TAE Technologies (formerly Tri Alpha Energy) is an American company based in Foothill Ranch, California, created for the development of aneutronic fusion power. The company's design relies on a field-reversed configuration (FRC), which combines features from other fusion concepts in a unique fashion.
The company was founded in 1998, and is backed by private capital. They operated as a stealth company for many years, refraining from launching its website until 2015. The company did not generally discuss progress nor any schedule commercial production. However, it has registered and renewed various patents. It regularly publishes theoretical and experimental results in academic journals with over 150 publications and posters at scientific conferences over the last five years. TAE has a research library hosting these articles on their website.
Video TAE Technologies
Organization
As of 2014, TAE is said to have more than 150 employees and raised over $150 million, far more than any other private fusion power research company or the vast majority of federally-funded government laboratory and university fusion programs. Main financing has come from Goldman Sachs and venture capitalists such as Microsoft co-founder Paul Allen's Vulcan Inc., Rockefeller's Venrock, Richard Kramlich's New Enterprise Associates, the Government of Russia, through the joint-stock company Rusnano, invested in Tri Alpha Energy in October 2012, and Anatoly Chubais, Rusnano CEO, became a board member.
Since 2014, TAE has worked with Google to develop a process to analyze the data collected on plasma behavior in fusion reactors. In 2017, using a machine learning tool developed through the partnership and based on the "Optometrist Algorithm" TAE was able to find significant improvements in plasma containment and stability over the previous C-2U machine. The results of the study were published in Scientific Reports. Ernest Moniz the former United States Secretary of Energy at the US Department of Energy joined the company's board of directors in May 2017. As of July 2017, the company reported that it had raised more than $500 million in backing. In November 2017, the company was admitted to a United States Department of Energy's Innovative and Novel Computational Impact on Theory and Experiment program which allowed the company access to the Cray XC40 supercomputer.
Maps TAE Technologies
Design
The Tri Alpha design differs from previous concepts in the way it stores the particles. Instead of an external magnetic field or similar arrangement, in their Colliding Beam Fusion Reactor (CBFR) the particles are injected into a field-reversed configuration (FRC), a self-stabilized rotating cylinder of particles similar to a smoke ring. The ring's field is created by the electrical current of the injected protons and boron fuel, and supported by electrons that are also injected into the FRC.
The FRC is held in a cylindrical, truck-sized vacuum chamber containing solenoids. It appears the FRC will then be compressed, either using adiabatic compression similar to those proposed for magnetic mirror systems in the 1950s, or by forcing two such FCRs together using a similar arrangement.
The design must achieve the "hot enough/long enough" threshold to achieve fusion. The required temperature is 3 billion C, while the required duration (achieved with C2-U) is multiple milliseconds.
Field-reversed configuration
Unlike other magnetic confinement fusion devices such as the tokamak, FRCs provide a magnetic field topology whereby the axial field inside the reactor is reversed by eddy currents in the plasma, as compared to the ambient magnetic field externally applied by solenoids. The FRC is less prone to magnetohydrodynamic and plasma instabilities than other magnetic confinement fusion methods. The science behind the colliding beam fusion reactor is used in TAE's C-2, C-2U and C-2W projects.
The 11B(p,?)?? aneutronic reaction
An essential component of the design is the use of "advanced fuels", i.e. fuels with primary reactions that do not produce neutrons, such as hydrogen and boron-11. FRC fusion products are all charged particles for which highly efficient direct energy conversion is feasible. Neutron flux and associated on-site radioactivity is virtually non-existent. So unlike other nuclear fusion research involving deuterium and tritium, and unlike nuclear fission, no radioactive waste is created. The hydrogen and boron-11 fuel used in this type of reaction is also much more abundant.
TAE relies on the clean 11B(p,?)?? reaction, also written 11B(p,3?), which produces three helium nuclei called ?-particles (hence the name of the company) as follows:
A proton (identical to the most common hydrogen nucleus) striking boron-11 creates a resonance in carbon-12, which decays by emitting one high energy primary ?-particle. This leads to the first excited state of beryllium-8, which decays into two low-energy secondary ?-particles. This is the model commonly accepted in the scientific community since the published results account for a 1987 experiment.
TAE claimed that the reaction products should release more energy than what is commonly envisaged. In 2010, Henry R. Weller and his team from the Triangle Universities Nuclear Laboratory (TUNL) used the intense High Intensity ?-ray Source (HI?S) at Duke University, funded by TAE and the U.S. Department of Energy, to show that the mechanism first proposed by Ernest Rutherford and Mark Oliphant in 1933, then Philip Dee and C. W. Gilbert from the Cavendish Laboratory in 1936, and the results of an experiment conducted by French researchers from IN2P3 in 1969, was correct. The model and the experiment predicted two high energy ?-particles of almost equal energy. One was the primary ?-particle and the other a secondary ?-particle, both emitted at an angle of 155 degrees. A third secondary ?-particle is also emitted, of lower energy.
