My radical plan for small nuclear fission reactors
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0:01 - 0:03Well, I have a big announcement to make today,
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0:03 - 0:05and I'm really excited about this.
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0:05 - 0:07And this may be a little bit of a surprise
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0:07 - 0:11to many of you who know my research
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0:11 - 0:13and what I've done well.
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0:13 - 0:16I've really tried to solve some big problems:
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0:16 - 0:19counterterrorism, nuclear terrorism,
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0:19 - 0:22and health care and diagnosing and treating cancer,
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0:22 - 0:25but I started thinking about all these problems,
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0:25 - 0:29and I realized that the really biggest problem we face,
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0:29 - 0:32what all these other problems come down to,
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0:32 - 0:35is energy, is electricity, the flow of electrons.
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0:35 - 0:38And I decided that I was going to set out
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0:38 - 0:42to try to solve this problem.
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0:42 - 0:46And this probably is not what you're expecting.
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0:46 - 0:47You're probably expecting me to come up here
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0:47 - 0:49and talk about fusion,
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0:49 - 0:51because that's what I've done most of my life.
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0:51 - 0:54But this is actually a talk about, okay --
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0:54 - 0:57(Laughter) —
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0:57 - 1:00but this is actually a talk about fission.
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1:00 - 1:01It's about perfecting something old,
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1:01 - 1:04and bringing something old into the 21st century.
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1:04 - 1:09Let's talk a little bit about how nuclear fission works.
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1:09 - 1:10In a nuclear power plant, you have
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1:10 - 1:13a big pot of water that's under high pressure,
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1:13 - 1:15and you have some fuel rods,
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1:15 - 1:17and these fuel rods are encased in zirconium,
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1:17 - 1:20and they're little pellets of uranium dioxide fuel,
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1:20 - 1:24and a fission reaction is controlled and maintained at a proper level,
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1:24 - 1:27and that reaction heats up water,
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1:27 - 1:30the water turns to steam, steam turns the turbine,
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1:30 - 1:32and you produce electricity from it.
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1:32 - 1:35This is the same way we've been producing electricity,
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1:35 - 1:38the steam turbine idea, for 100 years,
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1:38 - 1:41and nuclear was a really big advancement
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1:41 - 1:43in a way to heat the water,
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1:43 - 1:47but you still boil water and that turns to steam and turns the turbine.
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1:47 - 1:51And I thought, you know, is this the best way to do it?
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1:51 - 1:54Is fission kind of played out,
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1:54 - 1:57or is there something left to innovate here?
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1:57 - 1:59And I realized that I had hit upon something
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1:59 - 2:04that I think has this huge potential to change the world.
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2:04 - 2:07And this is what it is.
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2:07 - 2:10This is a small modular reactor.
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2:10 - 2:14So it's not as big as the reactor you see in the diagram here.
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2:14 - 2:17This is between 50 and 100 megawatts.
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2:17 - 2:18But that's a ton of power.
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2:18 - 2:22That's between, say at an average use,
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2:22 - 2:27that's maybe 25,000 to 100,000 homes could run off that.
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2:27 - 2:30Now the really interesting thing about these reactors
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2:30 - 2:32is they're built in a factory.
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2:32 - 2:34So they're modular reactors that are built
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2:34 - 2:36essentially on an assembly line,
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2:36 - 2:38and they're trucked anywhere in the world,
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2:38 - 2:40you plop them down, and they produce electricity.
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2:40 - 2:44This region right here is the reactor.
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2:44 - 2:46And this is buried below ground, which is really important.
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2:46 - 2:49For someone who's done a lot of counterterrorism work,
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2:49 - 2:52I can't extol to you
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2:52 - 2:54how great having something buried below the ground is
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2:54 - 2:58for proliferation and security concerns.
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2:58 - 3:02And inside this reactor is a molten salt,
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3:02 - 3:05so anybody who's a fan of thorium,
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3:05 - 3:06they're going to be really excited about this,
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3:06 - 3:11because these reactors happen to be really good
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3:11 - 3:14at breeding and burning the thorium fuel cycle,
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3:14 - 3:16uranium-233.
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3:16 - 3:18But I'm not really concerned about the fuel.
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3:18 - 3:22You can run these off -- they're really hungry,
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3:22 - 3:25they really like down-blended weapons pits,
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3:25 - 3:28so that's highly enriched uranium and weapons-grade plutonium
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3:28 - 3:29that's been down-blended.
