Two new promising fusion concepts

The first is newly developed Inductive Plasma Accelerator by Helion Energy. Here is the paper.

Helion Energy - Nuclear fusion by supersonic field reversed configuration plasmoids

A new device, the Inductive Plasma Accelerator, was employed to simultaneously form and accelerate two oppositely directed field reversed configurations (FRCs) where the relative velocity (600 km s−1) of the plasmoids was much larger than their internal thermal motion. Upon collision all of the FRC directional energy was observed to be rapidly thermalized concurrent with complete magnetic reconnection of the two FRCs. Upon merging, the resulting FRC was compressed to kilovolt ion temperatures exhibiting a configuration lifetime better than predicted by past scaling of in situ formed FRCs. With the improved FRC confinement scaling, a pulsed plasma device based on this approach capable of achieving fusion gain is examined. For an FRC with a poloidal flux 20 mWb or greater, the fusion energy yield per pulse exceeds the plasma energy for compression fields of 10 Telsa or more. The scaling is insensitive to the compression chamber radial scale, providing for the possibility of a very compact fusion neutron source.

Given the scaling and the desire to optimize at smaller radius and higher power density, it is worth determining the parameters of a device capable of a gain of five. From equation 10 the following values will yield such a gain:

length (s) 2 meters
Poloidal Flux 25 mWb
Compression fields 16 Telsa
Q (gain) 5 times more energy out than put in .

Two meter long reactor achieving net gain of five? Compare that to the size of ITER, which has no net gain!


The second adept: CrossFire Fusor, more detailed overview here.

Crossfire Fusor - Aneutronic Nuclear Fusion Reactor

The CrossFire Fusor is a nuclear fusion reactor that is a combination of electrostatic confinement and magnetic confinement forming penning traps, electrostatic acceleration, injection of charged particles through magnetic cusps, magnetic reconnection, electrostatic and magnetic lenses, intended mainly to produce fusion power for thrusting spacecrafts. The name Fusor is short for fusion reactor, and the name CrossFire is due to both confinement and injection is done three-dimensionally.

Advantages over other fusion approaches:
• Quasi-isotropic confinement means that plasma does not rotate in a toroidal path as happens in Tokamaks.
• Calculated charge-to-mass ratio (Coulomb/kg), means that plasma confinement does not fail as happens in Tokamaks.
• No inner grid for causing losses as happens in the Farnsworth-Hirsch Fusor.[11]
• No recirculation of electrons to cause excessive cusp losses and bremsstrahlung radiation as happens in Polywell.[14]
• No outrageous energy consumption, as is required by Tokamaks and Laser Fusion Reactors.
• Uncomplicated formulas to support its technical feasibility.
• Continuous operation, no losses caused by repeated startup as happens in Tokamaks, Polywell and Laser Fusion.
• Well-defined cycles of energy, that is, electricity generation, heat recovering, and propulsion.

This nuclear fusion reactor evolves an improved fusion energy apparatus, that can be used to generate electricity at high efficiency; to thrust a spacecraft at very high performance levels, at inexpressive radiation hazards, requiring insignificant shielding; relatively inexpensive and abundant fuel supply; having a scalability of size and power, easier engineering and maintainability.

And there is also another, third promising alternative - Polywell confinement fusion.
So why are we still wasting huge amounts of money on the "brute force" Tokamak approach, when there seems to be far better options available?