Effective Power at the Flip of a Switch

Unlike intermittent energy schemes based on wind and sun, nuclear fusion offers the promise of useful power when you want it. And unlike the cash guzzling “government fusion” project ITER, private fusion is showing actual promise within a meaningful time span.

Several private ventures based in the UK, US, and Canada, demonstrate that multiple free-wheeling approaches to solving the critical problem of reliable electric power are more likely to achieve a useful result than the “intergovernmental committee approach” which tend to become corrupt budget-busting strung-out projects with no end.

TAE Technologies in southern California is one of the most successful private fusion enterprises in terms of raising investor capital. The TAE device pictured at the top of this page attempts to achieve fusion by producing plasmas at both ends of a tube, and accelerating the two plasmas toward a collision with each other. Beam injectors in the central chamber stabilize the plasmas in order to allow fusion reactions to occur.

Estimates for useful fusion from the TAE approach range from 2 years to 10 years.

Commonwealth Fusion Systems LLC is an MIT spinoff which claims to be on track to build a commercial fusion reactor by 2025 using Tokamak confinement using the SPARC reactor.

MIT and CFS intend to use “yttrium barium copper oxide (YBCO) high-temperature superconducting magnet technology” to form a magnetic field to contain a reaction in which deuterium and tritium (both isotopes of hydrogen) will be forced to fuse together under high pressure and temperatures of “tens of millions of degrees.” The entire donut-shaped reactor should be “about the size of a tennis court,” says CFS CEO Bob Mumgaard. But if it works as promised, the reactor should produce about 10x more energy than is required to ignite and maintain the fusion reaction within it, paving the way, says CFS, for “carbon-free, safe, limitless, fusion power.” 

At that point, MIT and CFS will begin constructing a full-scale “ARC” — which stands for “affordable, robust, compact” — power plant, possibly as early as 2025. 

Similar in concept to the International Thermonuclear Experimental Reactor (ITER) currently under construction in Southern France (with an expected operational date of 2035), MIT and CFS say their reactor will cost only a fraction of ITER’s expected $22 billion price tag. If they’re right, that would also make ARC cheaper to build than existing fission-based nuclear power plants, which can cost $23 billion and up. 


SPARC would be far smaller than ITER — about the size of a tennis court, compared with a soccer field, Mumgaard said — and far less expensive than the international effort, which is officially estimated to cost about $22 billion but may end up being far costlier. Commonwealth Fusion, which was founded in 2018 and has about 100 employees, has raised $200 million so far, the company said.


Canada’s General Fusion is taking another unconventional approach to achieving controlled nuclear fusion on Earth:

General Fusion’s technology combines elements of magnetic and inertial fusion. A pulsed-power source generates a plasma that’s injected into a cavity surrounded by liquid lead–lithium. Before the plasma can decay, pneumatically driven pistons compress the liquid metal over 20 milliseconds, heating the plasma inside to fusion temperatures. Whereas laser-driven inertial fusion requires a compression ratio of about 40 to 1 for break-even conditions, General Fusion’s technology should work at a 7:1 ratio, says Delage. The nearly perfect symmetry required for laser-driven implosions will be greatly relaxed as well.

Scheduled for completion by 2025, the device is expected to achieve power-plant plasma temperatures and attain 10% of the conditions, known as the Lawson criteria, needed for break-even. From there, General Fusion plans to build a machine at power plant scale.

General Fusion Reactor

Seattle’s Zap Energy is another unconventional take on controlled nuclear fusion.

Zap Energy’s “sheared-flow stabilized Z-pinch” process should yield electricity-generating reactors that are “orders of magnitude cheaper” than fusion reactors requiring magnetic coils, says Conway. Reactors producing 200 MW thermal power would also be very small compared with tokamaks, says CTO Brian Nelson. Any number of those modules could be located with common ancillary facilities, such as a plant for handling and separating tritium. Some modules could be shut down when solar or wind power can meet grid requirements, or for maintenance. Steady-state tokamaks, by contrast, would need to be operated continuously.

Zap Energy prototype.
Zap Energy’s device is designed to extend the lifetime of lightning-like Z-pinch plasma. Credit: Zap Energy

The Z-pinch has been pursued for decades, notably at Sandia National Laboratories’ Z machine. But the lightning-like plasmas at Z last only a few nanoseconds before being ripped apart by instabilities, says Nelson. Zap’s sheared-flow technology extends the lifetime to 20 microseconds by causing the current to flow between electrodes at different velocities across the radii of a cylindrical plasma. Zap power reactors, which the company says could be available this decade—Conway declines to be more specific—would be pulsed at a few hertz. A circulating liquid lead–lithium blanket would carry the heat to steam turbines while also breeding tritium and protecting reactor components from neutrons.

Over three years Zap has quadrupled the electric current through the Z-pinch plasma and is now less than a factor of two from the level needed for breakeven, says Conway. He and Nelson say their goal is to reach break-even in three years.


If societies are going to get serious about their futures, they must get serious about their future energy supplies. Wind and solar energy schemes are political ploys foisted on unintelligent and uninformed voting blocs who are incapable of understanding the technical needs of modern and future industrial societies. Nuclear fusion is still in the future, but it remains a theoretical possibility for large scale reliable and affordable power generation — something that intermittent forms of energy will never be capable of.

The only forms of electric power that will work for the future include nuclear (fission and eventually fusion), hydroelectric, natural gas, coal, and other hydrocarbons, and perhaps a number of “power from outer space” schemes which might be perfected over the next several decades.

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