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3:29 - 3:32It's made into a grade where it's not usable for a nuclear weapon,
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3:32 - 3:35but they love this stuff.
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3:35 - 3:37And we have a lot of it sitting around,
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3:37 - 3:39because this is a big problem.
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3:39 - 3:41You know, in the Cold War, we built up this huge arsenal
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3:41 - 3:43of nuclear weapons, and that was great,
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3:43 - 3:46and we don't need them anymore,
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3:46 - 3:49and what are we doing with all the waste, essentially?
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3:49 - 3:51What are we doing with all the pits of those nuclear weapons?
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3:51 - 3:53Well, we're securing them, and it would be great
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3:53 - 3:55if we could burn them, eat them up,
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3:55 - 3:57and this reactor loves this stuff.
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3:57 - 4:00So it's a molten salt reactor. It has a core,
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4:00 - 4:04and it has a heat exchanger from the hot salt,
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4:04 - 4:08the radioactive salt, to a cold salt which isn't radioactive.
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4:08 - 4:11It's still thermally hot but it's not radioactive.
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4:11 - 4:12And then that's a heat exchanger
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4:12 - 4:16to what makes this design really, really interesting,
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4:16 - 4:19and that's a heat exchanger to a gas.
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4:19 - 4:21So going back to what I was saying before about all power
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4:21 - 4:24being produced -- well, other than photovoltaic --
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4:24 - 4:28being produced by this boiling of steam and turning a turbine,
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4:28 - 4:31that's actually not that efficient, and in fact,
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4:31 - 4:33in a nuclear power plant like this,
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4:33 - 4:38it's only roughly 30 to 35 percent efficient.
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4:38 - 4:40That's how much thermal energy the reactor's putting out
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4:40 - 4:42to how much electricity it's producing.
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4:42 - 4:45And the reason the efficiencies are so low is these reactors
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4:45 - 4:47operate at pretty low temperature.
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4:47 - 4:48They operate anywhere from, you know,
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4:48 - 4:52maybe 200 to 300 degrees Celsius.
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4:52 - 4:56And these reactors run at 600 to 700 degrees Celsius,
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4:56 - 4:59which means the higher the temperature you go to,
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4:59 - 5:02thermodynamics tells you that you will have higher efficiencies.
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5:02 - 5:05And this reactor doesn't use water. It uses gas,
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5:05 - 5:08so supercritical CO2 or helium,
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5:08 - 5:09and that goes into a turbine,
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5:09 - 5:11and this is called the Brayton cycle.
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5:11 - 5:14This is the thermodynamic cycle that produces electricity,
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5:14 - 5:16and this makes this almost 50 percent efficient,
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5:16 - 5:19between 45 and 50 percent efficiency.
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5:19 - 5:21And I'm really excited about this,
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5:21 - 5:23because it's a very compact core.
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5:23 - 5:27Molten salt reactors are very compact by nature,
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5:27 - 5:31but what's also great is you get a lot more electricity out
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5:31 - 5:33for how much uranium you're fissioning,
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5:33 - 5:35not to mention the fact that these burn up.
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5:35 - 5:37Their burn-up is much higher.
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5:37 - 5:39So for a given amount of fuel you put in the reactor,
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5:39 - 5:41a lot more of it's being used.
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5:41 - 5:45And the problem with a traditional nuclear power plant like this
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5:45 - 5:49is, you've got these rods that are clad in zirconium,
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5:49 - 5:52and inside them are uranium dioxide fuel pellets.
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5:52 - 5:54Well, uranium dioxide's a ceramic,
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5:54 - 5:57and ceramic doesn't like releasing what's inside of it.
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5:57 - 5:59So you have what's called the xenon pit,
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5:59 - 6:01and so some of these fission products love neutrons.
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6:01 - 6:03They love the neutrons that are going on
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6:03 - 6:05and helping this reaction take place.
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6:05 - 6:08And they eat them up, which means that, combined with
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6:08 - 6:10the fact that the cladding doesn't last very long,
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6:10 - 6:12you can only run one of these reactors
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6:12 - 6:16for roughly, say, 18 months without refueling it.
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6:16 - 6:21So these reactors run for 30 years without refueling,
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6:21 - 6:24which is, in my opinion, very, very amazing,
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6:24 - 6:26because it means it's a sealed system.
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6:26 - 6:29No refueling means you can seal them up
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6:29 - 6:31and they're not going to be a proliferation risk,
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6:31 - 6:34and they're not going to have
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6:34 - 6:36either nuclear material or radiological material
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6:36 - 6:39proliferated from their cores.
