Predicting the contractual cost of unplanned shutdowns of power stations: An accelerator-driven subcritical reactor case study

This paper discusses analysis of the acute contractual cost of a failure to supply electricity from the perspective of power station owners. It presents a model for analysing the financial cost to an electricity supplier in the context of a national grid when a power station unexpectedly instantaneously shuts down. The model probabilistically samples historical market data and includes analysis of the impact on the system buy price of historic unplanned generator shutdowns. A case study is presented for a potential future nuclear power station concept, the Accelerator-Driven Subcritical Reactor (ADSR), in the UK market. The reliability of ADSRs is a key issue in their future development. The model is used to identify an upper limit on the amount an operator should be willing to pay for reliability improvements that mitigate unplanned shutdowns. The case study results are presented in a form that allows the reader to scale the cost of accelerator system failures for any capacity factor and coefficient of reliability, for a range of discount rates.