ARI SHAPIRO, HOST:
Energy from nuclear fusion has been a part of science fiction for generations.
(SOUNDBITE OF MONTAGE)
DANIEL DAE KIM: (As Raymond) Doctor, we have a successful fusion reaction.
ROBERT DOWNEY JR: (As Tony Stark) Stark Tower is about to become a beacon of self-sustaining, clean energy.
MARK HAMILL: (As Luke Skywalker) Ready for some power?
BEN BURTT: (As R2D2, beeping).
HAMILL: (As Luke Skywalker) OK.
BRUCE GREENWOOD: (As Christopher Pike) Spock detonated a cold fusion device.
MICHAEL J FOX: (As Marty McFly) What are you doing, doc?
CHRISTOPHER LLOYD: (As Dr. Emmett Brown) I need fuel.
SHAPIRO: Well, yesterday, Secretary of Energy Jennifer Granholm announced that scientists had reached a real-life breakthrough in fusion.
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JENNIFER GRANHOLM: This moves us one significant step closer to the possibility of zero-carbon abundant fusion energy powering our society.
SHAPIRO: Well, how close are we? NPR science correspondent Geoff Brumfiel is here to answer that question. Hey, Geoff.
GEOFF BRUMFIEL, BYLINE: Hi there.
SHAPIRO: I remember, when I was in high school, I heard about fusion as kind of this magic bullet to solve the world's energy problems. That was decades ago. Why has it taken so long to reach this point?
BRUMFIEL: Right. So if you'll let me do a little nuclear physics 101 here, I can explain it.
SHAPIRO: Go for it.
BRUMFIEL: Basically, fusion is the act of sticking two lightweight atoms together. And at their cores, atoms have protons. Protons are positively charged. And so just like the end of a magnet, they'll repel each other. So to push them together takes a lot of energy. It takes heating to hundreds of millions of degrees. And so that creates a situation where, like, you can't do it on earth because it will just melt any box you put it in, so you have to suspended in magnetic fields and - or use lasers. It just gets more and more complicated. And that's really it. There's no one thing, but it's just a really tough problem.
SHAPIRO: Why is it worth the effort to solve this really tough problem? What makes it such a great accomplishment?
BRUMFIEL: Well, what you get out the other end, if you can make it work, is pretty much clean, limitless energy. Fusion...
SHAPIRO: Star power.
BRUMFIEL: Star power.
SHAPIRO: Literal star power.
BRUMFIEL: Literal star power because the sun runs on fusion. So we have another source of nuclear energy, which is conventional nuclear energy, but it creates nuclear waste. It feels kind of dangerous.
SHAPIRO: That's splitting atoms instead of shoving them together, right?
BRUMFIEL: Exactly. Exactly. And the problems there, we know, I think, all too well, and we struggle with them. Fusion is something where the reactors could be shut off much more easily, and they would produce less nuclear waste. So it feels both safer and cleaner.
SHAPIRO: And is this breakthrough that was announced yesterday the achievement of all of these dreams people have had for decades?
BRUMFIEL: Well, yes and no. So let me explain. This was done using a giant laser facility. And basically what they did was they took 192 laser beams, and they crushed a tiny pellet of fusion fuel. And they did indeed get more energy out than the laser beams put in. And that's a huge breakthrough for the field. The problem is that those lasers have to be plugged into the wall.
SHAPIRO: (Laughter).
BRUMFIEL: And so it turns out that the energy that you need to get out of the wall is much, much higher. So they, in fact, got probably a little under 1% of the energy overall that they had to put into the entire system.
SHAPIRO: But it is one significant step forward, according to the energy secretary. So what's the next step and the step after that? What does the path ahead look like?
BRUMFIEL: Well, there are several different approaches to fusion. And they all have their challenges, and they're all struggling. And for the laser thing, you would have to have a much more efficient laser, obviously. You'd have to be able to do it many times a second, which means firing the laser over and over again. You'd have to have better targets. There's, like, just this laundry list of technical and engineering achievements you'd need to get through. And frankly, it's going to take decades.
SHAPIRO: So it's not going to be the solution to climate change that we're looking for if we want to cut emissions in half by the end of the decade, which is the Biden administration's goal. But is there a reason to be hopeful about this?
BRUMFIEL: You know, the thing about it is, fusion is a really tough technical problem. And in some sense, climate change is the same thing. Climate change itself is a very tough problem. There's no silver bullet. You just got to keep working at it. So I think the one thing fusion shows is, when humans work on a tough problem, they can make progress. And that's what I take away from it. There's not always a magic solution. That doesn't mean we can't get stuff done.
SHAPIRO: NPR's Geoff Brumfiel. Thanks for the optimism and the reality check.
BRUMFIEL: Thank you. Transcript provided by NPR, Copyright NPR.