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6:39 - 6:42But let's go back to safety, because everybody
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6:42 - 6:45after Fukushima had to reassess the safety of nuclear,
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6:45 - 6:48and one of the things when I set out to design a power reactor
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6:48 - 6:52was it had to be passively and intrinsically safe,
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6:52 - 6:54and I'm really excited about this reactor
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6:54 - 6:56for essentially two reasons.
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6:56 - 6:59One, it doesn't operate at high pressure.
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6:59 - 7:03So traditional reactors like a pressurized water reactor
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7:03 - 7:05or boiling water reactor, they're very, very hot water
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7:05 - 7:08at very high pressures, and this means, essentially,
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7:08 - 7:11in the event of an accident, if you had any kind of breach
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7:11 - 7:14of this stainless steel pressure vessel,
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7:14 - 7:17the coolant would leave the core.
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7:17 - 7:20These reactors operate at essentially atmospheric pressure,
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7:20 - 7:23so there's no inclination for the fission products
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7:23 - 7:26to leave the reactor in the event of an accident.
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7:26 - 7:28Also, they operate at high temperatures,
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7:28 - 7:31and the fuel is molten, so they can't melt down,
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7:31 - 7:36but in the event that the reactor ever went out of tolerances,
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7:36 - 7:38or you lost off-site power in the case
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7:38 - 7:41of something like Fukushima, there's a dump tank.
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7:41 - 7:46Because your fuel is liquid, and it's combined with your coolant,
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7:46 - 7:48you could actually just drain the core
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7:48 - 7:50into what's called a sub-critical setting,
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7:50 - 7:52basically a tank underneath the reactor
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7:52 - 7:54that has some neutrons absorbers.
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7:54 - 7:58And this is really important, because the reaction stops.
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7:58 - 8:01In this kind of reactor, you can't do that.
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8:01 - 8:04The fuel, like I said, is ceramic inside zirconium fuel rods,
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8:04 - 8:07and in the event of an accident in one of these type of reactors,
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8:07 - 8:09Fukushima and Three Mile Island --
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8:09 - 8:12looking back at Three Mile Island, we didn't really see this for a while —
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8:12 - 8:16but these zirconium claddings on these fuel rods,
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8:16 - 8:19what happens is, when they see high pressure water,
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8:19 - 8:21steam, in an oxidizing environment,
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8:21 - 8:23they'll actually produce hydrogen,
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8:23 - 8:26and that hydrogen has this explosive capability
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8:26 - 8:28to release fission products.
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8:28 - 8:31So the core of this reactor, since it's not under pressure
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8:31 - 8:33and it doesn't have this chemical reactivity,
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8:33 - 8:36means that there's no inclination for the fission products
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8:36 - 8:38to leave this reactor.
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8:38 - 8:40So even in the event of an accident,
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8:40 - 8:44yeah, the reactor may be toast, which is, you know,
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8:44 - 8:46sorry for the power company,
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8:46 - 8:48but we're not going to contaminate large quantities of land.
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8:48 - 8:52So I really think that in the, say,
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8:52 - 8:5420 years it's going to take us to get fusion
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8:54 - 8:56and make fusion a reality,
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8:56 - 8:59this could be the source of energy
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8:59 - 9:01that provides carbon-free electricity.
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9:01 - 9:03Carbon-free electricity.
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9:03 - 9:06And it's an amazing technology because
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9:06 - 9:09not only does it combat climate change,
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9:09 - 9:11but it's an innovation.
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9:11 - 9:14It's a way to bring power to the developing world,
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9:14 - 9:16because it's produced in a factory and it's cheap.
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9:16 - 9:18You can put them anywhere in the world you want to.
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9:18 - 9:22And maybe something else.
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9:22 - 9:24As a kid, I was obsessed with space.
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9:24 - 9:27Well, I was obsessed with nuclear science too, to a point,
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9:27 - 9:29but before that I was obsessed with space,
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9:29 - 9:31and I was really excited about, you know,
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9:31 - 9:33being an astronaut and designing rockets,
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9:33 - 9:35which was something that was always exciting to me.
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9:35 - 9:39But I think I get to come back to this,
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9:39 - 9:42because imagine having a compact reactor in a rocket
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9:42 - 9:45that produces 50 to 100 megawatts.
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9:45 - 9:48That is the rocket designer's dream.
