Nuclear fusion occurs when the nuclei of two light atoms combine to form a heavier atom, releasing large amounts of energy in the process. Fusion is the source of energy in active stars, including our sun, where massive amounts of hydrogen fuse to become helium and release radiation throughout the solar system. Fusion is one of the nuclear reactions harnessed by humans to create powerful weapons, in the form of the hydrogen bomb.
Nuclear fission, on the other hand, is the process of splitting an atom, releasing high energy particles, which go on to split more atoms in a chain reaction, using radioactive heavy materials like uranium. Fission produces less external energy than fusion, but is easier to initiate and control. All nuclear power plants currently in use are based on the uranium fission reaction.
Fusion reactors have successfully been built, using the tokamak design, where very high temperature plasma is contained in a magnetic torus. All the fusion reactors built to date have been experimental, and none has produced excess energy, as very high levels of power are required to ignite the plasma and maintain the electromagnetic bubble.
In 1989, two Utah electrochemists, Stanley Pons and Martin Fleischmann, announced that they had achieved cold fusion: fusion reactions which could occur at ‘normal’ temperatures. However, they made their announcements before any peer review of their work was performed, and no subsequent experiments by other researchers revealed any evidence of fusion.
Some researchers have continued to make experiments attempting to produce cold fusion, and have largely adopted the term Low Energy Nuclear Reactions (LENR) to avoid the negative connotations associated with cold fusion. None have reported verified success. Until now, that is.1952: Hydrogen bomb
The first detonation of a hydrogen bomb, code named Ivy Mike, yields 10.4 megatons out of a fusion fuel of liquid deuterium.1968: Tokamak
Results from the tokamak, a Soviet magnetic confinement device, which Igor Tamm and Andrei Sakharov had been working on, show the temperatures in their machine to be over an order of magnitude higher than what was expected by the rest of the fusion community.1989: Cold fusion?
Stanley Pons and Martin Fleischmann announce that they have achieved cold fusion. This is never verified.1997: JET success
The JET tokamak in the UK produces 16 MW of fusion power - the current world record for fusion power.2001: NIF begins
Building construction for the immense 192-beam 500-terawatt National Ignition Facility (NIF) project in the US is completed and construction of laser beam-lines and target bay diagnostics commences.2005: ITER
Following final negotiations between the EU and Japan, ITER (International Thermonuclear Experimental Reactor) chooses France for the site of the largest tokamak reactor. Construction is expected to take at least a decade.2009: NIF complete
Construction of the NIF at the Lawrence Livermore National Laboratory is reported as complete.2011: E-Cat
Inventor Andrea Rossi together with researcher Sergio Focardi from the University of Bologna claim to have successfully demonstrated commercially viable cold fusion in a device called an Energy Catalyzer.2012: E-Cat HT
The NIF performs several experiments with all 192 laser beams at full power, generating a pulse of 356 TW peak power. The construction of ITER is delayed, with completion expected only in 2018, or later.
Andrea Rossi submits his prototype E-Cat HT for testing in December. Despite some procedural problems, the results are positive, and verified by two other scientists.2013: E-Cat HT2
In March the E Cat-HT2, an improved design, is tested for excess heat production by a team of seven scientists. In May they publish their paper, reporting on both test experiments, and conclude that the device produces excess heat (over and above the input energy) that is at least one order of magnitude greater than conventional sources.
In July they begin a long term test experiment of the E-Cat over several months.2014: Fusion Future
The scientists publish their report for peer review. The results are unequivocal. The E-Cat device, charged with hydrogen-loaded nickel and secret catalysts, produces sustained heat at over 300C of 2KW while drawing only 350W of intermittent electric power. They cannot determine if the process is nuclear fusion, as they are not permitted to inspect the contents of the fuel core, but are happy to conclude that the energy produced is “off the scale of conventional chemical sources.”