reactor coolant system

The reactor coolant system is designed to remove thermal energy from the reactor and transfer it to a heat exchange system for the creation of steam, which is in turn used to drive a turbine for the generation of electrical power. The coolant system is comprised of three major sub-systems: the primary and secondary coolant loops; and the power generation system.


system overview

Reactor coolant loop overview (click to enlarge)The coolant system is separated into two closed loops: the reactor-side primary loop and the generation-side secondary loop. This minimises the transfer of radioactivity from the reactor to generation components. Radioactivity in the secondary loop may degrade sensitive turbine-assembly components and would lead to excessive detectable emissions from the vessel via externally-facing cooling systems.

primary coolant loop

The primary coolant loop is a closed-cycle system surrounding the reactor chamber that uses pressurised water to transfer thermal energy away from the reactor to the heat exchange. This process protects reactor chamber components by keeping their temperature within a manageable range.

secondary coolant loop

The secondary coolant loop receives thermal energy from the primary loop via the heat exchange. This energy is used to create steam, which generates the necessary pressure to drive a turbine. Once through the turbine, a Radiant Heat Sink Array (RHSA) condenses steam back to water so that it can be cycled through the system again. Like the primary loop, the secondary coolant loop is also a closed-cycle system.

generation sub-system

The power generation system incorporates a turbine which uses pressurised steam to drive an alternator assembly. The output of the alternator assembly is high-frequency AC power which is distributed by the Power Distribution Network (PDN).