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Home Energy Fusion experiment’s success portends abundant, clean energy in future

Fusion experiment’s success portends abundant, clean energy in future


The possibility of a future of clean, plentiful energy took a big step forward recently when scientists at the Lawrence Livermore National Laboratory in California produced a nuclear fusion reaction resulting in a net energy gain, hailed as a “landmark achievement.”

This is the first time scientists have produced a reaction that generated more energy than it took to achieve the reaction, and could pave the way to limitless, carbon-free energy in a few decades, said University of South Carolina nuclear engineering professor Dr. Ted Besmann. Right now, nuclear fission produces a significant portion of the state’s electricity. Besmann explained the difference between how the nuclei of various atoms are treated in nuclear fission and nuclear fusion.

“In nuclear fission, we take a heavy atom – uranium 235 – and when it breaks apart, it gives off energy. Fusion is at the other end of the spectrum. In fusion we take very, very light elements -hydrogen – and we force the atoms together. And if we provide enough pressure to get them close enough together, they will join together and form a helium atom, and that gives off energy as well. A lot of energy in the form of atoms moving and heat.”

According to Dr. Travis Knight, chairman of the USC Mechanical Engineering department, fusion is much harder to achieve than fission, because the positively-charged hydrogen atoms don’t want to be joined together.

“Like charges repel,” said Knight. “So these positively-charged nuclei, to smash them together, to bring them together, takes enormous amounts of energy and pressure. So it’s those repulsions of those like charges that you’ve got to overcome to bring them together and fuse them to form these more stable nuclei, with a release of energy.”

To produce this fusion of hydrogen nuclei, either lasers are used, as at Livermore (which used 192 lasers to produce the fusion reaction), or giant magnets, the repulsive power of which is stronger than that of the atoms to be fused. Despite the success at Livermore, it’s still a first step, both scientists said. Besmann agreed with Knight that the problem of forcing the fusion of hydrogen has yet to be solved on a large scale.

“The main obstacle to overcome is to get high enough temperatures and pressure – they relate to each other – for long enough, in a large enough space that you get enough atoms to fuse to get enough energy out,” said the professor. “That is the fundamental problem. And so better magnets, better design for magnetic confinement are needed.”

He acknowledged that it won’t be achieved overnight, thus fission reactors will have to continue to be used to produce electricity, probably for several more decades. “Huge, huge engineering and physics issues still confront fusion,” said Besmann. “And we can’t wait for the best answer when we have reasonable answers already for energy. We have to do what we need to do, and spend the money on research and development so that there are these new opportunities in the future.”

These new future opportunities include not only producing a limitless amount of electricity with no radioactive waste (this waste is a chief problem with fission), but eliminating the need to burn carbon-producing fossil fuels such as oil or coal to produce power, and contributing to the advancement of electric vehicles. These actions would prevent huge amounts of carbon dioxide from being released into the atmosphere, an enormous boon to reducing the rate of climate change.

Besmann said numerous companies worldwide are working on producing practical fusion sooner rather than later. “There’s a venture with MIT called Commonwealth Fusion, and they think they will have something commercial in 10, 15 years perhaps. Or at least a demonstration. I find that remarkable. I hope they’re right.  And there are other similar concepts being pursued elsewhere around the world.”

“It’s interesting, this thing what start up companies have done,” echoed Knight. “So over time, I think we can expect those lessons to be learned and march ever forward. And beyond that is still the engineering part of how to make electricity from it. Which is an engineering problem, it’s certainly doable.”

Realistically, Knight said, despite fusion’s being an abundant and cleaner power, fission will still be around until fusion is developed enough to replace it.

“Fission’s gonna be around for a long time, a fission reactor is a big investment,” he said. “So if you build it, you’re building something that’s gonna be there for 60 years, 80 years, maybe even longer.

“Even if fusion came to the fore and was viable and overcame all the engineering problems that would accompany it, those reactors are gonna be here for a long time. My prediction is to the end of the century.”

The good news, Besmann added, is that “long term research always pays off. And just as we plant trees for our future generations, this is a technological tree we’re planting, so that folks in the future will have an opportunity to use energy more wisely and in a more environmentally compatible way.”

He said that in order to be successful, society has to invest in the future, and this kind of research is that kind of investment. “It’s maybe not something that we’re gonna see tomorrow or the day after, but in the end we benefit enormously as we learn from the discoveries of the past.”

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