Posts Tagged ‘nuclear power plant’
Small nuclear fission reactors? How small, how radical?
Well, I have a big announcement to make today, and I’m really excited about this. And this may be a little bit of a surprise to many of you who know my research and what I’ve done well.
I’ve really tried to solve some big problems: counterterrorism, nuclear terrorism, and health care and diagnosing and treating cancer, but I started thinking about all these problems, and I realized that the really biggest problem we face, what all these other problems come down to, is energy, is electricity, the flow of electrons. (Need a huge explanation)
And I decided that I was going to set out to try to solve this problem.
And this probably is not what you’re expecting. You’re probably expecting me to come up here and talk about fusion, because that’s what I’ve done most of my life.
But this is actually a talk about fission.
It’s about perfecting something old, and bringing something old into the 21st century.
Let’s talk a little bit about how nuclear fission works. In a nuclear power plant, you have a big pot of water that’s under high pressure, and you have some fuel rods, and these fuel rods are encased in zirconium, and they’re little pellets of uranium dioxide fuel, and a fission reaction is controlled and maintained at a proper level, and that reaction heats up water, the water turns to steam, steam turns the turbine, and you produce electricity from it.
This is the same way we’ve been producing electricity, the steam turbine idea, for 100 years, and nuclear was a really big advancement in a way to heat the water, but you still boil water and that turns to steam and turns the turbine.
And I thought, you know, is this the best way to do it?
Is fission kind of played out, or is there something left to innovate here?
And I realized that I had hit upon something that I think has this huge potential to change the world. And this is what it is.
This is a small modular reactor. So it’s not as big as the reactor you see in the diagram here.
This is between 50 and 100 megawatts. But that’s a ton of power. About 25,000 to 100,000 homes could run off that power.
Now the really interesting thing about these reactors is they’re built in a factory. (Are the other reactors built onsite?)
So they’re modular reactors that are built essentially on an assembly line, and they’re trucked anywhere in the world, you plop them down, and they produce electricity. This region right here is the reactor.
And this is buried below ground, which is really important. (The other reactors are not buried the same way?)
For someone who’s done a lot of counterterrorism work, I can’t extol to you how great having something buried below the ground is for proliferation and security concerns.
3:09 And inside this reactor is a molten salt, so anybody who’s a fan of thorium, they’re going to be really excited about this, because these reactors happen to be really good at breeding and burning the thorium fuel cycle, uranium-233.
But I’m not really concerned about the fuel.
You can run these off — they’re really hungry, they really like down-blended weapons pits, so that’s highly enriched uranium and weapons-grade plutonium that’s been down-blended.
It’s made into a grade where it’s not usable for a nuclear weapon, but they love this stuff.
And we have a lot of it sitting around, because this is a big problem.
You know, in the Cold War, we built up this huge arsenal of nuclear weapons, and that was great, and we don’t need them anymore, and what are we doing with all the waste, essentially?
What are we doing with all the pits of those nuclear weapons? Well, we’re securing them, and it would be great if we could burn them, eat them up, and this reactor loves this stuff.
So it’s a molten salt reactor. It has a core, and it has a heat exchanger from the hot salt, the radioactive salt, to a cold salt which isn’t radioactive.
It’s still thermally hot but it’s not radioactive.
And then that’s a heat exchanger to what makes this design really interesting, and that’s a heat exchanger to a gas.
So going back to what I was saying before about all power being produced — well, other than photovoltaic — being produced by this boiling of steam and turning a turbine, that’s actually not that efficient, and in fact, in a nuclear power plant like this, it’s only roughly 30 to 35 percent efficient.
That’s how much thermal energy the reactor’s putting out to how much electricity it’s producing. And the reason the efficiencies are so low is these reactors operate at pretty low temperature. They operate anywhere from maybe 200 to 300 degrees Celsius.
And these smaller reactors run at 600 to 700 degrees Celsius, which means the higher the temperature you go to, thermodynamics tells you that you will have higher efficiencies. And this reactor doesn’t use water. It uses gas, so supercritical CO2 or helium, and that goes into a turbine, and this is called the Brayton cycle.
