1. Fuel Cladding

The cladding encloses the radioactive material produced during nuclear fission and prevents it from escaping.

2. Reactor Pressure Vessel

Its 200mm-thick steel wall keeps cooling water containing a minute amount of radioactive material within the primary coolant circuit.

3. Containment Building

A 900mm-thick pre-stressed concrete structure with a 6mm-thick steel interior lining houses the reactor pressure vessel. The containment building can withstand the impact of a large commercial aircraft.

4. Nuclear Reactor Fuel Assembly

Each reactor includes 157 groups of 4-metre tall fuel assemblies, 61 groups of which each have 24 control rods. Each fuel assembly comprises 264 fuel rods and each fuel rod contains 271 fuel pellets. Each reactor core is therefore made up of 41,448 fuel rods and has a mass of about 80 tonnes.

The Primary Coolant Pump (RCP)

In the Pressurised Water Reactor design, the sealed water circuit cooling the nuclear reactor is called “primary-circuit”. The water flow is driven by 3 primary coolant pumps. A pump motor set is about 8 metres tall and uses about 6.5 MW of power, driving water at 6 tonnes per second.

The Pressuriser (PZ)

The hot primary circuit is pressurised at 155 bar by the pressuriser to inhibit any steam bubble. The pressuriser is about 13 metres tall and weighs 80 tonnes.

The Steam Generator (SG)

In a steam generator, the hot primary circuit water flows up from the bottom inside U-tube bundle and boils up the cooler "secondary circuit" water outside the top of U-tube bundle to generate steam. Each steam generator contains over 4,400 number of 21 metres tall nickel-chromium alloy U-tubes and has an empty weight of about 330 tonne. It produces about half a tonne of steam per second.