Hunterston `B´ advanced gas cooled reactor-development of electrical auxiliary system with station life

Construction of Hunterston B nuclear power station started in the late 1960s and the station commenced operation in 1976. The nuclear plant comprises two advanced gas-cooled reactors (AGR) providing steam at high pressure and temperature to two dedicated 660 MW steam turbine generators. From the time of commissioning, the operating history has been one of steady improvement in load factor, which was further enhanced by the start of on-load refuelling operations in 1983. This improvement has been achieved by the development and refinement of operation and maintenance procedures and by a steady process of modification to improve the performance and reliability of the reactor and conventional plant. These developments have necessarily involved the auxiliary power systems and equipment and the purpose of this paper is to describe the most significant of the changes made in this area of the power plant