This is the thermodynamic cycle that produces electricity, and this makes this almost between 45 and 50 percent efficiency.
And I’m really excited about this, because it’s a very compact core. Molten salt reactors are very compact by nature, but what’s also great is you get a lot more electricity out for how much uranium you’re fissioning, not to mention the fact that these burn up. Their burn-up is much higher. So for a given amount of fuel you put in the reactor, a lot more of it’s being used.
5:52 And the problem with a traditional nuclear power plant like this is, you’ve got these rods that are clad in zirconium, and inside them are uranium dioxide fuel pellets.
Well, uranium dioxide’s a ceramic, and ceramic doesn’t like releasing what’s inside of it.
So you have what’s called the xenon pit, and so some of these fission products love neutrons. They love the neutrons that are going on and helping this reaction take place. And they eat them up, which means that, combined with the fact that the cladding doesn’t last very long, you can only run one of these reactors for roughly, say, 18 months without refueling it.
So these small reactors run for 30 years without refueling, which is, in my opinion, very, very amazing, because it means it’s a sealed system. No refueling means you can seal them up and they’re not going to be a proliferation risk, and they’re not going to have either nuclear material or radiological material proliferated from their cores.
6:49 But let’s go back to safety, because everybody after Fukushima had to reassess the safety of nuclear, and one of the things when I set out to design a power reactor was it had to be passively and intrinsically safe, and I’m really excited about this reactor for essentially two reasons.
1. One, it doesn’t operate at high pressure. So traditional reactors like a pressurized water reactor or boiling water reactor, they’re very, very hot water at very high pressures, and this means, essentially, in the event of an accident, if you had any kind of breach of this stainless steel pressure vessel, the coolant would leave the core.
These small reactors operate at essentially atmospheric pressure, so there’s no inclination for the fission products to leave the reactor in the event of an accident.
2. Also, they operate at high temperatures, and the fuel is molten, so they can’t melt down, but in the event that the reactor ever went out of tolerances, or you lost off-site power in the case of something like Fukushima, there’s a dump tank.
Because your fuel is liquid, and it’s combined with your coolant, you could actually just drain the core into what’s called a sub-critical setting, basically a tank underneath the reactor that has some neutrons absorbers. And this is really important, because the reaction stops.
In the traditional kind of reactor, you can’t do that. The fuel, like I said, is ceramic inside zirconium fuel rods, and in the event of an accident in one of these type of reactors, Fukushima and Three Mile Island — looking back at Three Mile Island, we didn’t really see this for a while — but these zirconium claddings on these fuel rods, what happens is, when they see high pressure water, steam, in an oxidizing environment, they’ll actually produce hydrogen, and that hydrogen has this explosive capability to release fission products.
The core of this small reactor, since it’s not under pressure and it doesn’t have this chemical reactivity, means that there’s no inclination for the fission products to leave this reactor.
So even in the event of an accident the reactor may be toast, which is, you know, sorry for the power company, but we’re not going to contaminate large quantities of land.
So I really think that in the, say, 20 years it’s going to take us to get fusion and make fusion a reality, this could be the source of energy that provides carbon-free electricity. Carbon-free electricity.
9:14 And it’s an amazing technology because not only does it combat climate change, but it’s an innovation. It’s a way to bring power to the developing world, because it’s produced in a factory and it’s cheap. You can put them anywhere in the world you want to.
And maybe something else. As a kid, I was obsessed with space. Well, I was obsessed with nuclear science too, to a point, but before that I was obsessed with space, and I was really excited about being an astronaut and designing rockets, which was something that was always exciting to me.
But I think I get to come back to this, because imagine having a compact reactor in a rocket that produces 50 to 100 megawatts. That is the rocket designer’s dream.
That’s someone who is designing a habitat on another planet’s dream. Not only do you have 50 to 100 megawatts to power whatever you want to provide propulsion to get you there, but you have power once you get there.
You know, rocket designers who use solar panels or fuel cells, I mean a few watts or kilowatts — wow, that’s a lot of power. I mean, now we’re talking about 100 megawatts. That’s a ton of power. That could power a Martian community. That could power a rocket there. And so I hope that maybe I’ll have an opportunity to kind of explore my rocketry passion at the same time that I explore my nuclear passion.
