Creating The Equivalent Of An Artificial Sun Is Much Harder. For One, The Sun Is 1.3 Million Times Larger Than The Earth
From artificial suns to limitless energy, the United States, China and Russia are competing for creating sun-like fusion, which promises a better world for some and worse for others. At the heart of our sun is a ceaseless nuclear furnace, where unparalleled heat and the gravitational force caused by its tremendous mass place incredible pressure on its core. This results in indescribable pressure, fusing hydrogen and helium together. The reaction gives off a tremendous amount of energy in the form of light and heat — the two essential components for life on earth.
For the first time in a long time, realising commercial fusion may well be within humanity’s grasp: within the next decade. In spite of the incredible benefits fusion promises, a breakthrough in the field would cause radical upheaval to the world’s fossil fuel energy industry, impacting petroleum-reliant countries the most.
War and peace
Ever since humans mastered the splitting of the atom through fission, sun-like fusion quickly became the holy grail of every nuclear scientist. This pursuit led to the creation of the hydrogen bomb, and while never used in war, it is potentially 1000 times stronger than the atomic bombs dropped on Hiroshima and Nagasaki. Unlike fission which is used by today’s nuclear power plants, fusion doesn’t produce radioactive waste as a byproduct and only requires hydrogen which is readily found in water. Uranium-235, a highly radioactive isotope used in atom-splitting nuclear weapons, takes 703.8 million years to decay by 50 per cent, and a similar amount of time to lose the remaining 25 per cent.
This presents tremendous problems for governments, making it nearly impossible to store it safely. For instance, a United States proposal to deal with radioactive waste suggested it be stored underground in the middle of the Yucca desert. But even if it was stored in lead-lined steel drums, planners realized the waste would still be radioactive long after the drums fell apart hundreds if not thousands of years later. Given the mutations and cancer radiation causes, fusion remains the ideal standard for nuclear energy. Because fusion doesn’t produce greenhouse gases, scientists the world over see it as a clean, limitless source of energy to power the future. Triggering fusion for a fraction of a second is relatively easy though, compared to sustaining the chain reaction indefinitely to power entire cities.
Fusion is incredibly difficult
Even if it occurs in the sun naturally, creating sustainable fusion is hard. On paper, it’s pretty simple. Smash some atoms together, and soak up the energy. But in reality, creating the equivalent of an artificial sun is much harder. For one, the sun is 1.3 million times larger than the Earth. The kind of gravity the sun’s mass yields is impossible on Earth. Second, fusion of hydrogen at the sun’s core happens in a stellar oven that burns at an intense 15 million degrees celsius. For scientists on earth, the challenge isn’t only in creating the pressure and heat necessary to fuse hydrogen, but also in keeping it contained. So they use magnetic fields to keep it suspended.
That’s more challenging than it sounds. Containing turbulent molten plasma at just the right conditions for fusion under high pressure while subject to heat in the millions of degrees celsius requires significant research, experimentation and continuous trial-and-error. The process also requires an incredible amount of energy input. To make fusion a commercial reality, scientists are working hard to realize an energy output that’s higher than its input. That’s a tall order. In fact, because Earth’s gravity is nowhere near that of the suns’, scientists need to turn up the heat to compensate for the lack of pressure which actually ends up using more energy. Instead of a natural sunny 15 million degrees celsius, fusion reactors on earth need to work at several hundred million degrees celsius. With higher temperatures comes the need for stronger magnetic containment however, requiring even more energy to realize fusion.
But the way scientists work and improve reactors is changing with the introduction of artificial intelligence for data analysis. Physics experiments aren’t simple, and figuring out what data means, or what went wrong takes a significant amount of time. Neural networks tasked with learning the most efficient conditions for fusion make lightning-fast inferences, turn around experiments faster, and feature a rapid learning curve that’s making the entire process much faster. The brunt of the work has already been carried out by physicists and engineers. From 1950 to 2000, levels of reactor density, temperature and total run-time have increased by a factor of one million. Scientists estimate we only need an increase in this ‘triple product’ by a factor of two to break even and produce more energy than reactors require.
Race for power
This means the race is heating up like never before, and it’s primarily between the United States, China and Russia. For some nations, it’s a matter of national security; leaving fusion technology a closely guarded secret. The US team, led by Commonwealth Fusion Systems, a spin-off of the Massachusetts Institute for Technology, plans to show a “net energy gain” by 2025.
China, a more recent addition to the fusion race is close behind, and takes energy just as seriously, and is already competing with Russia for conventional nuclear energy. On December 4 2020, China turned on it’s “artificial sun” for the first time using a Russian-designed reactor it has been improving for some time. While China is working in collaboration with the International Thermonuclear Experimental Reactor (ITER) and is joined by 35 other countries, the race to produce a commercially viable fusion reactor is still very much an individual one for China. While China has already activated its fusion reactor previously for test runs, ITER aims to turn on its ‘artificial sun’ in 2025, with the aim of achieving ‘net power’ by 2035, nearly 10 years after MIT’s estimated deadline.
Fusion promises to reshape much of our known world, making fossil fuels obsolete, while reducing overall energy costs. For countries whose primary exports are petroleum products or liquid natural gas, fusion is a great disruptor. But that’s not to say fusion will replace fossil fuels outright, given their role in running engines the world over. The possibilities don’t end there. NASA recently announced its relative success in producing fusion on a miniature scale, which it aims to utilize in space travel, and a number of companies such as Princeton Satellite Systems, Helicity Space and Pulsar Fusion are working on using fusion to produce new forms of propulsion. As the global race to make fusion a reality nears the finish line, corporate interests are beginning to pay serious attention to its prospects.
Andrew Holland, Executive Director of the Fusion Industry Association, estimates that more than $1.5 billion has been invested in private fusion energy start-ups. That’s to say nothing of government sponsored efforts. Other key backers of fusion include Jeff Bezos, Peter Thiel and Bill Gates. But a stronger sign of how serious fusion is being taken can be seen by the resources poured into it by strategic investors such as Legal & General and traditionally-fossil fuel energy companies like Equinor, Eni and Chevron. For our generation, fusion is poised to introduce a new chapter in humanity’s quest for energy.
This news was originally published at TRT World