California-based Lawrence Livermore National Laboratory has announced that for the first time ever, researchers have obtained more energy from a controlledfusion reaction than they put into it. Using the world's largest laser, scientists injected 2.1 million joules of laser light into the reactor and obtained 2.5 million joules of energy.
Lawrence Livermore National Laboratory has reportedly confirmed that a successful experiment was recently conducted at its National Ignition Facility, but said that analysis of the results is ongoing.
The US government has teased a "major scientific breakthrough" and will hold a press conference on 13 December.
Nuclear fusion works by forming helium gas through the collision of heavy hydrogen atoms, releasing large amounts of energy and mimicking the process that occurs naturally at the centre of a star like the Sun, which burns at around 27 million degrees Fahrenheit (15 million degrees Celsius).
Similar experiments have been carried out before, but Livermore's was the first to produce more energy than was used to create the experiment, meaning that scientists could theoretically usefusion as a source of energy.
Using the world's largest laser, comprising 192 beams and temperatures more than three times hotter than the centre of the sun, the researchers have for the first time enabled fusion fuel to generate more heat than they emit into it, achieving a net energy gain.
Although it is still far from a commercial reactor, this development is still considered an important step in the field.
It could represent a breakthrough moment for humanity in moving away from fossil fuels such as oil and coal to a completely clean energy source that does not pollute the air or cause damage to the landscape through mining or pipelines.
The ultimate goal, still, is to generate electricity in the same way that the sun generates heat, by pushing hydrogen atoms close to each other so that they combine to form helium, thus releasing enormous amounts of energy.
One cup of this substance could power an average-sized house for hundreds of years, with no carbon emissions.
In a world where demand for electricity is increasing and the environment is deteriorating,fusion is considered the 'holy grail' of energy.
It combines atomic nuclei to create massive amounts of energy, as opposed to the fission process used in atomic weapons andpower plants, which splits atomic nuclei into pieces.
Unlike fission, there is less risk of accidents or theft of atomic material in fusion.
Nicholas Hawke, chief executive of Oxford-based start-up First Light Fusion, described the potential breakthrough as a "game changer".
If confirmed, he said, the result would be a watershed moment for inertial fusion as a power generation technology.
We need clean base-load electricity, he said, and that is exactly whatfusion can provide. It has none of the disadvantages ofpower, no high levels or long-lived waste, no weapons-grade material and no risk of meltdown.
Dr Mark Weinman of Imperial College London said that so far, despite 70 years of research, no one had got more energy out of fusion reactions than they needed to put in, with the record being around 70 per cent (i.e. a net loss of energy).
This new announcement from Livermore Lab, if proven true, sets an extraordinary point in human history, he said, and the future could usher in an era of green, safe and largely inexhaustible forms of compact energy, without long-livedwaste.