Inverse cyclotron converter (ICC)
Direct energy conversion systems for other fusion power generators, involving collector plates and "venetian blinds" or a long linear microwave cavity filled with a 10-Tesla magnetic field and rectennas, are not suitable for fusion with ion energies above 1 MeV. TAE employed a much shorter device, an Inverse Cyclotron Converter (ICC) that operated at 5 MHz and requires a magnetic field of only 0.6 tesla. The linear motion of fusion product ions is converted to circular motion by a magnetic cusp. Energy is collected from the charged particles as they spiral past quadrupole electrodes. More classical collectors collect particles with energy less than 1 MeV.
The estimation of the ratio of fusion power to radiation loss for a 100 MW FRC has been calculated for different fuels, assuming a converter efficiency of 90% for ?-particles, 40% for Bremsstrahlung radiation through photoelectric effect, and 70% for the accelerators, with 10T superconducting magnetic coils:
- Q = 35 for deuterium and tritium
- Q = 3 for deuterium and helium-3
- Q = 2.7 for hydrogen and boron-11
- Q = 4.3 for polarized hydrogen and boron-11.
The spin polarization enhances the fusion cross section by a factor of 1.6 for 11B. A further increase in Q should result from the nuclear quadrupole moment of 11B. And another increase in Q may also result from the mechanism allowing the production of a secondary high-energy ?-particle.
TAE plans to use the p-11B reaction in their commercial FRC for safety reasons and because the energy conversion systems are simpler and smaller: Since no neutron is released, thermal conversion is unnecessary, hence no heat exchanger or steam turbine.
The "truck-sized" 100 MW reactors designed in TAE presentations are based on these calculations.
Projects
CBFR-SPS
The CBFR-SPS is a 100 MW-class, magnetic field-reversed configuration, aneutronic fusion rocket concept. The reactor is fueled by an energetic-ion mixture of hydrogen and boron (p-11B). Fusion products are helium ions (?-particles) expelled axially out of the system. ?-particles flowing in one direction are decelerated and their energy directly converted to power the system; and particles expelled in the opposite direction provide thrust. Since the fusion products are charged particles and does not release neutrons, the system does not require the use of a massive radiation shield.
C-2
Various experiments have been conducted by TAE on the world's largest compact toroid device called "C-2". Results began to be regularly published in 2010, with papers including 60 authors. C-2 results showed peak ion temperatures of 400 Electron volts (5 million degrees Celsius), electron temperatures of 150 Electron volts, plasma densities of 1E-19 m-3 and 1E9 fusion neutrons per second for 3 milliseconds.
Russian cooperation
The Budker Institute of Nuclear Physics, Novosibirsk, built a powerful plasma injector, shipped in late 2013 to TAE's research facility. The device produces a neutral beam in the range of 5 to 20 MW, and injects energy inside the reactor to transfer it to the fusion plasma.
C2-W/Norman
In March 2015, the upgraded C-2U with edge-biasing beams showed a 10-fold improvement in lifetime, with FRCs heated to 10 million degrees Celsius and lasting 5 milliseconds with no sign of decay. The C-2U functions by firing two donut shaped plasmas at each other at 1 million kilometers per hour, the result is a cigar-shaped FRC as much as 3 meters long and 40 centimeters across. The plasma was controlled with magnetic fields generated by electrodes and magnets at each end of the tube. The upgraded particle beam system provided 10 megawatts of power. In 2017, TAE renamed the C-2W reactor "Norman" in honor of the company's co-founder Norman Rostoker who died in 2014. In July 2017, the company announced that the Norman reactor had achieved plasma. The Norman reactor is reportedly able to operate at temperatures between 50 million and 70 million degrees centigrade.
Criticism
Since publishing in 1997, the Colliding Beam Fusion Reactor has been criticized for unworkable conditions that would be caused by overly fast relaxation time in highly nonthermal plasmas, leading to much less fusion gain than expected. The concept was also scrutinized for issues with inevitable energy loss due to frictional heating in the plasma that would lower the fusion gain below any practical value, an overly strong coupling of the ions through the electrons; and an equilibrium issue due to the elongated plasma geometry. TAE founders responded that the critics' simplistic calculations should be replaced by more precise Vlasov and Fokker-Planck equations and development in classical transport theory. The CBFR was evaluated by the Institute for Fusion Studies of the University of Texas at Austin in 2001. The report concluded that "the proton-boron colliding beam fusion reactor is not a viable concept unless technology capable of very high energy conversion efficiencies (no less than 84%) can be developed."
See also
References
Source of the article : Wikipedia
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