And people say, “Oh, well, you’ve launched this thing, and it’s radioactive, into space, and what about accidents?”
But we launch plutonium batteries all the time. Everybody was really excited about Curiosity, and that had this big plutonium battery on board that has plutonium-238, which actually has a higher specific activity than the low-enriched uranium fuel of these molten salt reactors, which means that the effects would be negligible, because you launch it cold, and when it gets into space is where you actually activate this reactor.
I’m really excited. I think that I’ve designed this reactor here that can be an innovative source of energy, provide power for all kinds of neat scientific applications, and I’m really prepared to do this.
I graduated high school in May and I decided that I was going to start up a company to commercialize these technologies that I’ve developed, these revolutionary detectors for scanning cargo containers and these systems to produce medical isotopes, but I want to do this, and I’ve slowly been building up a team of some of the most incredible people I’ve ever had the chance to work with, and I’m really prepared to make this a reality.
And I think that looking at the technology, this will be cheaper than or the same price as natural gas, and you don’t have to refuel it for 30 years, which is an advantage for the developing world.
12:02 And I’ll just say one more maybe philosophical thing to end with, which is weird for a scientist. But I think there’s something really poetic about using nuclear power to propel us to the stars, because the stars are giant fusion reactors. They’re giant nuclear cauldrons in the sky.
The energy that I’m able to talk to you today, while it was converted to chemical energy in my food, originally came from a nuclear reaction, and so there’s something poetic about, in my opinion, perfecting nuclear fission and using it as a future source of innovative energy.
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My radical plan for small nuclear fission reactorsTaylor 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.TED · 794 Shares · Mar 6, 2014
U.S. Nuclear Agency: Safety Record How close are you from an earthquake prone region? How close is the nearest nuclear power plant? Do we all need to say a prayer?
A magnitude-6.9 earthquake struck off the coast of Northern California on Sunday night, March 9, 2014, the U.S. Geological Service reported.
The epicenter was 48 miles west-northwest of Ferndale and 50 miles west of Eureka at a depth of 4.3 miles, the USGS said.
The quake, which occurred at 10:18 p.m. PT (1:18 a.m ET), was initially reported as magnitude 6.1, but seismologists revised it upward to 6.9. It was followed by about a half-dozen aftershocks, including one of magnitude 4.6.
In the tense days after a powerful earthquake and tsunami crippled the Fukushima Daiichi power plant in Japan on March 11, 2011, staff at the U.S. Nuclear Regulatory Commission made a concerted effort to play down the risk of earthquakes and tsunamis to America’s aging nuclear plants, according to thousands of internal emails reviewed by NBC News. BILL DEDMAN posted this March 11, 2014
U.S. Nuclear Agency Hid Concerns, Hailed Safety Record as Fukushima Melted
The emails, obtained via the Freedom of Information Act, show that the campaign to reassure the public about America’s nuclear industry came as the agency’s own experts were questioning U.S. safety standards and scrambling to determine whether new rules were needed to ensure that the meltdown occurring at the Japanese plant could not occur here.
At the end of that long first weekend of the crisis 3 years ago, NRC Public Affairs Director Eliot Brenner thanked his staff for sticking to the talking points that the team had been distributing to senior officials and the public.
“While we know more than these say,” Brenner wrote, “we’re sticking to this story for now.”
There are numerous examples in the emails of apparent misdirection or concealment in the initial weeks after the Japanese plant was devastated by a 9.0 earthquake and 50-foot tsunami that knocked out power and cooling systems at the six-reactor plant, eventually causing releases of radioactive material:
- Trying to distance the U.S. agency from the Japanese crisis, an NRC manager told staff to hide from reporters the presence of Japanese engineers in the NRC’s operations center in Maryland.
- If asked whether the Diablo Canyon Power Plant on the California coast could withstand the same size tsunami that had hit Japan, spokespeople were told not to reveal that NRC scientists were still studying that question. As for whether Diablo could survive an earthquake of the same magnitude, “We’re not so sure about, but again we are not talking about that,” said one email.
