Nuclear scientists in the United States say they have taken a crucial step towards obtaining high energy production from nuclear fusion reactions that can trigger a self-sustaining chain reaction.
The successful experiment of scientists at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in the United States could pave the way for clean nuclear fusion energy in the future that could help fight climate change.
In the experiment, scientists focused the lasers of the NIF – the size of three football fields – on a tiny capsule containing deuterium and tritium – different forms of the element hydrogen – producing extreme temperatures and pressures like those found in the heart of the Sun. .
Although the power generation only lasted 100 trillion of a second, the reaction generated more than 10 quadrillion watts of power that could help initiate thermonuclear fusion.
Once a fusion reaction is initiated, it releases subatomic entities such as alpha particles that interact with the surrounding hot plasma – the fourth state of matter – and heat it further.
The hot plasma releases more alpha particles, in a self-sustaining chain reaction called ignition – a process never fully realized until now.
In the new experiment, the results of which have not yet been published in a peer-reviewed journal, scientists at NIF report energy production of more than one megajoule – an agreed threshold for the onset of “the inflammation “, and six times the previous highest. energy reached.
“This is a very important step forward. The energy produced is greater than the output of any of the previous experiments, almost 25 times greater than any of the best previous attempts, ”said laser physicist Ravindra Kumar, who was not involved in the experience. The independent.
According to Dr Kumar, senior professor of nuclear and atomic physics at the Tata Fundamental Research Institute (TIFR) in Mumbai, the success of this experiment is the biggest advance towards nuclear fusion since attempts began in the 1970s.
“Obtaining experimental access to thermonuclear combustion in the laboratory is the culmination of decades of scientific and technological work spanning nearly 50 years,” said Thomas Mason, director of the Los Alamos National Laboratory.
“This enables experiments that will verify theory and simulation in the high energy density regime more rigorously than ever before and enable fundamental achievements in applied science and engineering,” Dr. Mason noted in a statement.
Compared to the fission reactions used in nuclear power plants, which involve the splitting of atoms to release energy, fusion forces hydrogen atoms together, producing a large amount of energy and limited radioactive waste.
Because of these characteristics of nuclear fusion reactions, they are seen as a potential way to generate clean energy in the future.
However, the fusion reactions proved difficult to control and no experiment produced more energy than was put into initiating the reaction.
Even though the current attempt still required more input energy than it took out, scientists at Imperial College London, who are analyzing the data from the experiment, said it was the first to reach the crucial “ignition” stage.
They say ignition would produce far more energy than ever before, paving the way for a “breakeven point,” where energy input matches output.
“This is crucial to unlocking the promise of fusion energy and allowing physicists to probe conditions in some of the universe’s most extreme states, including those just minutes after the Big Bang,” the professor said. Jeremy Chittenden, Co-Director of the Center. for inertial fusion studies at Imperial College London, said in a statement.
“Controlled fusion in the laboratory is one of the great defining scientific challenges of this era and it is a major step forward,” added Dr Chittenden.