The race is on to find a viable alternative to fossil fuels, and one of mankind’s greatest hopes is fusion power.
So, what is fusion power in laymen’s terms? The demonstration of fusion power that we are all most familiar with is the hydrogen bomb, which is about 1,000 times more powerful than an “ordinary” atomic bomb. The fusion process is what powers the sun. Basically, fusion involves fusing lighter nuclei into a heavier nucleus, which results in the release of a tremendous amount of power. When imitating that process on earth, scientists use two isotopes of hydrogen – H-2, called deuterium, and H-3, called tritium – and these are fused into helium-4.
The problem scientists have grappled with for the past 50 years is how to control that release of energy. If the energy could be released in a slow and controlled fashion, it could be used to produce an unlimited supply of “clean” electricity that is completely non-damaging to the environment.
Scientists need to overcome three problems to achieve this: temperature, time and containment.
For fusion to take place, a tremendous amount of heat is needed to start the reaction. In fact, a heat of about 40,000,000°C (about 72,000,000°F) would need to be achieved – a temperature higher than that of the sun! Then, the plasma that’s created through the heating process needs to be held together at that heat for about one second. And the final problem is that finding a container to hold the plasma that can withstand that heat has thus far proved impossible for scientists.
There is hope, however. Two companies – the British company Tokamak Energy, and the U.S.-based Tri Alpha Energy – both claim to be well on their way to solving these problems.
Tokamak claims it will begin operating its fusion reactor, which is much smaller than other nuclear reactors, in the next few months. They hope to build their first commercial prototype by 2025. Tokamak’s cutting-edge technology utilizes a spherical tokamak which is different to the tokamaks used by other energy companies. A tokamak is a containment device that uses a powerful magnetic field to hold the plasma that has been created by the heat, and Tokamak Energy claims that the device they are working on, the ST40, uses the magnetic field to heat plasma to 15 million°C hotter than the sun; the device will have heating capabilities of 100 million°C. The company’s ambitious aim is to deliver electricity to the grid by 2030.
Tokamak’s main rival, Tri Alpha Energy, is not going to be content with second place. They claim to have developed a machine that can hold hot plasma steady at 10 million°C for over 11 milliseconds. Tri Alpha has been given $500 million to further its research and create a commercially operational fusion reactor by 2027. The company claims that its success lies in an unusual reactor design: a long tube that collides pairs of plasma donuts to produce heat. Beams of high-energy particles are then used to stabilize the power that is produced.
“Until you learn to control and tame [the hot gas], it’s never going to work,” Jaeyoung Park, head of the rival fusion start-up Energy/Matter Conversion Corporation in San Diego told Science Magazine. “In that regard, it’s a big deal. They seem to have found a way to tame it.”
For now, it is difficult to determine who is leading the race to capture fusion power. It will be interesting to see which company finally wins – or if, indeed, either one is eventually successfully able to reproduce and control the magnificent power of the sun.