together experts from the Member States with water cooled reactor technologies to utilize, test and further develop their current (or planned) PSA methods and assumptions by conducting, and comparing results of, a meaningful benchmark exercise. The exercise will involve development of Multi-Unit/Multi-Reactor-Type PSA (from here on referred to as MUPSA), based on single-unit PSA available in Member States. The insights gained from the exercise may identify technology solutions to reduce those risk contributors that are specific to multi-unit effects.