Laser fusion is a type of nuclear fusion that uses lasers to heat and compress fuel pellets to the point of fusion. This process is also called inertial confinement fusion, as it relies on the inertia of the fuel to keep them from exploding before they can fuse.
Fusion is the reaction that occurs when two or more atomic nuclei join together, releasing a large amount of energy. This energy can be used to generate electricity, and laser fusion is one of the most promising methods for achieving this goal. There are also other methods including magnetic confinement fusion, which uses extremely strong magnetic fields to contain the plasma where fusion reactions take place.
The process of laser fusion begins with a fuel pellet that is typically a few millimeters in diameter. The pellet contains deuterium and tritium, two isotopes of hydrogen. These isotopes are fused together to create helium, releasing a large amount of energy in the process. It is said that 1 gram of D-T fuel equates to approximately 8 tons of oil.
To initiate fusion, a series of lasers are focused on the surface of the fuel pellet. The lasers heat the surface of the pellet, causing it to implode. As the pellet implodes, the pressure inside the pellet increases, reaching levels that are like those found at the center of the sun. This high pressure causes the deuterium and tritium nuclei to fuse, releasing a large amount of energy. The energy released by the fusion reaction causes the fuel pellet to explode. However, the explosion is very brief, lasting only a few nanoseconds.
The goal of laser fusion research is to develop a system that can produce a sustained fusion reaction repeatedly. This would require the ability to focus a large number of lasers on a very small fuel pellet, moving at Japanese bullet train speeds (360kph) and to heat the pellet to the point of fusion without causing it to explode prematurely.
If laser fusion can be successfully developed, it could provide a virtually limitless source of clean energy. Fusion reactions produce no greenhouse gases, and the fuel used in fusion reactions is abundant and easily accessible as it is available from seawater.
The laser fusion method is also the approach deployed by the National Ignition Facility at the Lawrence Livermore National Laboratory in the United States, which announced the world’s first successful laser fusion experiment in December of 2022. The net energy gain, or the act of gaining more energy than the input, was a pivotal moment for laser fusion as the technology shifted from being an experimental endeavor of researchers to now a quest for commercial viability of the laser fusion reactor.
Like with other fusion solutions, laser fusion is still not ready for commercial electricity production, but it has the potential to revolutionize the way we generate energy. With continued research, laser fusion could one day become a reality, providing us with a clean, safe, and abundant source of energy for the future.