The dream of fusion made real with boron
Boron may have been the secret to nuclear fusion all along Metal Tech News Weekly Edition – April 8, 2020
Last updated 6/27/2020 at 5:44am
Hydrogen, boron and lasers could be the secret ingredients to the Holy Grail of energy – fusion.
A team of scientists in Australia have developed a method of creating fusion energy like that of the sun that utilizes a unique process first pioneered by Professor Heinrich Hora in the 1970s.
The company, aptly named HB11, uses an approach to fusion that does away with rare, radioactive and difficult fuels-as well as the incredibly high temperatures necessary for conventional fusion.
Instead, it uses hydrogen and boron B-11, and by employing a precise application of lasers to trigger a fusion reaction in the hydrogen and boron atoms, the dream of near-infinite sustainable energy becomes closer to reality.
Fusion has been the long dreamt but elusive theoretical solution to humanity's energy needs. It is the natural function that powers the sun and, in turn, provides the vast amounts of energy that allows life to flourish on Earth.
Unlike fission, which occurs from the splitting of an atom and the risks involved, fusion promises reliable, safe, low cost, green energy generation with no chance of radioactive meltdown.
The fusion process itself happens when the nuclei of two atoms are forced so close to one another that they combine, with the resulting merger releasing energy.
The difficulty of containing this process has eluded researchers for decades. If this reaction could be tamed in a laboratory, however, it would have the potential to deliver near-limitless electricity with virtually zero carbon emission.
So far, the easiest reaction to initiate in a lab is the fusion of two different isotopes of hydrogen, deuterium and tritium, with most fusion research to date pursuing this avenue.
Yet, the caveat of a deuterium-tritium fusion is that it works best at temperatures even hotter than the sun, over 27 million degrees Fahrenheit!
The typical method to harnessing this incredible feat is something called toroidal magnetic confinement, basically an incredibly powerful magnetic field roughly a million times stronger than Earth's is used to contain the insanely hot matter that is produced from the fusion reaction, called plasma.
Scientists have already achieved deuterium-tritium fusion at experiments in the United States (the Tokamak Fusion Test Reactor) and the United Kingdom (the Joint European Torus).
These experiments initiate a fusion reaction using massive external heating, and it takes more energy to sustain the reaction than the reaction produces itself.
However, the recent advancements with HB11 has done away with that extreme heat and has reportedly simulated a fusion reaction without the bells and whistles of the multi-billion-dollar projects currently ongoing.
The trick was lasers all along
When a hydrogen nucleus fuses with a boron-11 nucleus it produces a unique reaction, no neutrons are created.
However, a hydrogen-boron fusion is more difficult to trigger a reaction in because of this fact.
The solution presented by professor Hora and colleagues was to use a laser to heat a hydrogen-boron fuel pellet to reach the point of ignition temperature and with another laser, heat up metal coils to create the toroidal magnetic confinement to contain the resulting plasma.
The magnetic field required for a hydrogen-boron fusion would need to be extremely strong, about 1,000 times as strong as the one used in deuterium-tritium experiments.
However, the purpose of the laser is not to heat the materials. Instead, it is to speed up the hydrogen to the point where it collides with the boron to begin a reaction.
Professor Hora had to wait for this technology to come to fruition, to test his theory. This became possible when in 2018 new advances in laser technology won the Nobel Prize in Physics.
Called "chirped pulse amplification," this laser technology is what was needed to make his fusion vision possible.
The hydrogen-boron fusion reactor would then use very brief laser pulses, lasting only nanoseconds, to excite the hydrogen and create the dream of fusion.
"This is brand new," Professor Hora says. "10-petawatt power laser pulses. It's been shown that you can create fusion conditions without hundreds of millions of degrees. This is completely new knowledge. I've been working on how to accomplish this for more than 40 years. It's a unique result. Now we have to convince the fusion people – it works better than the present day hundred-million-degree thermal equilibrium generators. We have something new at hand to make a drastic change in the whole situation. A substitute for carbon as our energy source. A radical new situation and a new hope for energy and the climate."
He also explained that the energy generated using the hydrogen-boron would allow for a much smaller and simpler generator because it would convert directly into electricity. In contrast, creating power production using coal, gas, or nuclear requires heating liquids like water to drive turbines.
This direct conversion to electricity would remove the need for any kind of heat exchanger or steam turbine generators, as the 'alpha particles' generated would create an electrical flow that could be used and sent almost directly into existing power grids.
HB11 describes its "deceptively simple" design, as, "a largely empty metal sphere, where a modestly sized HB11 fuel pellet is held in the center, with apertures on different sides for the two lasers. One laser establishes the magnetic containment field for the plasma and the second laser triggers the 'avalanche' fusion chain reaction. The alpha particles generated by the reaction would create an electrical flow that can be channeled almost directly into an existing power grid with no need for a heat exchanger or steam turbine generator."
"You could say we're using the hydrogen as a dart, and hoping to hit a boron, and if we hit one, we can start a fusion reaction," HB11 Managing Director Dr. Warren McKenzie said, describing the difference in their process from conventional reactors.
This approach is a precision technique as opposed to current designs where everything is superheated in the hopes that a reaction will occur.
When the lucky hydrogen does fuse with a boron particle, the reaction throws off helium atoms whose lack of electrons means they are positively charged.
This is the charge that the device gathers as electricity.
Because of boron
Professor Hora said boron is a safer and more environmentally sound than the traditional fusion materials.
"Tritium is very rare, expensive, radioactive and difficult to store. Fusion reactions employing deuterium-tritium also shed harmful neutrons and create radioactive waste which needs to be disposed of safely. I have long favored the combination of cheap and abundant hydrogen H and boron B-11. The fusion of these elements does not primarily produce neutrons and is the ideal fuel combination."
As opposed to the rarity of tritium, boron is an abundant element found easily on Earth.
Boron naturally occurs as isotopes B-10 and B-11 with the latter making up roughly 80% of all natural boron.
It is also an important chemical element that is used in making glass, ceramics, cleaning products, bleaching agents and in the manufacture of insecticides.
One of its primary uses is as an ingredient in making insulation and in protective material used in nuclear reactors, as well as a key element in the production of bulletproof vests.
Among those applications, it is largely relied on in the glass industry with nearly 50% of all boron being used for glass related products in 2017.
Due to its chemical makeup, along with the infinitely abundant hydrogen, the versatile element may see a new home next to the clean energy contenders and in the future, we could have, amongst solar, wind, and hydro, a Boron powered future.