An inertial fusion power plant is intended to produce electric power by use of inertial confinement fusion techniques on an industrial scale. This type of power plant is still in a research phase.
Two established options for possible medium-term implementation of fusion energy production are magnetic confinement, being used in the ITER international project, and laser-based inertial confinement, as used in the French Laser Mégajoule and in the American NIF. Inertial confinement fusion (ICF), including heavy-ion inertial fusion (HIF), has been proposed as a possible additional means of implementing a fusion power plant.
The operation of an IFE reactor is in some ways analogous to the operation of the four stroke cycle of a petrol engine:
intake of the fusion fuel (microcapsule) into the reactor chamber;
compression of the microcapsule in order to initiate the fusion reactions;
explosion of the plasma created during the compression stroke, leading to the release of fusion energy;
exhaust of the reaction residue, which will be treated afterwards to extract all the reusable elements, mainly tritium.
To allow such an operation, an inertial fusion reactor is made of several subsets:
the injection system, which delivers to the reaction chamber the fusion fuel capsules, and at the same time the possible devices necessary to initiate fusion:
the container (hohlraum), intended to take the fuel capsule to a uniform very high temperature, mainly for laser and ion beam confinement techniques;
the "wires array" and its power transmission line, for z-pinch confinement technique;
the "driver" used to compress the fusion fuel capsules which, depending on the technique, can be lasers, an ion beam accelerator or a z-pinch device;
the reaction chamber, built upon an external wall made of metal, or an internal blanket intended to protect the external wall from the fusion shockwave and radiation, to get the emitted energy, and to produce the tritium fuel;
the system intended to process reaction products and debris.
Several projects of inertial fusion power plants have been proposed, including power production plans based on the following experimental devices, either in operation or under construction:
in the United States, the National Ignition Facility (laser confinement) and Z machine (z-pinch confinement) experiments
in France, the Megajoule laser experiment
in Japan (Osaka University), the KONGOH experiment (laser confinement)
Only the US and French projects are based on z-pinch confinement; others are based on laser confinement techniques.
In the magnetic confinement field, the 2nd phase corresponds to the objectives of ITER, the 3rd to these of its follower DEMO, in 20 to 30 years, and the 4th to those of a possible PROTO, in 40 to 50 years. The various phases of such a project are the following:
Burning demonstration: reproducible achievement of energy release
High gain demonstration: experimental demonstration of the feasibility of a reactor with a sufficient energy gain
Industrial demonstration: validation of the various technical options, and of the whole data needed to define a commercial reactor
Commercial demonstration: demonstration of the reactor ability to work over a long period, while maintaining the requirements for safety, liability and cost.
As of June 2006, Megajoule and NIF lasers were not yet in complete service. Inertial confinement and laser confinement fusion experiments had not gone beyond the first phase. Around 2010, NIF and Megajoule were planned for completion.
Livermore's IFE (LIFE) project was cancelled in January 2014.
