China’s ‘Artificial Sun’ Just Broke a Major World Record For Plasma Fusion

Just seven months after it announced a milestone record for plasma fusion, the Chinese Academy of Sciences has absolutely smashed it. Their ‘artificial Sun tokomak reactor has maintained a roiling loop of plasma superheated to 120 million degrees Celsius (216 million degrees Fahrenheit) for a gobsmacking 1,056 seconds, the Institute of Plasma Physics reports. This also beats the previous record for plasma confinement of 390 seconds, set by the Tore Supra tokamak in France in 2003.

This breakthrough by the EAST (Experimental Advanced Superconducting Tokamak, or HT-7U) reactor is a significant advance for fusion experimentation in the pursuit of fusion energy. Succeeding in the generation of usable amounts of energy via nuclear fusion would change the world, but it’s incredibly challenging to accomplish. It involves replicating the processes that take place in the heart of a star, where high pressure and temperature squeeze atomic nuclei together so tightly that they fuse to form new elements. In the case of main sequence stars, these nuclei are hydrogen, which fuse to form helium. Since one helium nucleus is less massive than the four hydrogen nuclei that fuse to make it, the excess mass is radiated as heat and light. This generates a tremendous amount of energy – enough to power a star – and scientists are striving to harness the same process here on Earth. Obviously, there’s a significant challenge in creating the heat and pressure that we find in the heart of a star, and there are different technologies to address them.
In a tokamak, plasma is superheated, and confined in the shape of a torus, or donut, by powerful magnetic fields. But maintaining that confined, superheated plasma for longer time frames in order to cultivate longer reaction times is another problem, since superheated plasmas are chaotic and turbulent, prone to instabilities, resulting in leakage. EAST previously reported a temperature record of 160 million degrees Celsius (288 million degrees Fahrenheit), sustained for 20 seconds (the Sun’s core, for context, is 15 million degrees Celsius; the extra heat in a tokamak makes up for the lower pressure).
On 30 December 2021 – just squeaking in for its goal of achieving 1,000 seconds in 2021 – EAST broke the time record, too. Make no mistake, fusion still has a very long way to go. At the moment, far more energy goes into a fusion generator than we can get out of it; but lengthening the time of plasma confinement is a really important step forward in making self-sustaining plasma fusion a reality.

Source: https://www.sciencealert.com/

Nuclear Fusion Is Now a Question of “If”, Not “When”

A small railway town in southern England could go down in history as the place where nuclear fusion kicked off. The reaction process – which would generate vast amounts of low-carbon energy – has evaded scientists for decades, but a private company in Didcot, Oxfordshire says it’s now a question of if, not when.

Tokamak Energy is firing its nuclear reactor up to 50 million degrees celsius – almost twice the core temperature of the sun. By shooting 140,000 amps of electricity into a cloud of hydrogen gas, the team are trying to force hydrogen atoms to fuse, thereby creating helium. These fusion forces are the same ones that power the sun. While there’s no danger that Didcot could become the new centre of the solar system, the industrial estate could spark the start of a cheap, clean energy supply.

We will crack it,” CEO Chris Kelsall told the BBC on a recent trip, “the answer is out there right now with Mother Nature as we speak. What we have to do is find that key and unlock the safe to that solution. It will be found.”

Having ramped the temperature up to mind-boggling degrees, the experiment’s next step is to see if nuclear fusion can produce more energy than it uses. In case it rings alarm bells to anyone in the vicinity, nuclear fusion is very different from nuclear fission and its associated disasters. The process occurs inside a ‘tokamak’ – a device which uses a powerful magnetic field to contain the swirling cloud of hydrogen gas. This stops the superheated plasma from touching the edge of the vessel, as it would otherwise melt anything it comes into contact with. If anything goes wrong inside a fusion reactor, the device just stops – so there’s no risk of this astronomical heat being unleashed.

The plasma has to be heated to 10 times the temperature of the sun to get it going, and is capable of fusing two hydrogen nuclei into a helium nucleus. Nuclear fission, on the other hand, is the dangerous kind. This creates energy by splitting one ‘heavy’ atom (typically uranium) into two. This breakdown generates a large amount of radioactive waste in the process, which remains hazardous for years. Fusion cannot produce a runaway chain reaction, like the one that happened at Chernobyl in 1986, so no exclusion zone is needed around Milton Park, Didcot, where the reactor is based. Laura Hussey, an editor who works minutes away at a publishing office on the business park, says she is “really encouraged to hear how safe it is and really happy to see this big investment in clean energy.”

Source: https://www.euronews.com/

Limitless, Cheap Clean Energy: China launches Its “Artificial Sun”

China is about to start operation on its “artificial sun“—a nuclear fusion device that produces energy by replicating the reactions that take place at the center of the sun. If successful, the device could edge scientists closer to achieving the ultimate goal of nuclear fusion: near limitless, cheap clean energy.

The device, called HL-2M Tokamak, is part of the nation’s Experimental Advanced Superconducting Tokamak project, which has been running since 2006. In March, an official from the China National Nuclear Corporation announced it would complete building HL-2M by the end of the year.

The coil system was installed in June and since then, work on HL-2M has gone “smoothly,” the Xinhua News Agency reported in November.

Duan Xuru, head of the Southwestern Institute of Physics, which is part of the corporation, announced the device will become operational in 2020 at the 2019 China Fusion Energy Conference, the state news agency said. He told attendees how the new device will achieve temperatures of over 200 million degrees Celsius. That’s about 13 times hotter than the center of the sun. Previous devices developed for the artificial sun experiment reached 100 million degrees Celsius, a breakthrough that was announced in November last year.

Nuclear fusion is the reaction that powers the sun. It involves fusing two lighter atomic nuclei to form a heavier nucleus—a reaction that releases a huge amount of energy. On the sun, where core temperatures reach about 15 million degrees Celsius, hydrogen nuclei combine to form helium.

To recreate this on Earth, scientists must heat the fuel—types of hydrogen—to temperatures over 100 million degrees Celsius. At this point, the fuel becomes a plasma. This extremely hot plasma must be confined and one method scientists have been developing is a donut shaped device called a tokamak. This uses magnetic fields to try to stabilize the plasma so reactions can take place and energy be released. However, plasma is prone to producing bursts. If these touch the reactor wall it can damage the device.

Source: https://www.newsweek.com/