EFS’s Aneutronic Fusion Reactor Project
Electric Fusion Systems (EFS) has recently presented its in-lab successful aneutronic fusion experiment involving a new radiation-free energy technology which only releases a minimal part of hazardous neutrons. The experiment is performed by involving lithium proton, with helium energy output products.
In an interview with EE Times/Power Electronics News, EFS’s co-founders Ken E. Kopp and Ryan S. Wood revealed that their invention, which is still in patent phase, allows generating fusion chain reactions in a safe and sustainable way and explained that their Light Element Electric Fusion (LEEF) reactor is miniature sized so as to suit a wide range of applications. It has no critical mass and it can be produced in any factory. This technology also shows safety advantages as it has no special nuclear materials of concern and no high-level radioactive waste. Such noteworthy features allow reducing design, licensing, construction and safety costs for possible adoption.
The two co-founders also said: “We have set ourselves the goal of not only demonstrating and validating the technology with the scientific community but licensing the intellectual property to strategic industries to accelerate global adoption”.
The aneutronic fusion is performed by following a series of measurements involving fusion reactions through neutron detection, gamma spectroscopy and optics. As observed in optical spectra, dense plasma initiates proton-lithium fusion reactions (Figures 1 and 2).
Aneutronic fusion
So far, nuclear fusion experiments have mainly involved deuterium (one proton and one neutron) and tritium (one proton and two neutrons), which are isotopes of hydrogen. These elements have shown advantages on a reaction rate basis but their reaction produces an intense stream of very energetic neutrons and this exposes to radiological risk: the reactor must be surrounded by a concrete shielding to contain the damages.
The need for a less high-energy radiation has driven an in-depth research on laser technology, laser plasma interactions, and laser-accelerated particle beams. Such research has led to aneutronic nuclear reactions that produce less high-energy radiation.
But what is a proton? a proton is a hydrogen atom stripped of its electron; lithium (Li) is a light, non-radioactive element that is used in lithium-ion batteries and many other industrial applications. EFS believes the lithium-proton fusion reaction is the best option as it is able to generate no neutrons or radiation, it is clean and it provides a high-energy output.
EFS fusion reactor
EFS’s solution involves a cyclic induction process to harness the energy of fusion chain reactions as an electric arc. This passes through a plasma fuel resulting in direct conversion to electricity. The efficiency of the system is determined by the density of the plasma. This “fusion-plasma transformer” strongly relies on a super dense fuel.
The company believes that such solution will heavily cut the costs on electricity. The two speakers mentioned that “In the US, costs are around $100 per megawatt-hour (or 10 cents per kWh), and the advent of new clean technologies could reduce such costs”. They added: “Our prototype technology is an aneutronic fusion reactor capable of delivering tens of kilowatts of power, but scalable to megawatts. The plasma transformer is ~90% efficient at converting diamagnetic pressure to electricity.”
The EFS fuel operates in a supercritical fluid state. Ion temperatures are of the order of MeV resulting in significant chain reactions during each fusion cycle. The process is cyclic (100-1000’s of hertz) and the fusion energy is extracted at each cycle through magnetic induction (figures 4 and 5).
When fusion reactions occur in a chain reaction state, they create explosions of charged particles that are electromagnetically coupled to the reactor’s oscillating magnetic field, which is subsequently transformed into electricity. Basically, it’s a gain transformer that uses fusion plasma as its core. “This allows us to use efficient power electronics to collect the EMF and then regulate it as a switching power supply. So, the direct output conversion can be, for example, 800 VDC or 35 kilovolts AC,” said the speakers.
They added, “we have an arc that goes through these electrodes and that expands with the fusion reactions, and then creates a magnetic pressure and an electromagnetic force that we capture in a plasma core transformer. And these can be developed on a large scale in industry, replacing normal transformers. Then, once you’ve put the energy into the coil, you can use typical power conversion electronics to bring the power up to whatever AC or DC voltages and frequencies yet,at the same time you need some control electronics to modulate the reactions. Essentially, what we’re doing is using the nature of fusion plasma to couple directly to the magnetic field and transfer the energy (an electromagnetic force) into the surrounding inductor coils. Hence we have a gain core transformer dirven by burning lithium and that’s really the source of the energy that we’re generating.” It is straightforward hot fusion– E=Mc2.
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