4. Hotter Than The Sun | Cami Collins
December 6, 2017 6 a.m.
Cami Collins was a small town girl with a dream to be a physicist. Now, she handles particles ten times hotter than the sun! Her goal is to create a new energy source for future generations.
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Margot: San Diego is one of the largest scientific research hubs in the country. So, who are the intrepid scientists in search of discovery, pushing the frontiers of human knowledge? This is Rad Scientist, where the scientist becomes the subject. I'm your host, Margot Wohl. Today’s Rad Scientist is Cami Collins. She’s a physicist focused on one big question: can we develop a new energy source for future generations?
Cami: In the long run, we're not going to have fossil fuels. In 100, 150 years, they're going to be running out. And we have to come up with something.
Margot: That something is in the works at General Atomics in San Diego, where Cami’s been a scientist for the past three years. General Atomics is a defense contractor for the US government that makes all sorts of high tech things -- like drones, lasers, magnetic levitation devices. But Cami works on one of their most ambitious projects, figuring out how to use nuclear fusion to make electricity.
Cami: We have this dream of using fusion for an energy source one day. This is the same process that happens in the sun. This produces a lot of energy, so we want to make that happen on Earth.
Margot: You’re probably thinking, don’t we already have nuclear power plants? We do, but these plants use nuclear fission, which is different from nuclear fusion in a lot of ways.
Cami: Nuclear fission is this process where you split atoms and you produce a lot of nuclear waste, high level nuclear waste. Fusion is not like that. Fusion is the process, where basically two hydrogen atoms come together and they fuse, and they produce helium.
Margot: Okay, so nuclear fission, the process we use now, splits atoms apart. Fusion, what Cami studies, fuses atoms together. Hydrogen atoms, actually. That means the fuel for this energy is all around us, in one the world’s most abundant resources: H2O.
And there’s one more big difference. Fusion produces a fraction of the nuclear waste compared to fission. Plus there’s no risk of a reactor meltdown, like Fukushima or Chernobyl. And unlike a lot of the energy sources we use today…
Cami: Fusion does not produce any greenhouse gases. Fusion produces helium, so we love helium. That's fine.
Margot: Yea, I love Helium! But there’s more to love. You know how I said the fuel for this energy can come from water? Well, you wouldn’t need a lot of water to get some major power. With just one gallon...
Cami: You would have enough power to power your home for your entire lifetime. If you could produce ungodly amounts of electricity, and it's cheap, then you can do anything with that. Free electricity for all.
Margot: That would be rad!So now you might think it is less crazy that at ten years old, Cami decided that she would be a nuclear physicist.
Cami: I remember very specifically we were reading our science books. I was reading ahead because we were in this section about alternative energy. They talked about nuclear fission, and then they talked about fusion, about you can join atoms and it doesn't produce nuclear waste. I was like, "Wow. That's a really bright, great idea."
Cami: I couldn't imagine doing anything else. Maybe if I opened up like a dog resort with puppies and stuff, but other than that, nothing else is appealing.
Margot: Cami grew up in Glasgow, Montana , population 3500.
Cami: I think being brought up in that environment, like I learned how to weld. I built a hovercraft with my dad. It's a big chunk of wood with a lawnmower engine and some styrofoam underneath.
It worked. The thing lifted. So I step on this thing. It was really unstable. It's wobbling back and forth. Then all of a sudden, the styrofoam caught on the cement, went into the car fan on the lawnmower. It just like snow everywhere. The whole thing just got destroyed. That was like, "Aw, I guess this is not going to be my vehicle to driving to high school."
Margot: Yea, Back to the Future left a lot of us with unfulfilled hoverboard dreams. But most of us never tried to build one! The tinkering skills she learned in the process came in handy.
Cami: These building skills, when I got to grad school were invaluable. I was so lucky by the time I got to grad school, I walked into this room and it was completely empty. I got to build an entire experiment from scratch.
Margot: An experiment about plasma, the stuff of stars. The stuff that’s needed for nuclear fusion.
Cami: Plasma is actually, it's the fourth state of matter. There's solid, liquid, gas, and if you heat a gas, then you make a plasma. Plasma is made up of charged particles, like electrons and positively charged ions. They're all just bouncing around.
Margot: And every once in a while...
Cami. Two positively charged ions come together and join.
Margot: In the process they release a boatload of energy. That’s nuclear fusion. And it needs the right conditions to happen because normally…
Cami: Two positive charges repel. They don't want to go together. So, you have to have these particles hot enough so that they're moving fast enough in order to join together. Then, you also have to have enough ions coming together and fusing to actually make a efficient fusion reactor. Then, the last thing is that you need to be able to confine the ions long enough in order to make collisions.
Margot: Ok so hot enough, dense enough, confined for a long time. So..just put it on the new york subway? [joke drum sound] No but really, why not just trap it in a container?
Cami: It's tricky because you have to make sure that this really, really hot plasma, which is actually like 10 times hotter than the surface of the sun, it has to be contained in a way that it doesn't touch the walls and melt your container.
Margot: 10 times hotter than the sun? Yea we don’t really have materials that can stand up to 180 million degrees Fahrenheit.
Cami: But the cool thing is that we have charged particles. They will follow magnetic field lines. We can use magnetic field lines to steer where the plasma goes. Actually, that's one of the things that I study, is how to confine the most energetic particles
Margot: So you’re like the police officer for those hot ions?
Cami: Yeah. They got to stay in there. Don't come out.
