In a PWR, through which component does heat transfer from the primary loop to create steam for the turbine?

• A. The reactor vessel directly.
• B. The gas blanket.
• C. The steam generator.
• D. The condenser.

Answer: (C)

In a PWR, the energy from the reactor core heats the primary coolant, but the water on the primary side stays under high pressure so it doesn’t boil. The transfer of that heat to produce steam happens in the steam generator, which is a heat exchanger between the hot primary loop and the cooler secondary loop. The primary coolant flows through the steam generator’s tubes and transfers heat to the secondary water on the shell side, causing the secondary water to boil into steam. That steam then drives the turbine. The condenser later cools and condenses the steam back to water, but steam generation occurs in the steam generator.