Understand fusion energy the way the field actually works.

D-T is the near-term reference fuel

Deuterium-tritium fusion is widely used as the reference path because it reaches useful reaction probability at lower temperatures than the common alternatives. The tradeoff is that most reaction energy leaves as fast neutrons, so a plant needs serious blanket, shielding, material, and tritium-accounting systems.

Lithium blankets do more than catch heat

In D-T reactor concepts, the blanket is a multi-function machine: it absorbs neutron energy, protects sensitive structures, moves heat to the conversion loop, and aims to breed tritium from lithium so the fuel cycle can keep operating.

Different methods stress different engineering limits

Tokamaks and stellarators use magnetic fields to hold plasma away from walls. Inertial concepts compress a small fuel target for a tiny interval. Each route faces a different mix of plasma stability, repetition rate, materials, diagnostics, and power-plant integration questions.

Fusion energy must become usable electricity

A plasma gain result is not the same as grid power. A power plant still needs heat capture, coolant management, turbines or direct conversion, maintenance access, fuel processing, reliable magnets or drivers, and enough uptime to matter economically.

Reactor materials are a system problem

Fast neutrons can displace atoms, produce helium and hydrogen in materials, change thermal properties, and activate components. Start with the safe systems guide before treating any reactor headline as a build plan.

Open materials guide

Good readers separate milestone types

When reading a fusion headline, ask whether the result is a physics record, a subsystem test, a power-cycle demonstration, a fuel-cycle proof, or a power-plant integration result. That habit prevents hype from hiding the real progress.