As long as science fiction writers have been imagining it, scientists have been trying to make it a reality. The holy grail of clean energy. The silver bullet solution to global warming. The power of the sun brought down to Earth. That’s right, nuclear fusion.
Nuclear fusion, if and when it becomes a reality, will change the energy industry–and the world–as we know it. It is, essentially, the key to limitless, renewable, and carbon-free energy. And not only is it many times more powerful than nuclear fission (the process of dividing atoms that currently powers nuclear plants) it does not require any radioactive materials, and therefore does not produce any hazardous radioactive nuclear waste. And, with no radiation, there is no risk of the nuclear meltdowns that have become synonymous with nuclear energy thanks to the tragedies at Chernobyl, Fukushima, and Three Mile Island.
In the south of France, 35 nations are collaborating under the banner of the ITER project, building the world’s largest tokamak, a space-age looking device that employs ultra-powerful magnets to create and manipulate hot plasma into a torus (for the laymen among us, a donut) shape in order to achieve nuclear fusion. ITER’s magnetic field coils are the “most powerful superconductive magnets ever designed” according to Forbes, and the tokamak in southern France will employ 18 of them, weighing in at a whopping 6,000 metric tons. These 35 nations have been toiling away on this project for 35 years–and they’re getting close to a breakthrough. The tokamak functions by merging hydrogen atoms, as occurs naturally on the sun, to form helium atoms, producing incredible amounts of energy, which the tokamak harnesses in the form of heat, which in turn creates steam, which spins a turbine, which creates energy that we can use to power our homes, our industries, and, indeed, our world.
ITER aims to bring its massive tokamak online and achieve “first plasma” in just five years. Last year, when ITER first announced its 2025 first plasma projection, the consortium had just reached a major milestone with the installation of the cryostat base and lower cylinder, bringing the project to 65 percent completion. “Manufactured by India, the ITER cryostat is 16,000 cubic meters,” ITER officials said in a release. “Its diameter and height are both almost 30 meters and it weighs 3,850 tons. Because of its bulk, it is being fabricated in four main sections: the base, lower cylinder, upper cylinder, and top lid.”
Now, in 2020, it’s all about magnets. “The plasma volume inside the tokamak at ITER will be several times larger than that generated by any previous fusion reactors. Because of the high temperatures, metal cannot be used to confine the highly unstable plasma,” explains Forbes. “Therefore, an enormous magnetic field is used to contain the plasma and ensure the fusion reactions can happen. This is achieved by a series of toroidal superconducting magnets, or field coils.”
The magnets that are our greatest hope for achieving commercial nuclear fusion are the size of five- and six-story buildings, each weighing in at 310 metric tons, with a width of nine meters (29 feet) and a towering height of 16.5 meters (54 feet). Japan’s Mitsubishi Heavy Industries (MHI) Group delivered the first installment of what will be 18 massive magnets to ITER in January of this year, “seven and a half years after they were commissioned.”
If commercial fusion becomes within reach when ITER goes online in 2025, the ramifications are impossible to overstate. We could conceivably keep average global temperatures from increasing more than 1.5 degrees Celsius this century while still keeping up with energy demand. We could stop catastrophic climate change in its tracks, and change global geopolitics forever, thereby resolving countless conflicts, as dirty and finite fossil fuels become obsolete. Some of the greatest problems of our time will be solved thanks to the tireless work of scientists, human imagination and ambition, and some really, really big magnets.