Question

Which best describes fusion nuclear reactors?

They use rods containing uranium for fuel.
They are currently used for electricity in several highly populated countries.
They are used in some naval vessels, such as submarines.
They have been successful, but they are very expensive to operate.

Answer 1

None of those four is correct for fusion reactors.

Brief corrections:
- "Use rods containing uranium for fuel" — that describes fission reactors. Fusion uses light isotopes (typically deuterium and tritium), not uranium fuel rods.
- "Currently used for electricity in several highly populated countries" — not true: there are no commercial fusion power plants producing grid electricity yet.
- "Used in some naval vessels, such as submarines" — naval reactors are fission reactors, not fusion.
- "Have been successful, but very expensive to operate" — fusion has had successful experimental demonstrations, but it has not yet been made into a commercially successful power source.

A better description: fusion reactors are experimental devices (tokamaks, stellarators, inertial confinement, etc.) that try to fuse light nuclei (e.g., D–T) at extreme temperatures to release energy. Research is ongoing; commercial deployment has not yet been achieved.