Science & technology UK (Commonwealth Union) – The energy crisis has had governments across the world scramble to find new sources of energy. The Russia – Ukraine war, together with high inflation have both pushed up the price and restricted the supply of energy, highlighting the need for a variety of sources of energy.
Researchers have hailed a ‘true breakthrough’ as a fusion reaction that has demonstrated the ability to produce more energy than that which was utilized to produce it.
For many decades, scientists have made many efforts to harness thermonuclear fusion, which is the power source of stars to produce energy.
Fusion is capable of generating vast amounts of clean energy by applying minimal resources, needing just a small amount of fuel and bringing about the production of limited carbon emissions. Once a fusion plasma is ‘ignited,’ it will carry on burning for as long as it is held in place.
Fusion reactions, however, have been hard to maintain and no fusion experiment had formed more energy than had been put in to get the reaction going on prior occasions.
During the press briefing held earlier this month, an announcement was made that a fusion experiment at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in the US was successful with this ‘holy grail,’ forming increased energy than the laser pulse that was applied to heat the fuel.
The energy in the laser pulse generated 2.05 megajoules which was similar to the energy of 2 Mars chocolate bars, or the equivalent to boil 6 kettles of water. The energy from the fusion reactions was 50% more than the energy of the laser pulse.
Imperial College London physicists are presently assisting in the analysis of data from the positive outcome of the experiment, which was carried out on the 5th of December. Imperial has also had over 30 PhD students that moved on to work at the NIF, where the College keeps strong connections with the facility, and others across the globe via the Centre for Inertial Fusion Studies (CIFS).
“This wonderful result shows that inertial fusion works at the megajoule scale which gives huge impetus to its development for a power source and as a tool for fundamental science,” explained Co-Director of the Centre for Inertial Fusion Studies at Imperial College, Professor Steven Rose.
Dr Brian Appelbe, a Research Associate in the Centre for Inertial Fusion Studies at Imperial College, says “As well as being a significant step towards fusion power, this experiment is exciting as it will allow us to study matter at temperatures and densities never previously reached in the laboratory. All sorts of interesting Physics can occur at these conditions, such as the creation of antimatter, and the NIF experiments will give us a window into this world.”
Fission is the nuclear reaction that is presently made use of in power stations which is the splitting of atoms to emit energy. Fusion instead forces atoms of hydrogen to join, forming a high level of energy, and, crucially, restricted radioactive waste.
There are 2 key ways researchers across the world are presently attempting to produce fusion energy. The NIF turns its attention on inertial confinement fusion, which applies a system of lasers to heat up fuel pellets forming a plasma, which is a cloud containing charged ions.
The fuel pellets contain ‘heavy’ versions of hydrogen, that have deuterium and tritium, which are simpler to fuse and emit higher energy, but the fuel pellets require heat and pressure to conditions seen at the center of the Sun, a naturally occurring fusion reactor.
When these conditions are fulfilled, fusion reactions emit many particles, such as ‘alpha’ particles, that engage with surrounding plasma and heat it up more. The heated plasma then emits more alpha particles and so on, in a reaction that sustains itself, known as ignition.