- When skeptical news articles appeared, the NRC dissuaded news organizations from using the NRC’s own data on earthquake risks at U.S. nuclear plants, including the Indian Point Energy Center near New York City.
- And when asked to help reporters explain what would happen during the worst-case scenario — a nuclear meltdown — the agency declined to address the questions.
As the third anniversary of Fukushima on Tuesday approaches, the emails pull back the curtain on the agency’s efforts to protect the industry it is supposed to regulate.
The NRC officials didn’t lie, but they didn’t always tell the whole truth either. When someone asked about a topic that might reflect negatively on the industry, they changed the subject.
NBC News requested in late March 2011 all of the emails sent and received by certain NRC staffers during the first week of the crisis.
Other news organizations and watchdogs filed similar requests. The NRC has now been posting thousands of emails in its public reading room over the past two years.
NBC NEWSSee details of the 62 U.S. nuclear power plants, along with their age and safety records.
The NRC declined to discuss specific emails or communications.
But Brenner provided an emailed statement: “The NRC Office of Public Affairs strives to be as open and transparent as possible, providing the public accurate information in the proper context. We take our communication mission seriously. We did then and we do now. The frustration displayed in the chosen e-mails reflects more on the extreme stress our team was under at the time to assure accuracy in a context in which information from Japan was scarce to nonexistent. These e-mails fall well short of an accurate picture of our communications with the American public immediately after the event and during the past three years.”
Dating back to the Three Mile Island nuclear crisis in 1979, many nuclear watchdogs and critics have said that the NRC acts first to protect the industry, and its own reputation. One critic said these emails solidify that perception.
“The NRC knew a lot more about what was going on than it wanted to tell the American people,” said Edwin Lyman, senior scientist at the nuclear watchdog group Union of Concerned Scientists and co-author of the new book “Fukushima: The Story of a Nuclear Disaster,” which relied on some of the same emails.
“They immediately put out information that implied that U.S. reactors were in a better position to withstand Fukushima type events than Fukushima reactors were, but it was clear that the what the NRC knew internally was not nearly as positive.”
‘We all need to say a prayer’
From the earliest hours of the crisis, the emails among NRC staff show deep concern about the developing crisis in Japan, particularly among the technical experts.
The first word that the powerful earthquake and tsunami waves had devastated the Fukushima plant came early morning (Eastern time) on March 11, 2011.
Throughout the day, staff at NRC headquarters in Rockville, Md., struggled to learn what was going on in Japan. The chief of the NRC Component Integrity Branch, senior engineer David Rudland, was asked by a colleague if he had any new information. [The emails excerpted in this article are shown in full in a PDF file.]
From: Brenner, Eliot Date: Friday, March 11, 2011, 1:54:57 PM While one reporter knows or has guessed that there are Japanese here in our Ops center in communication with their home authorities, we will NOT make the[m] available and we will NOT volunteer their presence. If anyone knows they (Japanese scientists) are here and wants to talk with them, they will have to make the request through the embassy to have it relayed to these folks.
The memo also instructed staff to evade any questions about efforts by the NRC’s Office of Nuclear Reactor Regulation (NRR) to model the effects of similar earthquakes and tsunamis on California plants:
“NRR is getting tasked with making an overlay of the Japanese conditions … to see how west coast plants stack up against it,” it said. “We think preliminary Diablo would have had no trouble with a wave that size. [For an earthquake of about] 8.9 we’re not so sure about, but again we are not talking about that.”
NBC NEWSFind the distance from any U.S. location to the nearest nuclear power plants with this map from Esri.
In congressional testimony and interviews in that first week, NRC Chairman Gregory Jaczko was quick to say that the NRC could learn lessons from Fukushima.
“We’re going to take a good solid look at everything that comes out of Japan, and if we need to make modifications to our facilities in this country, then we’ll do that,” he told NBC News on March 16.
Gregory did not disclose that the NRC technical staff had already been reassessing, before Fukushima, increased risks from earthquakes, tsunamis, dam failures and power blackouts.
Jaczko did push for release of a report on Fukushima and its lessons just 90 days after Fukushima. Some of those recommendations have been implemented. Jaczko, who resigned in 2012, declined a request last week to be interviewed.
