Pressurized watter reactor

Pressurized watter reactors (PWRs) constitute the muckle feck o the world's nuclear pouer plants (notable exceptions being the Unitit Kinrick, Japan, an Canada) and are one of three types of light watter reactor (LWR), the other types being bylin watter reactors (BWRs) and supercritical watter reactors (SCWRs). In a PWR, the primary coolant (watter) is pumped under high pressure tae the reactor core where it is heated bi the energy released by the fission o atoms. The heated watter then flows to a steam generator where it transfers its thermal energy tae a secondary system where steam is generated an flows tae steam turbines which, in turn, spin an electric generator. In contrast tae a boiling watter reactor, pressure in the primary coolant loop prevents the watter from boiling within the reactor. All LWRs use ordinary watter as both coolant an neutron moderator.

Diagram o a Pressurized watter reactor

PWRs were originally designed tae serve as nuclear marine propulsion for nuclear submarines and were used in the original design of the second commercial pouer plant at Shippingport Atomic Pouer Station, Pennsylvanie, Unitit States.

PWRs currently operating in the Unitit States are considered Generation II reactors. Roushie's VVER reactors are similar to U.S. PWRs. France operates many PWRs tae generate the bulk o its electricity.

Key tae diagram

1. Reactor pressure vessel
2. Fuel assembly
3. Control rod (controls reactivity within the reactor)
4. Control rod drive mechanism
5. Pressurizer (for primary coolant loop)
6. Steam generator (inverted U-tube teep)
7. Feedwatter
8. High-pressure turbine
9. Low-pressure turbine
10. Generator
11. Exciter
12. Condenser
13. Cooling watter
14. Feedwatter heater
15. Feedwatter pump
16. Cooling watter pump
17. Reactor coolant pump
18. Generated electricity
19. Main steam line
20. Containment