Margot: Cami and her colleagues contain these hot particles inside a device shaped like a toroid - which just looks like a donut. It’s called a tokamak.
Margot: I really want to see the real thing, so Cami takes me to what she calls “The Pit,” where it lives.
Cami: The pit, we should go. This is the chance, opportunity of a lifetime. You're going to get to see the entire tokamak.
Margot: Let's do it.
Cami: Yeah, let's do it. Okay. The first thing that we have to do is get some helmets.
Margot: Helmets, check.
Cami: We're going to go in. It's going to be a little bit loud. We're going to first enter through these really big doors. When we're actually firing a plasma, these big doors are shut. We're just seeing the top half of the donut. There's an entire floor below us. That little opening down there is usually where we enter the vessel during our calibration stuff. It's a man-sized hole, so you can slide right in, although, I don't think I can slide in because ... I’m pregnant.
Margot: Did you catch that? She said she’s pregnant. So it might be hard for her to fit into the tokamak for a bit.
Cami: There are certain fueling systems. This is called a pellet injector and injects little, tiny frozen pellets of fuel into the plasma. It's like basically shooting it in with a gun. Lots of pipes. Lots of tubes.
Margot: Seriously, it looks like an improvised lego project that was made by twenty different builders.
Cami: I think the map is really much of it is in people's heads. Not one person knows everything. I can tell you that.
Margot: It’s definitely a team effort at this facility. Just down the hall, most of the crew sit at rows of desks facing a giant screen -- sort of like those pictures you see of NASA headquarters.
Cami: So, this is the control room. We have many different scientists from many, many different institutions. I think there are probably about 100 scientist engineers that work here.
Margot: One of those people is a chief operator. He presses the buttons fire up the tokomak and make a plasma.
Chief Operator: All right we're ready. Please clear the annex. We're starting the sequence for the next test shot. Ready to fire shot number six. Five one in 20 seconds.
Margot: Remember, to get a plasma they need to make a vacuum in the donut, shoot in some hydrogen, make it really really hot, and turn on the magnetic field.
Chief Operator: Three seconds. Two. One. Now. Shot in progress. Shot complete.
Cami: That's it. Yup. It's just a short amount of time, but you still get an incredible amount of data from ... People have been analyzing a single shot for years.
Margot: The “shot” is a way to test new conditions to figure out which makes the ideal reaction. Each scientist gets a chance to be the session leader. When you are a session leader you get to use the tokamak to conduct your experiments. And one more thing...
Cami: Your job, most important, is to bring to donuts in the morning for everybody to consume and get energized with.
Margot: Donuts because of the toroid shape?
Cami: Yeah, of course.
Margot: That's like a fuel that burns out very quickly.
Cami: Yeah. That's right. The energy in the donut is far more energy than we produce in our fusion plasmas, unfortunately.
Margot: Wait, really? More energy in a donut than the plasma?
Cami: So far, we have not demonstrated that you can get more power out of the fusion plasma than you put in.
Margot: I mean, they do have to heat the plasma to insane temperatures. That takes a lot of energy. And right now, they haven’t made the fusion reaction efficient enough to have a net gain of energy. That’s why Cami and her colleagues need to keep doing research.
Cami: We are in the very early stages of just still trying to develop and show that it's feasible.
Margot: People have actually been trying to make nuclear fusion a reality for the past 50 years. So why don’t we have free electricity for all yet?
Cami: Yes I know. But, it's because it's hard. This is harder than putting man on the moon and it's also underfunded because it's a long time scale. When you tell a politician, "Hey, we're working on something so that we'll get a reactor going in 40 years from now," they're not interested in funding that because it's not in their career. It's not within their time span.
Margot: It seems amazing to me that a scientist might work on a problem their entire lives without solving it. But if fusion isn’t a feasible source of energy in Cami’s lifetime, then maybe it will be for the next generation.
Cami: First born coming up October this year. All I can think about is the upcoming life events. We're moving into a new house and having a baby within like two weeks. It's like everything has to happen at once. I think Einstein said, "Time is what keeps everything from happening at once," and time is not on my side right now.
Margot: I guess you could say the same about nuclear fusion research.
That’s it for this episode of Rad Scientist. But before we go it’s time for the Moment of Xenopus where we delve into a hobby of Cami’s that, surprise, involves plasma. An introduction to whistler waves.
Cami: This is kind of wild. So, whistler waves are very low frequency radio waves that propagate in the earth’s magnetosphere. They’re triggered by lightning and you can actually hear them in the middle of the desert with the right electronics.
Because of the way they travel, they sound like downward chirping. So, it’s like choooooo. [whistler wave sounds]
They’re really cool.
Margot: But don’t just take her word for it! If you want to listen to whistler waves like Cami, you can build your own receiving device. Just look up the NASA Inspire Project.
Margot: This podcast is supported by the KPBS Explore Project, bringing local content to the radio. This episode was produced by me, Margot Wohl. Grant Fisher is our audio mix master and theme song composer. Shahla Farzan is script editor. Logo by Kyle Fisher. At KPBS, Emily Jankowski is technical director, Melanie Drogseth is program coordinator, Jill Linder is programming manager, Nate John is innovation specialist, and John Decker is director of programming. Additional music was by The Losers, Macaw, Johnny Ripper, Podington Bear, Role Music and Level Clearer. Subscribe to the podcast if you can and leave a review. Until next episode, stay rad.