Role of passive systems in advanced reactors

In this paper, the role of passive systems in advanced reactor designs has been discussed. With large scale deployment of nuclear power reactors in future, the safety requirements in terms of risk for these future reactors would be different and more stringent than the existing reactors. In fact, some of these reactors are proposed to be built inside a population zone without having an exclusion zone. To achieve the higher safety standards in terms of reduction of risk, passive systems could play an important role by eliminating the requirements of operators or external inputs for their operation. However, it may be difficult or impossible to incorporate passive systems extensively in large size reactors, but could be well fit into small and medium sized reactors. Passive systems have several issues including their reliability, which must be resolved before incorporation of them into advanced designs. These are discussed in this paper.