‘Non-public information’
The talking points written during the emergency for NRC commissioners and other officials were divided into two sections: “public answer” and “additional technical, non-public information.” Often the two parts didn’t quite match.
One topic the NRC avoided in the talking points, even when responding to a direct question: meltdown.
“Q. What happens when/if a plant ‘melts down’?
“Public Answer: In short, nuclear power plants in the United States are designed to be safe. To prevent the release of radioactive material, there are multiple barriers between the radioactive material and the environment, including the fuel cladding, the heavy steel reactor vessel itself and the containment building, usually a heavily reinforced structure of concrete and steel several feet thick.
“Additional, non-technical, non-public information: The melted core may melt through the bottom of the vessel and flow onto the concrete containment floor. The core may melt through the containment liner and release radioactive material to the environment.”
The Japanese public television network, NHK, asked if the NRC could provide a graphic depicting what happens during a meltdown of a nuclear reactor.
From: McIntyre, David Date: Friday, March 18, 2011, 9:02 AM NRC would not have such a graphic. I suspect any number of anti-nuclear power organizations might.
When reporters asked if the Japanese emergency could affect licensing of new reactors in the U.S., the public answer was “It is not appropriate to hypothesize on such a future scenario at this point.”
The non-public information was more direct: This event could potentially call into question the NRC’s seismic requirements, which could require the staff to re-evaluate the staff’s approval of the AP1000 and ESBWR (the newest reactor designs from Westinghouse and General Electric) design and certifications.”
On the subject of tsunamis, the public assurances omitted the “non-public ” nuances that might have given the public reasons to doubt nuclear power safety:
- Design standards varied significantly from plant to plant in the U.S.
- The experience in Japan had taught the NRC that it needed to study the dangerous effects of “drawdown,” the powerful receding of ocean water near the shore that can precede a tsunami’s arrival.
- And although the U.S. was developing new tsunami standards, those wouldn’t be in draft form for another year.
‘It was a hydrogen explosion’
The NRC spokespeople sometimes had trouble following the public debate, because for days their computers were blocked by security rules from accessing Twitter and YouTube. And they often had incomplete information about events in Japan.
From: McIntyre, David Date: Saturday, March 12, 2011, 10:02 PM Just saw an incoherent discussion on cnn by Bill Nye the science guy who apparently knows zilcho about reactors and an idiot weatherman who said Hydrogen explosion? Pfft. I’m not buying it.
His boss sent back the following reply, correcting the staffer and explaining plans to ask the Obama administration to help blunt critical news coverage.
From: Brenner, Eliot Date: Saturday, March 12, 2011, 10:07 PM 1: There is a good chance it was a hydrogen explosion that took the roof off that building, though we are not saying that publicly. 2: I have just reached out to CNN and asked them to call (former NRC Chairman Nils) Diaz, and reached out to push the white house yet again to start talking on background or getting out in front of some of this crap.
On March 20, when Energy Secretary Steven Chu hesitated on CNN when asked if U.S. plants could withstand a 9.0 earthquake?
McIntyre, one of the agency’s spokesmen, suggested to his bosses what Chu should have said:
From: McIntyre, David Date: Sunday, March 20, 2011, 10:01:00 AM He should just say “Yes, it can.” Worry about being wrong when it doesn’t. Sorry if I sound cynical.
The public affairs staff showed disdain in the emails for nuclear watchdog groups, including the Union of Concerned Scientists.
After the UCS raised concerns about diesel backup power and batteries being inadequate, as at Fukushima, spokesman McIntyre dismissed it as “bleating” from nuclear power foes.
When Steven Dolley, former research director of the NCI and a reporter for McGraw Hill Financial’s newsletter Inside NRC, asked McIntyre for a nuclear containment expert to speak to a reporter, the spokesman asked if the reporter had contacted the industry’s lobbying group, the Nuclear Energy Institute.
Dolley asked, “So, should I say NRC is deferring inquiries to NEI?” suggesting that the NRC was deferring to the industry it is supposed to regulate.
McIntyre shared this exchange with his bosses, adding the comment, “F—ing a-hole.”
