Maintenance of Nuclear Power Plants. Non-Nuclear Components, Generic and I&C Equipments

In the boiler, the primary water heats up as it passes through the core (the site of the nuclear reaction), goes to the steam generators (SGs) where it transfers its heat to the water in the secondary circuit, which vaporizes, then the primary water returns to the core. The steam thus produced turns the turbine that drives the alternator, which generates electricity. Returned to the liquid state by the "cooling" circuit, the secondary water is reheated (water station) and returned to the GV (figure 2 on [BN3295] ). Water from the cooling circuit is taken from the natural environment, where it is either discharged (open-circuit unit) or cooled in an air cooler and reused (closed-circuit unit).

Note: 900 MWe units and their components are referred to as "900 units" and "900 components" for short. The same applies to 1,300 and 1,450 (or N4) units.