ITER Objectives

ITER is a tokamak, in which strong magnetic fields confine a torus-shaped fusion plasma. The device´s main aim is to demonstrate prolonged fusion power production in a deuterium-tritium plasma. Compared with current conceptual designs for future fusion power plants, ITER will include most of the necessary technology, but will be of slightly smaller dimensions and will operate at about one-sixth of the power output level.

The programmatic goal of ITER is "to demonstrate the scientific and technological feasibility of fusion power for peaceful purposes". After extensive discussions with the scientific community at large, this general goal is now interpreted into a number of specific technical goals, all concerned with developing a viable fusion power reactor.

First of all, ITER should produce more power than it consumes. This is expressed in the value of Q, which represents the amount of thermal energy that is generated by the fusion reactions, divided by the amount of external heating. A value of Q smaller than 1 means that more power is needed to heat the plasma than is generated by fusion. JET, presently the largest tokamak in the world, has reached Q=0.65, near the point of "break even" (Q=1). ITER has to be able to produce Q=10, or Q larger then 5 when pulses are stretched towards a steady state. This is done so that, in the "burning plasma", most of the plasma heating comes from the fusion reactions themselves.

Secondly, ITER should implement and test the key technologies and processes needed for future fusion power plants - including superconducting magnets, components able to withstand high heat loads, and remote handling.

Lastly, ITER should test and develop concepts for breeding tritium from lithium-containing materials inside thermally efficient high temperature blankets surrounding the plasma.