Nuclear energy without radioactivity or pollution
To scientists working within teams supporting candidates in the 2007 presidential election: For nuclear energy without radioactivity or pollution!
December 8, 2007
By Jean-Pierre Petit, former research director at CNRS
Astrophysicist and physicist, specialist in magnetohydrodynamics (MHD)
jppetit1937@yahoo.fr
Energy management, at both national and global levels, is a crucial issue in the politics of all states. Nicolas Hulot positions himself as the spearhead of ecological awareness, emphasizing a climate evolution that appears increasingly clear and accelerating. This discourse immediately brings into focus the methods of energy production. I have read his book. Unfortunately, aside from advocating policies of economy, anti-waste, and "energy austerity," the few pages he devotes to alternative solutions mention only the usual reliance on wind and solar power. Nicolas Hulot is fully aware that these alternatives are both extremely costly and relatively inefficient compared to the cost per kilowatt-hour produced by oil. Furthermore, this cost is crude, calculated without accounting for environmental fallout or associated decontamination. I believe our country should establish a research hub dedicated to all new methods of energy production. Such an activity deserves its own department within the Ministry of Research and Technology. From this perspective, I would like to present to competent activists the possibilities offered by aneutronic or weakly neutronic fusion. Let me explain.
For most people, fusion means exclusively the reaction between the two heavy isotopes of hydrogen: deuterium and tritium, which produces neutrons that "activate surrounding structures." Professor Gilles de Genne has strongly questioned whether the superconducting system responsible for magnetization in ITER could withstand the inevitable neutron bombardment. There is also the issue of plasma cooling through the removal of heavy nuclei from the wall, among other challenges. Long known are fusion reactions that do not generate neutrons, such as the reaction Lithium-7 + hydrogen H1, producing two helium nuclei, or Boron-11 plus hydrogen H1 yielding three helium nuclei. The first reaction begins at 500 million degrees, the second at one billion degrees. This second pathway had never been considered until now, due to the extreme temperatures required—seemingly belonging to science fiction. The lithium-hydrogen pathway has been used since the 1950s in... hydrogen bombs. At the core of a thermonuclear explosion, temperatures reach around 500 million degrees—precisely the ignition temperature, achieved by focusing the X-ray flux produced by an atomic bomb, which acts as a spark plug or detonator. However, this remains far from industrial applications.
The deuterium-tritium reaction ignites at 100 million degrees. This temperature was briefly achieved in the English tokamak at Culham, a result that served as the foundation for the expensive and highly problematic ITER project. With such a method, continuous operation—akin to a boiler—would be entirely ruled out at the temperatures required for the Li-H and B-H pathways (500 million and one billion degrees, respectively).
We should instead opt for pulsed operation.
Yet, transitioning from continuous to pulsed operation has already been successfully achieved in our technology and proven so effective that the older method was immediately abandoned. This technological shift is what propelled humanity from the steam engine era to the internal combustion engine era. Therefore, this is in line with scientific and technical logic. If I were to critically assess the ITER project, beyond all unresolved technical and scientific problems it carries, I would describe it as "the steam engine of the third millennium." It would be far more profitable and logical to develop a system resembling an "internal combustion engine," with higher temperature excursions, enabling the use of non-polluting, nearly radioactivity-free fusion reactions—such as those mentioned above:
- Nuclear energy without radioactivity or pollution!
Experts who have examined this issue unanimously conclude that the best reaction would be the boron-hydrogen reaction. Although this reaction is entirely aneutronic, there are some parasitic reactions that still produce neutrons, as is also the case with lithium-hydrogen. However, neutron production is vastly lower than in the deuterium-tritium pathway—negligible in comparison. One could describe this as "quasi-aneutronic."
Thus, a new concept is emerging: a pulsed fusion generator.
- A boron-hydrogen mixture is compressed. Fusion reactions release energy. A plasma forms at extremely high temperature and begins to expand.
- This expansion occurs within a magnetic field under conditions of high magnetic Reynolds number (where plasma and magnetic field are tightly coupled). "The magnetic field is compressed."
- This induces a current and generates electricity, which, after a simple transformer, can be extracted via direct MHD conversion and fed into the grid. This system was experimentally tested by the Russians (Andrei Sakharov’s team) as early as the 1950s. The efficiency was very high.
- Part of the energy must be stored—equivalent to a "flywheel" (as in an internal combustion engine)—to power the compression of the next fusion charge.
The most appropriate analogical term would be:
a "fusion diesel"
Here is the basic principle, long known. The compressor is of the MHD type. This means injecting a very strong electric current—several tens of millions of amperes—into a system also long known as a "liner," which implodes along its axis due to Laplace forces. Could such a system reach a temperature of one billion degrees? A positive answer was provided in 2005 by an American team, with the results published in February 2006 by Professor Haines, director of the Plasma Physics Laboratory at Imperial College, Cambridge. This result was… unexpected.
http://www.jp-petit.com/science/Z-machine/papier_Haines/papier_Haines.htm
At Sandia National Laboratories in New Mexico, students of Gerald Yonas—pioneer in the 1970s in high-power pulsed electricity—built what is known as a "Z-machine." Why this name? Because the plasma is compressed "along the OZ axis." The design is absolutely simple. Several tens of millions of amperes are passed through a set of...