Expert-level fusion energy covering plasma physics fundamentals, confinement methods, tokamak design, ITER, private fusion ventures, and the path to commercial fusion power.
D-T fusion: deuterium plus tritium produces helium-4 plus neutron plus 17.6 MeV. D-T preferred: highest cross section at achievable temperatures, around 100 million C. Lawson criterion: n times tau times T must exceed threshold for net energy gain. Q factor: fusion energy out over heating energy in, Q greater than 1 means ignition. Tritium breeding: lithium blanket produces tritium from neutron capture.
Tokamak: toroidal plasma confined by combined toroidal and poloidal magnetic fields. Plasma current: drives poloidal field component, generated by transformer action. Beta limit: ratio of plasma pressure to magnetic pressure, stability constraint. ELMs: edge-localized modes, periodic instabilities that erode plasma-facing components. Disruptions: sudden loss of plasma confinement, large energy deposition on walls.
ITER: international tokamak under construction in France, Q equals 10 target. DEMO: demonstration power plant following ITER, Q greater than 25, net electricity. Plasma-facing materials: tungsten divertor, beryllium first wall in ITER. Superconducting magnets: REBCO high-temperature superconductors in new designs.
Commonwealth Fusion: SPARC tokamak using high-field HTS magnets, compact design. TAE Technologies: field-reversed configuration, hydrogen-boron fuel target. Helion Energy: pulsed FRC approach, direct energy conversion. Inertial confinement: NIF achieved ignition in 2022, laser-driven approach.
| Pitfall | Fix |
|---|---|
| Confusing scientific and engineering breakeven | Q=1 is not commercially viable |
| Ignoring tritium breeding challenge | Tritium is scarce, must breed from lithium |
| Assuming tokamak is only path | Multiple confinement concepts under development |
| Underestimating materials challenge | 14 MeV neutrons cause severe radiation damage |