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A research team has clarified the mechanism behind the generation of runaway electrons during the startup phase of a tokamak fusion reactor. The paper, “Binary Nature of Collisions Facilitates Runaway Electron Generation in Weakly Ionized Plasmas,” was published in the journal Physical Review Letters.

Nuclear energy refers to a power generation method that harnesses the energy of an artificial sun created on Earth, using resources extracted from seawater. To achieve this, technology capable of confining high-temperature plasma exceeding 100 million degrees for extended periods in a fusion is essential.

A tokamak is an artificial sun system in the shape of a torus, with no beginning or end, where magnetic fields are applied to confine particles.

This paper presents a “hybrid” approach to direct drive inertial confinement fusion that can exploit a high-energy gas laser with two opposed beams. The target and driver are asymmetric, much like experiments performed on the National Ignition Facility, but have been designed to benefit from scale and their particular compatibility with a fusion power plant. The imploded masses (and areal densities) are increased by a factor of 12 relative to findings by Abu-Shawareb et al. [Phys. Rev. Lett. 129, 75,001 (2022)] and provide a path to high-gain implosions that robustly ignite. The design also mitigates common concerns such as laser imprint and cross-beam energy transfer. We discuss the rationales for a hybrid target, the methods used to control implosion symmetry, and the implication(s) for inertial fusion energy.

Nuclear microreactors in remote areas require robust monitoring for safe operation.


A team of researchers at the University of Michigan has developed a groundbreaking real-time, 3D temperature mapping system for nuclear microreactors.

This innovation promises to enhance safety monitoring and pave the way for wider adoption of these compact power sources.

The Japanese government is planning to generate some 20 gigawatts of electricity, equivalent to the output of 20 nuclear reactors, through thin and bendable perovskite solar cells in fiscal 2040.

The industry ministry plans to designate next-generation solar cells as the key to expanding renewables…


TOKYO (Kyodo) — The Japanese government is planning to generate some 20 gigawatts of electricity, equivalent to the output of 20 nuclear reactors, through thin and bendable perovskite solar cells in fiscal 2040.

Long before humans began creating nuclear reactors to fulfill our ridiculous energy needs, back when the Earth was dominated by microbes, in fact, nature beat us to it and built the first nuclear reactor on Earth.

In May 1972, a physicist at a nuclear processing plant in Pierrelatte, France, was conducting analysis on uranium samples when he noticed something pretty strange. In usual uranium ore deposits, three different isotopes are found; uranium 238, uranium 234, and uranium 235. Of these, uranium 238 is the most abundant, while uranium 234 is the rarest. Isotope 235 makes up around 0.72 percent of uranium deposits, and is the most coveted, as if you can enrich it past 3 percent it can be used to create a sustained nuclear reaction.

In the samples from the Oklo deposits in Gabon, Africa, isotope 235 was found to make up 0.717 percent of the total. That might not sound like much of a difference, but it’s pretty weird.

In a commercial warehouse overlooking the ocean in New Zealand’s capital Wellington, a startup is trying to recreate the power of a star on Earth using an unconventional “inside out” reactor with a powerful levitating magnet at its core.

Its aim is to produce nuclear fusion, a near-limitless form of clean energy generated by the exact opposite reaction the world’s current nuclear energy is based on — instead of splitting atoms, nuclear fusion sets out to fuse them together, resulting in a powerful burst of energy that can be achieved using the most abundant element in the universe: hydrogen.

Earlier this month, OpenStar Technologies announced it had managed to create superheated plasma at temperatures of around 300,000 degrees Celsius, or 540,000 degrees Fahrenheit — one necessary step on a long path toward producing fusion energy.

Circa 2016


MIT has been developing a small fusion reactor prototype, three of which could power the City of Boston if they were fully built. Though the project lost federal funding for its current fusion device, the school plans to press ahead on building a new, more advanced prototype.

It was a moment three years in the making, based on intensive research and design work: On Sept. 5, for the first time, a large high-temperature superconducting electromagnet was ramped up to a field strength of 20 tesla, the most powerful magnetic field of its kind ever created on Earth.


The next step will be building SPARC, a smaller-scale version of the planned ARC power plant. The successful operation of SPARC will demonstrate that a full-scale commercial fusion power plant is practical, clearing the way for rapid design and construction of that pioneering device can then proceed full speed.

Zuber says that “I now am genuinely optimistic that SPARC can achieve net positive energy, based on the demonstrated performance of the magnets. The next step is to scale up, to build an actual power plant. There are still many challenges ahead, not the least of which is developing a design that allows for reliable, sustained operation. And realizing that the goal here is commercialization, another major challenge will be economic. How do you design these power plants so it will be cost effective to build and deploy them?”

Someday in a hoped-for future, when there may be thousands of fusion plants powering clean electric grids around the world, Zuber says, “I think we’re going to look back and think about how we got there, and I think the demonstration of the magnet technology, for me, is the time when I believed that, wow, we can really do this.”

Physicist Francis Perrin sat at a nuclearfuel-processing plant down in the south of France, thinking to himself: “This cannot be possible.” It was 1972. On the one hand, there was a dark piece of radioactive natural uranium ore, extracted from a mine in Africa. On the other, accepted scientific data about the constant ratio of radioactive uranium in ore.

Examination of this high-grade ore from a mine in Gabon was found to contain a lower proportion of uranium-235 (U-235) — the fissile sort. Only a tiny bit less, but enough to make the researchers sit back and scratch their heads.