To the scientists working within the teams supporting the candidates in the 2007 presidential election: For a nuclear energy without radioactivity or pollution!
December 8, 2007
By Jean-Pierre Petit, former research director at CNRS
Astrophysicist and physicist, expert in magnetohydrodynamics (MHD)
jppetit1937@yahoo.fr
Energy management, at the national and planetary level, is an important theme of the politics of all states. Nicolas Hulot positions himself as the "front line" of this ecological awareness campaign, emphasizing a climate change that seems to be taking shape and accelerating. This speech immediately refers to the modes of energy production. I have read his book. Unfortunately, apart from advocating an economy policy, a fight against waste, "energy austerity," there is nothing else in the few pages he dedicates to the subject, in terms of alternative formulas, than the classic recourse to wind and solar energy. Nicolas Hulot is perfectly aware that these alternative solutions are both very expensive and relatively inefficient, compared to the price of a kilowatt-hour from oil production. A cost, by the way, brutal, calculated without considering the consequences, the pollution involved. I think our country should create a research center on all new formulas to produce energy. This kind of activity would deserve a section of the ministry of research and technology. In this perspective, I would like to be able to present to competent activists the possibilities offered by aneutronic or weakly neutronic fusion. Let me explain. For everyone, fusion is exclusively the one of the mixture of the two heavy isotopes of hydrogen: deuterium and tritium, which produces neutrons, which "activate the surrounding structures." Professor Gilles de Genne has strongly questioned the fact that the superconducting system ensuring the magnetization in Iter could resist the effects of an unavoidable neutron bombardment. There is that, plus the cooling of the plasma by the removal of heavy nuclei from the wall, etc... It has long been known that there are fusion reactions that do not generate neutrons, such as the reaction Lithium7 + hydrogen H1, giving two helium nuclei, or Bore11 plus hydrogen H1 giving three helium nuclei. The first starts at a temperature of 500 million degrees, the second at one billion degrees. This second branch had never been considered until now, due to the temperature that must be created, which seemed to belong to ... science fiction. The Lithium-hydrogen branch has been used since the 1950s in ... hydrogen bombs. Therefore, in the core of a thermonuclear explosion, the temperature is about 500 million degrees. This is also the ignition temperature of the reaction, obtained by focusing the flux of X-rays produced by an A-bomb, acting as a match, a detonator. But we are far from industrial applications.
The deuterium-tritium reaction starts at 100 million degrees. This was achieved for a few seconds in the English Tokamak of Culham, this result serving as a basis for the expensive and very problematic Iter project. With such a formula, it would be completely excluded to consider this type of continuous operation, like a boiler, at the temperatures required for the Li-H and B-H branches (respectively 500 million and one billion degrees). It would be necessary to opt for an impulsive operation.
Now, this transition from continuous to impulsive operation has already been successfully carried out in our technology and has proven so effective that the old formula was immediately abandoned. This is none other than this technological mutation which has taken humanity from the steam engine stage to that of the internal combustion engine.
Therefore, it is in the logic of technico-science. And if I had to criticize the Iter project, apart from all the unresolved technical and scientific problems it carries, it would be "the steam engine of the third millennium." It would be much more profitable and logical to be able to consider an operation of the "internal combustion engine" type, with higher temperature excursions, which would allow choosing non-polluting fusion reactions and practically free of radioactivity, like those mentioned above; a nuclear energy without radioactivity or pollution!
Specialists who have studied this question all conclude that the best reaction would be the boron-hydrogen reaction. If this reaction is completely aneutronic, there are parasitic reactions that still produce neutrons, and this is also the case for the lithium-hydrogen reaction. But this production is much less important than in the deuterium-tritium branch. Compared to it, it is minimal. It can be qualified as "quasi-aneutronic."
Therefore, a new formula is emerging: that of an impulsive fusion generator.
1 - A Bore-hydrogen mixture is compressed. - Fusion reactions release energy. - A plasma at very high temperature is created, which expands. 2 - This expansion is carried out in a magnetic field, in a regime of high magnetic Reynolds number (where the plasma and the magnetic field are very closely linked). "The magnetic field is compressed." 3 - This results in the birth of an induced current, and the production of energy, which, with a simple transformer, can be extracted by "direct MHD conversion" and used on a network. This system was experimented by the Russians (Andrei Sakharov's team) as early as the 1950s. The efficiency is very good. 4 - Part of the energy must be stored in the equivalent of a "flywheel" (that of the internal combustion engine), which will be used to ensure the compression of the next fusion charge.
The most appropriate analogical qualification would be a "fusion diesel."
This is the principle scheme, long known. The compressor is of MHD type. This means that a very strong electric current, several tens of millions of amperes, is injected into a system, also long known, called a "liner," which tends to implode along its axis under the action of Laplace forces. Could one reach a temperature of one billion degrees with such a system? The positive answer was given by an American team in 2005, a work published in February 2006 by Professor Haines, director of the plasma physics laboratory of the Imperial College of Cambridge. This result was ... unexpected.
http://www.jp-petit.com/science/Z-machine/papier_Haines/papier_Haines.htm
At the Sandia laboratory, New Mexico, the students of Gérold Yonas, pioneer in the 1970s in the field of high power pulsed electricity, built what is called a "Z-machine." Why this name? Because a plasma is compressed "along the OZ axis." The scheme is extremely simple. Several tens of millions of amperes are passed through a cylindrical conductor (along the cylinder's generators). This power must be injected...