Fusion energy is the process that ‘powers’ the stars, including our sun, making all life on Earth possible. As our planet’s need for a sustainable solution to global energy increases, scientists are putting more effort into researching the ways that in can be created. Fusion energy is produced by fusing light atoms, such as hydrogen, at the extreme temperature and pressure existing in the center of the sun. At this heat all gases turn to plasma, which is the fourth state of matter and an ‘electrically-charged gas.’ In this state, negatively and positively charged atoms are separated. Scientists believe that as much as 99% of the Universe is made up of plasma, even though it is rarely found on Earth.
To replicate the fusion process, gases need to be heated to over 30 million degrees Celsius. This will completely ionize all atoms. The easiest reaction to duplicate occurs between two hydrogen isotopes: deuterium and tritium. When these two elements fuse they form a helium nucleus, a neutron and a significant amount of energy.
Devices have already been constructed that are capable of producing these extremely high temperatures. A ‘cage’ is created by strong magnetic fields, in the device, that minimizes thermal loss and allows the plasma to be confined long enough for fusion to occur. The tokamak, a donut shaped magnetic chamber, is presently the most advanced of these. Scientists have used it to create temperatures ten times higher than the center of the sun, producing megawatts of power for a few seconds.
Earl Marmar, the head of MIT’s Alcator C-Mod tokamak fusion project, has projected the use of nuclear fusion as a power source by the 2030s. The scientific community are already familiar with how the fusion creation process works, and how to replicate it. There still needs to be extensive research conducted in how to sustain the nuclear fusion once it has been produced, however. Several solutions to this problem are currently being researched including: decreasing the size of the donut hole in the tokamak to harness more energy, or increasing the strength of the magnetic field sustaining the plasma.
To meet the 2030s deadline, when the world’s urban population will have risen significantly, this research may need to be accelerated. Marmar believes that this pressure should be viewed positively, as it motivates the team. Climate change, and continue urbanization, mean that the sooner we are able to produce cost-effective, nuclear fusion energy that can be maintained; the sooner we will be able to help the planet heal from the negative effects of current power sources and expand energy provision.