Inertial electrostatic confinement

Inertial electrostatic confinement (often abbreviated as IEC) of a plasma can be achieved with electrostatic fields which accelerate charged particles (either ions or electrons) directly, in a confined space. Ions can be confined with IEC in order to achieve nuclear fusion.

The Farnsworth-Hirsch Fusor is a specific implementation of an IEC device which is popular, since costs for building a simple one can run between $500 to $4000 (in 2003 U.S. dollars). Other IEC devices include ion guns.

Due to the simple and relatively inexpensive nature of these devices many backyard, science fair, and university researchers are working on IEC class devices. They are able to observe reproducible, convincing evidence of fusion reactions, however, these devices are orders of magnitude from breakeven (the energy input far exceeds the energy output).

These devices produce harmful radiation (neutrons, gamma rays, x-rays), and require high voltages and could therefore be dangerous if proper care is not taken.

Experts argue whether an IEC fusion device is capable of breakeven. Some researchers in the field hope that the inefficiencies of the design could be overcome through optimized or hybird designs and the IEC could be a low-cost path to fusion.