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9:48 - 9:52That's someone who is designing a habitat on another planet's dream.
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9:52 - 9:54Not only do you have 50 to 100 megawatts
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9:54 - 9:58to power whatever you want to provide propulsion to get you there,
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9:58 - 10:00but you have power once you get there.
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10:00 - 10:03You know, rocket designers who use solar panels
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10:03 - 10:06or fuel cells, I mean a few watts or kilowatts --
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10:06 - 10:08wow, that's a lot of power.
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10:08 - 10:10I mean, now we're talking about 100 megawatts.
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10:10 - 10:11That's a ton of power.
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10:11 - 10:13That could power a Martian community.
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10:13 - 10:15That could power a rocket there.
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10:15 - 10:18And so I hope that
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10:18 - 10:20maybe I'll have an opportunity to kind of explore
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10:20 - 10:25my rocketry passion at the same time that I explore my nuclear passion.
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10:25 - 10:28And people say, "Oh, well, you've launched this thing,
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10:28 - 10:30and it's radioactive, into space, and what about accidents?"
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10:30 - 10:33But we launch plutonium batteries all the time.
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10:33 - 10:35Everybody was really excited about Curiosity,
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10:35 - 10:38and that had this big plutonium battery on board
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10:38 - 10:40that has plutonium-238,
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10:40 - 10:42which actually has a higher specific activity
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10:42 - 10:46than the low-enriched uranium fuel of these molten salt reactors,
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10:46 - 10:50which means that the effects would be negligible,
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10:50 - 10:51because you launch it cold,
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10:51 - 10:55and when it gets into space is where you actually activate this reactor.
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10:55 - 10:56So I'm really excited.
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10:56 - 10:59I think that I've designed this reactor here
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10:59 - 11:03that can be an innovative source of energy,
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11:03 - 11:06provide power for all kinds of neat scientific applications,
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11:06 - 11:09and I'm really prepared to do this.
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11:09 - 11:12I graduated high school in May, and --
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11:12 - 11:16(Laughter) (Applause) —
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11:16 - 11:18I graduated high school in May,
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11:18 - 11:21and I decided that I was going to start up a company
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11:21 - 11:23to commercialize these technologies that I've developed,
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11:23 - 11:26these revolutionary detectors for scanning cargo containers
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11:26 - 11:28and these systems to produce medical isotopes,
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11:28 - 11:32but I want to do this, and I've slowly been building up
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11:32 - 11:34a team of some of the most incredible people
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11:34 - 11:36I've ever had the chance to work with,
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11:36 - 11:39and I'm really prepared to make this a reality.
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11:39 - 11:42And I think, I think, that looking at the technology,
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11:42 - 11:47this will be cheaper than or the same price as natural gas,
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11:47 - 11:49and you don't have to refuel it for 30 years,
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11:49 - 11:52which is an advantage for the developing world.
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11:52 - 11:55And I'll just say one more maybe philosophical thing
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11:55 - 11:57to end with, which is weird for a scientist.
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11:57 - 11:59But I think there's something really poetic
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11:59 - 12:03about using nuclear power to propel us to the stars,
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12:03 - 12:06because the stars are giant fusion reactors.
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12:06 - 12:08They're giant nuclear cauldrons in the sky.
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12:08 - 12:12The energy that I'm able to talk to you today,
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12:12 - 12:14while it was converted to chemical energy in my food,
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12:14 - 12:17originally came from a nuclear reaction,
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12:17 - 12:20and so there's something poetic about, in my opinion,
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12:20 - 12:23perfecting nuclear fission
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12:23 - 12:26and using it as a future source of innovative energy.
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12:26 - 12:28So thank you guys.
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12:28 - 12:33(Applause)
- Title:
- My radical plan for small nuclear fission reactors
- Speaker:
- Taylor Wilson
- Description:
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Taylor Wilson was 14 when he built a nuclear fusion reactor in his parents' garage. Now 19, he returns to the TED stage to present a new take on an old topic: fission. Wilson, who has won backing to create a company to realize his vision, explains why he's so excited about his innovative design for small modular fission reactors -- and why it could be the next big step in solving the global energy crisis.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 12:53
Thu-Huong Ha edited English subtitles for My radical plan for small nuclear fission reactors | ||
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Thu-Huong Ha edited English subtitles for My radical plan for small nuclear fission reactors | ||
Thu-Huong Ha edited English subtitles for My radical plan for small nuclear fission reactors | ||
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Joseph Geni added a translation |