There is NO SUCH NRC REPORT!
The NRC’s Public Affairs staff attempted to discredit news reports that raised questions about nuclear plants, even when they were based on NRC data.
A story by this reporter for msnbc.com (now NBCNews.com) reported that the NRC had published a study 6 months earlier with new estimates of the risk that an earthquake could cause damage to the core of U.S. nuclear power plants. The plants were listed in alphabetical order, along with the NRC’s risk estimates.
The msnbc.com story, published on March 16, ranked the U.S. nuclear plants by those NRC estimates.
Surprisingly, the highest risk was not on the Pacific Coast, where plants are designed and built with severe earthquakes in mind, but in the Central and Eastern states, where scientists have raised their estimate of the earthquake risk since the plants were designed and built. The story said that the NRC still described the plants as safe, but also said the margin of error had shrunk.
We had checked our understanding of the report with NRC earthquake experts, but NRC spokesman Scott Burnell responded to the story by asking the same staff to find fault with it.
From: Burnell, Scott Date: Wednesday, March 16, 2011, 6:22 AM I know you’re going to have a cow over this – somewhat inevitable when a reporter new to the subject tries to summarize things. Apart from “you’re totally off-base,” what specific technical corrections can we ask for?? OPA (Office of Public Affairs) – this is likely to spark a lot of follow-up. The immediate response would be “that’s a very incomplete look at the overall research and we continue to believe U.S. reactors are capable of withstanding the strongest earthquake their sites could experience.” I’ll share whatever we get from the experts.
Senior officials at the industry’s lobbying arm, the Nuclear Energy Institute, sent emails asking the NRC for help rebutting the story. Burnell urgently asked again for errors in the article.
From: Burnell, Scott Date: Wednesday, March 16, 2011, 11:11 AM Folks, the expected calls are coming in — We need a better response ASAP!
But the NRC experts found nothing to correct.
From: Beasley, Benjamin Date: Wednesday, March 16, 2011, 12:31 PM I have received no concerns or corrections regarding the MSNBC article.
Nevertheless, the Public Affairs staff waved other news organizations off the story, particularly after New York Gov. Andrew M. Cuomo reacted to his state’s Indian Point nuclear power plant having the worst risk in the NRC data.
From: McIntyre, David Date: Thursday, March 17, 2011, 2:20 PM I just filed this request for correction with The Huffington Post, which has a report of Cuomo wanting to shut IP based on the MSNBC report: There is NO SUCH NRC REPORT! The NRC does not rank nuclear power plants according to their vulnerability to earthquakes. This “ranking” was developed by an MSNBC reporter using partial information and an even more partial understanding of how we evaluate plants for seismic risk. Each plant is evaluated individually according to the geology of its site, not by a “one-size-fits-all” model – therefore such rankings or comparisons are highly misleading. Please correct this report.
His colleague in Atlanta, spokesman Joey Ledford, replied, “Great talking point, Dave. I wish I had it during my 10 or so calls today trying to debunk this thing.”
The New York Times, which was reporting a story about Indian Point, was dissuaded from using the NRC’s risk estimates. We asked the New York Times reporter, Peter Applebome, why he ignored the NRC data. He replied in an email, “Burnell said it wasn’t accurate and included rankings the NRC never made. I have no idea if that’s correct, but I was writing a column on deadline and figured I did not have the ability to figure out who was right in the time I had.”
In his piece, Applebome quoted the NRC downplaying the risk: “Officials with the Nuclear Regulatory Commission say the site is safe and that its earthquake threat is on the lower end nationally and in the Northeast.” The NRC’s recent study with a different picture was ignored.
The NRC followed up with a blog post from Brenner, the public affairs chief, cautioning the public, “Don’t Believe Everything You Read.” Brenner called the msnbc.com report “highly misleading.”
He didn’t mention that its figures came from the NRC.
Emails excerpted in this report can be read in full here in a PDF file.
A cache of many emails is included in larger PDF files No. 1, 2, 3, 4, and 5. More are available in the NRC’s online public reading room.
Maps:
Age and safety record of U.S. nuclear power plants
How close are you to a nuclear power plant?
Adonis Diaries 