Pellet Fuelling

Firing frozen fuel pellets deep into the plasma core keeps the density and reaction rate up — the main core-fuelling method for a reactor.

What

Injecting frozen fuel pellets into the plasma

Why

Gas puffing only reaches the edge

Benefit

Delivers fuel to the dense core

Feeds

The staged D–³He fuel mix

A burning plasma consumes fuel and must be continuously replenished, but simply puffing gas at the edge doesn't work well — the gas ionizes at the boundary and struggles to reach the hot, dense core where fusion happens. Pellet fuelling solves this by firing small pellets of frozen fuel at high speed so they penetrate deep before ablating, depositing fuel exactly where it is needed.

For Kronos MetroVolt, pellet fuelling maintains the high core density (n̄_e = 1.9 × 10²⁰ m⁻³) the design runs at, and it is the practical means of delivering the right mix of deuterium and bred helium-3 as the plant moves through its staged fuel cycle. Precise fuelling is also one of the levers the control stack and digital twin use to hold the operating point.