The United States Department of Energy will announce on Tuesday an “important scientific advance” to finally achieve the long-awaited nuclear fusion, the same one that occurs in the Sun and that promises clean, inexhaustible, safe energy without dependence on carbon . As the British newspaper ‘Financial Times’ advanced on Sunday, California’s Lawrence Livermore National Laboratory (LLNL) may have overcome the great obstacle to making this energy profitable, by achieve, for the first time, a “net energy gain” in an experimental fusion reactor.
The biggest problem facing nuclear fusion reactors so far has been generating an amount of energy equal to or greater than that needed to start the fusion. Nuclear fusion occurs at extremely high temperatures (millions of degrees), in which the matter (hydrogen or helium) that is used as fuel is not liquid, solid or gaseous, but passes into a ‘fourth state’ called plasma. Plasma can only be confined in magnetic or laser generated containers. But to achieve this requires a large amount of energy, more than the reactor is capable of producing.
That has been, up to now, the great problem of fusion: achieving a positive energy balance that allows its industrial use. A key step on this path is to achieve greater than unity ‘fuel gains’, where the energy generated through fusion exceeds the amount of energy invested in running the reactor.
Now, with analysis of the results still ongoing, LLNL scientists have achieved what appears to be the first net energy gain from nuclear fusion. According to what was published, on December 5 the researchers would have achieved a net energy of 2.5 megajoules with a 2.1 megajoule laser. According to some sources, they could have reached 3 megajoules.
Last January, the researchers had already managed to achieve 1.3 megajoules with a 1.7 megajoule laser shot. In September it was repeated with an energy of 1.2 megajoules and now, finally, the limit has been exceeded to obtain more energy than the one used. A milestone that can mark the energy of the future. Currently there are several problems in the field of energy: the main current sources (coal, oil and gas) are limited and contribute to climate change; on the other hand, solar and wind energy are not capable of covering all the demand and are subject to weather conditions; Lastly, nuclear fission arouses suspicion in the population, in addition to creating waste that is difficult to handle. For this reason, nuclear fusion -which should not be confused with what is generated in current nuclear power plants, since it is the opposite process- would be the perfect answer.
Nuclear fusion reproduces what happens in any star, including our Sun. Energy is produced by the fusion of light nuclei, such as hydrogen, deuterium and tritium, contrary to what occurs in nuclear fission, which breaks them . For this reason, it reduces the problem of nuclear waste and since it is not a chain reaction, it is easier to control.
Fusion power advocates claim it is clean, which would help reduce carbon emissions and global warming; abundant —if it were the only energy source used, the world would last 30 million years—; It uses little land and does not cause serious accidents. The worst accident at a fusion plant wouldn’t even require an evacuation. And a catastrophe like that of Fukushima, which occurred after an earthquake in 2011 and where a person died, would never occur.