It’s long so I’m posting only a small excerpt.~ctm
Long considered a joke, or a pipe dream, fusion is suddenly making enormous leaps
The idea first lit up Dennis Whyte when he was in high school, in the remote reaches of Saskatchewan, Canada, in the 1980s. He wrote a term paper on how scientists were trying to harness fusion (the physical effect that fuels the stars) in wondrously efficient power plants on Earth. This is the ultimate clean-energy dream. It would provide massive amounts of clean electricity, with no greenhouse gases or air pollution. It would do it on a constant basis, unlike solar and wind. Whatever waste it created would be easily manageable, unlike today’s nuclear power plants. And fuel would be limitless. One of the main ingredients needed for fusion is abundant in water. Just one little gram of hydrogen fuel for a fusion reactor would provide as much power as 10 tons of coal.
Whyte got an A on that paper, but his physics teacher also wrote: “It’s too complicated.” That comment, Whyte says with a hearty laugh, “was sort of a harbinger of things to come.”
Indeed, over the next few decades, as Whyte mastered the finicky physics that fusion power would require and became a professor at MIT, the concept seemingly got no closer to becoming reality. It’s not that the science was shaky: It’s that reliably bottling up miniature stars, inside complex machines on Earth, demands otherworldly amounts of patience, not to mention billions and billions of dollars. Researchers, like Whyte, knew all too well the sardonic joke about their work: fusion is the energy source of the future, and it always will be.
That line took on an especially bitter edge one day in 2012, when the U.S. Department of Energy announced it would eliminate funding for MIT’s experimental fusion reactor. Whyte was angry about the suddenness of the news. “It was absolutely absurd — you can put that in your article — fucking absurd that happened with a program that was acknowledged to be excellent.” But above all, he was dismayed. Global warming was bearing down year after year, yet this idea that could save civilization was losing what little momentum it had.
Wendelstein 7-X fusion reactor in Germany, 2017. Photo: Picture Alliance/Getty
So Whyte thought about giving up. He looked for other things to focus on, “stuff that wasn’t as exciting, quite frankly,” but stuff that would be achievable. “Everyone understands delays in projects, and science hurdles you’ve got to overcome, but I saw fusion energy being used for something accelerating away from us,” he says. “You start getting pretty dejected when you realize, in your professional career, you’re never going to see this happen.”
As it turned out, Whyte never really walked away. Instead, he and his colleagues and graduate students at MIT’s Plasma Science and Fusion Center figured out a new angle. And last winter, MIT declared that Whyte’s lab had a fundamentally new approach to fusion and threw its weight behind their plan with an unusually public bet, spinning out a company to capitalize on it. An Italian oil company and private investors — including a firm funded by Bill Gates and Jeff Bezos — put at least $75 million into the company, known as Commonwealth Fusion Systems [CFS]. The startup intends to demonstrate the workings of fusion power by 2025.
The recent progress is remarkable, says the founder of one startup developing fusion power. “The world has been waiting for fusion for a long time.”
Real, live, economically viable power plants could then follow in the 2030s. No joke. When I ask Whyte, who is 54, to compare his level of optimism now to any other point in his career, he says, simply: “It is at the maximum.”
But it’s not just MIT. At least 10 other startups also are trying new approaches to fusion power. All of them contend that it’s no longer a tantalizingly tricky science experiment, and is becoming a matter of engineering. If even just one of these ventures can pull it off, the energy source of the future is closer than it seems.
“It’s remarkable,” says David Kingham, executive vice chairman of Tokamak Energy, a British company whose goal is to put fusion power on the grid by 2030. “The world has been waiting for fusion for a long time.”
Imagine that I told you I was developing a special machine. If I put power into it, I could get 10 times as much out. Because of the undeniable laws of physics, I could show you on paper exactly why it should be a cost-effective source of vast amounts of electricity.
Oh, here’s the catch: My paper sketch would come true — especially the part about it being cost-effective — but only if I built the machine just right. Which might require materials that haven’t been invented yet. Until I perfected that design, my machine would use up more power than it produced. And I couldn’t get close to perfecting the design without spending years and years building expensive test machines that would reveal problems that I would try to address in subsequent versions.
If it seems crazy, well, that’s the story of fusion power.
Fusion definitely works. You see it every day. Our sun and other stars blast hydrogen atoms together with such intense force that their nuclei overcome their normal inclination to repel each other. Instead they fuse, sparking a reaction that transforms the hydrogen into helium and releases cosmic amounts of energy in the process.
We also have great paper sketches for fusion power machines. Fusion happens inside stars because of the crushing pressure created by their gravity. To generate that effect inside a fusion reactor, ionized gas — which is called plasma — must be heated and compressed by man-made forces, such as an ultra-powerful magnetic field. But whatever the method, there’s just one main goal. If you get enough plasma to stay hot enough for long enough, then you can trigger so much fusion inside it that a huge multiplier effect is unlocked. At that point, the energy that is released helps keep the plasma hot, extending the reaction. And there still is plenty of energy left over to turn into electricity.
The problem is that we’re still plugging away on predecessors to the machines that could generate that effect. Ever since the 1950s, scientists have used spherical or doughnut-shaped machines called tokamaks, including the one at MIT that lost funding a few years ago, to create fusion reactions in plasmas bottled up by magnetic fields. But no one has done it long enough — while also getting it hot enough and dense enough — to really tip the balance and get it going. Heating the plasma and squeezing it in place still takes more energy than you can harvest from it.
So, that’s the name of the game in fusion: to get past that point. ITER, a mega-billion-dollar reactor being built in France by an international consortium, is designed to do it and finally prove the concept. But ITER — which is also way behind schedule and over budget — overcomes the limitations of previous tokamaks by being enormous. It’s the size of 60 soccer fields, which probably isn’t an economical setup for power plants that the world will need by the tens of thousands.
ITER (International Thermonuclear Experimental Reactor) under construction. Photo: Christophe Simon/Getty