Pressurized Water Reactor

Reactor · 1957 · Rankine cycle

Year: 1957
Kind: Reactor
Efficiency: 33 % thermal to electric — a steam plant, limited by the steam temperature the fuel cladding allows.
Used In: About two thirds of the world's reactors, and every nuclear submarine.
Power Density: A gigawatt from a core the size of a room.
Cycle: Rankine

Materials

Uranium dioxide pellets in zirconium-alloy cladding, a steel pressure vessel 20 cm thick, boron carbide control rods, a concrete containment.

How It Works

Uranium fuel rods heat water held at 155 bar so it cannot boil; that water passes through a steam generator and boils a separate loop, which drives a steam turbine. Two loops, so the radioactive water never leaves the containment. Boron in the coolant and control rods regulate the reaction.

Inventors

Hyman Rickover Enrico Fermi

Equations

Half-Life Radioactive Decay Law Mass–Energy Equivalence Thermal Efficiency

Skills

Mixing and Placing Concrete

Elements

Hydrogen Uranium Boron Zirconium Oxygen

Referenced by

element

Boron Hydrogen Oxygen Uranium Zirconium

equation

Half-Life Mass–Energy Equivalence Radioactive Decay Law Thermal Efficiency

researcher

Enrico Fermi Hyman Rickover

skill

Mixing and Placing Concrete

Open on the Machines shelf — the interactive card, the filters, and everything alongside it.

From the Machines database in Notion, last edited 2026-08-16. This page is the row, rendered by the build; nothing on it is written by hand.