Jennifer Granholm said then that the nuclear fusion experiment conducted by US scientists ha replicated some conditions found only in the stars and the sun: “Ignition allows us to replicate for the first time certain conditions found only in stars and the sun. This milestone brings us one significant step closer to the possibility of carbon-neutral fusion energy that powers the our society,” he stressed. Granholm continued: ‘If we can advance fusion energy, we could use it to produce clean electricity, transportation fuels, energy, heavy industry and so much more.’
Jill Hruby, US undersecretary for nuclear safety, commenting on the success of the experiment, said that the United States has undertaken “i first steps towards a source of clean energy that could revolutionize the world“. 192 high-energy lasers were used in the experiment. The “turning point”, a real “milestone” in the search for clean energy sources, took place on December 5, just over a week ago, when 192 giant lasers from the California lab’s National Ignition Facility bombarded a small cylinder the size of an eraser, containing a frozen hydrogen nucleus, embedded in a diamond.
It came to one “extraordinary example of what can be achieved with perseverance”, said Dr. Arati Prabhakar, director of the White House science and technology policy office, after recalling that it took “decades” and “generations” of scientists to achieve this result. It was, she added, an “incredible example of the power of American research and enterprise.”
According to nuclear fusion expert Stefano Atzeni of Rome’s La Sapienza University, it will take at least thirty years for nuclear fusion to go from being an experimental technology to a realitywith reactors capable of powering our cities with zero emissions: there are many technological challenges that still need to be overcome, both for inertial containment fusion with lasers (the one that led to the result obtained at the Lawrence Livermore National Laboratory in the USA) and for magnetic confinement fusion (the technique of the Iter reactor under construction in the south of France).
“Making predictions is really difficult, because we are just at the threshold of demonstrating that the inertial scheme works physically, while for the magnetic one we will have the proof from Iter in about fifteen years”, stated Atzeni. “The times will certainly be very long, at least thirty years for both routes, because there are still several challenges to overcome”. In the case of inertial confinement, more efficient lasers will be needed which can make not one shot a day but three or four shots a second, with energies of 100-150 megajoules each against the current 2.5. In the case of magnetic confinement “it will be necessary to develop increasingly reliable superconducting magnets in the long term and work on the extreme complexity of the tokamak, the donut-shaped ‘nuclear boiler'”, added the expert.