The US Department of Energy's (DOE's) National Laboratory is set to announce a major scientific breakthrough on nuclear fusion energy on Tuesday, December 12. The milestone has been achieved by researchers at DOE's Lawrence Livermore National Laboratory (LLNL) in California. For the first time, scientists have successfully conducted a nuclear fusion reaction resulting in a net energy gain, according to media reports.
US Secretary of Energy Jennifer M. Granholm and National Nuclear Security Administration (NNSA) Administrator Jill Hruby will make the announcement at 10:00 am EST (8:30 pm IST) on Tuesday, according to the official website of DOE.
What is nuclear fusion?
A nuclear fusion reaction is a process in which two light nuclei merge to form a single heavier nucleus, and releases energy because the total mass of the resulting single nucleus is less than the added masses of the two original nuclei. Nuclear fusion reactions, which power the Sun and the stars, could one day serve as a cheap source of electricity, official sources told news agency Reuters.
In nuclear fusion, light elements such as hydrogen are fused together to form heavier elements.
The Financial Times was the first to report the experiment.
Net energy gain achieved through nuclear fusion for the first time
Nuclear fusion releases energy, and scientists at LLNL have achieved a net energy gain for the first time.
Scientists have been trying to achieve nuclear fusion since at least the 1930s. According to a Reuters report, the ratio of energy required to conduct the nuclear fusion reaction and produce energy needs to be about 100 times bigger to create a process producing commercial amounts of electricity.
The nuclei of two atoms need to be subjected to extreme heat of over 100 million degrees Celsius in order to achieve nuclear fusion. This will cause the two nuclei to fuse into a new larger atom. The process will release larger amounts of energy.
The breakthrough will pave the way for sustainable energy production
The breakthrough on nuclear fusion energy could lead to a source of "bountiful energy" in the future, a government official told The New York Times (NYT).
The scientific milestone involves the National Ignition Facility (NIF), which uses giant lasers to create conditions that simulate the explosions of nuclear weapons, The Financial Times reported.
The milestone at NIF will improve the ability of the US to maintain its nuclear weapons without nuclear weapons, the NYT report said. Also, one day, scientists might be able to use nuclear fusion as a source of carbon-free energy.
Researchers have generated more energy out of a nuclear fusion reaction than they put in. This could help unlock a "near-limitless, safe, clean" source of energy, according to a report by The Guardian.
Researchers at NIF have managed to release 2.5 megajoules of energy after using 2.1 megajoules to heat the fuel with lasers, the report said, citing the Financial Times. However, the feat is yet to be confirmed officially.
Quoting Dr Robbie Scott, who contributed to the research, the Guardian report said the seminal result from the NIF is the first laboratory demonstration of fusion 'energy-gain', where fusion energy is generated more than the input by the laser beams.
However, experts believe that there is a long way to go before the technology could be scaled up. Professor Jeremy Chittenden, professor of plasma physics at Imperial College London, said to turn fusion into a power source, researchers will need to boost the energy gain still further.
Nuclear fusion consumes vast amounts of energy, but researchers at LLNL have made the process self-sustaining, the Reuters report said. The process will be carried out continuously instead of being conducted for brief moments.
The generation of carbon-free electricity by scaling up nuclear fusion could help fight climate change.
However, some challenges to the process are that the heat generated needs to be contained economically, and lasers must be fired consistently.
More about nuclear fusion and its importance
Einstein's famous equation, E=mc² states that mass and energy are interconvertible, and can explain the process of nuclear fusion, according to the DOE.
While fusion can be carried out using different elements in the periodic table, scientists are especially interested in the deuterium-tritium (DT) fusion reaction because this creates a neutron and a helium nucleus, and generates much more energy than most fusion reactions. Deuterium is a hydrogen isotope with two neutrons, and tritium is a hydrogen isotope with three neutrons.
The advantages of a DT reaction are that it generates large amounts of energy, and can be conducted at lower temperatures than other elements.
According to the International Atomic Energy Agency, nuclear fusion can generate four times more energy per kilogram of fuel than nuclear fission, a process in which a larger nucleus is split into two smaller nuclei. Nuclear fusion can generate nearly four million times more energy than burning oil or coal.
Since deuterium can be extracted inexpensively from sea water, and tritium can be produced through the reaction of neutrons generated through fusion with naturally abundant lithium, nuclear fusion will be an environmentally friendly process. Not only is fusion fuel plentiful and easily accessible, but would last for millions of years.
It is believed that future fusion reactors will be intrinsically safe and are not expected to produce high-activity or long-lived nuclear waste.
Since nuclear fusion is difficult to start and maintain, there is no risk of a runaway reaction. In other words, nuclear fusion can occur only under strict operational conditions. In case of a system failure or an accident, the plasma, which consists of a gas of ions and free electrons, will naturally terminate, lose its energy quickly, and extinguish before the reactor is damaged.
One of the biggest advantages of nuclear fusion is that it does not emit carbon dioxide or other greenhouse gases into the atmosphere.