Save the World with Nuclear Power | Leslie Dewan | TEDxUniversityofRochester

[Applause] thank you all so much so I became a nuclear engineer in the first place because I'm an environmentalist I think that the world needs nuclear power alongside solar and wind and hydro and geothermal if we want to have any hope of avoiding the widespread environmental devastation that's caused by fossil fuels by coal in particular and so that's this is what really drove it home for me so this photo shows the air pollution in Beijing it's just one of the consequences of getting your power from the wrong source of getting your power from coal and you know on a bad day it's like being in a video game with a short render distance you can like see the buildings receding into the background and you can feel it in your lungs and some of it if you're proposing apartment free grid solar and wind are a fairly easy sell but then how do you incorporate something like nuclear power which is something that has a tremendous amount of baggage as well as some catastrophic failures in its past so and in addition to that nuclear also has issues with safety and waste and proliferation and cost as well as substantial public opposition in many countries so I'll be talking today about those issues and also about my work as a nuclear engineer and I'll be talking about some things I did that were successful and also projects of mine that failed and my personal story actually has some interesting parallels with that of the nuclear industry itself and so in telling my story I'll also be talking about the history of the nuclear industry and how it got to its current state and where we might go with it in the future the current public opposition to nuclear is something that's really interesting to me because it wasn't always the case so this shows the mobile radioisotope training laboratory that was put together by the International Atomic Energy Energy Agency here it is on the steps of the Hofburg in Vienna there were similar ones put together by the US Atomic Energy Commission and these were to teach nuclear technology to people so like in the in Europe they would go to cities they would go to small towns to explain to people what this technology was this photo was taken in 1957 they operated for several years and as you can see people were lined up outside the door to find out more and while Disney was also involved so in 1956 Walt Disney put together a book and accompanying animated movie called our friend the atom which you can find on YouTube that's amazing and in it he explained the science of nuclear reactor technology showing that ultimately it's just a fancy way of boiling water well at the same time capturing this inherent Wonder that something so small could be so powerful at the same time so to get into it in a little bit more detail this is a rescue mattock of how a conventional nuclear reactor works of how a boiling water reactor works on the left-hand side of the image this is underneath the containment dome you have the reactor vessel and this contains long thin rods of solid uranium oxide fuel in a typical reactor that are cooled and moderated by liquid water when the reactor is operating it's in what's called a critical configuration so you have a large stable number of nuclear fission reactions that generate a great deal of heat that heat is used to boil water into steam which drives a turbine which turns a generator which produces electricity and so ultimately nuclear reactors they produce heat they boil water they're like a tea kettle in the disney film at the same time as there was lots of innovative nuclear technology being developed in the 50s and there was all of this communication there were companies working on just some really out there nuclear products so this is the ford nucleons proposal for a nuclear powered car and nuclear powered airplanes that were proposed within the US and actually the soviet union built one which is completely out there and also nuclear-powered submarines this is the USS Nautilus which is the world's first nuclear-powered submarine which was completed in five and to some degree nuclear-powered submarines are why we got into this situation with the current nuclear power fleet in the first place so after developing the nuclear submarine the u.s. wanted to get civilian commercial nuclear power up and running as quickly as possible and specifically before the USSR did because this was right in the middle of the Cold War so here's the Shippingport reactor in Pennsylvania which started operation in 1957 and so you know the submarine reactors they're they're beautiful designs and they work extremely well but they're optimized for use underwater and so the u.s. because they wanted to get this up and running as quickly as possible instead of spending another decade to reoptimize a new type of nuclear reactor for use on land they took the submarine reactor and put it on wind and these work and they work well but the problem is that this type of reactor needs a constant supply of cooling water to pour over the rods in the core or else it heats up catastrophic Li so if you're in a submarine you can see how it's really not ever going to be a problem to have enough water around but when you bring that design on to land it suddenly becomes you know a somewhat difficult engineering problem so you need a constant external supply of electric power so you can constantly pump water over the core at all times while the reactor is operating and if you don't you have a meltdown and we did have those the first was at Three Mile Island 1979 then Chernobyl in 1986 and then most recently at Fukushima in 2011 and these nuclear accidents um in particular the Three Mile Island accident in 1979 served to stifle innovation people like you know it created a great deal of fear and it also meant that that sense of like blue sky optimism and open thinking really disappeared and the funding disappeared and engineers left the industry and everyone just hunkered down with what they and what they knew and it caused this period of stagnation for many decades but you know what's what if we could solve the underlying engineering problems what if we could go back to the early days of the nuclear industry and adapt one of the types of reactor designs that were tried and abandoned and update them with modern technology so one that was always very appealing to me is something that's called the molten salt reactor this is a top-down view of a prototype version of that that was built at the Oak Ridge National Lab and operated for several years in the 1960s so this is a liquid fueled reactor design and it's actually let me go to this diagram that shows its operation so on the far left you have the reactor core in which your liquid fuel is in a critical configuration so it has that same large stable number of nuclear fission reactions that produce heat that heat is carried across heat exchangers to a power production loop that boils water into steam drives a turbine turns a generator produces electricity but because it uses liquid fuel rather than solid fuel it has very different cooling requirements so if you have any interruption in your external electric supply the liquid fuel freezes solid and its melting point is at around 490 degrees Celsius so it's pretty easy for it to freeze solid and so that means if something goes wrong it fails in a solid mode rather than in a liquid or gaseous mode and at the same time this type of reactor operates at atmospheric pressure rather than the hundred times atmospheric pressure of a conventional nuclear reactor so you don't have that massive driving force that could potentially push things beyond the site boundary so at the Oakridge lab they built this they operated it they proved out the many safety benefits but there were some problems with it so the design was very expensive and had a low power density it required weapons-grade uranium this fuel which is suitable for a National Lab experiment but it doesn't work for rolling it out into commercial production and in in a world that hadn't yet experienced Three Mile Island or Chernobyl or Fukushima no one really cared about the safety benefits they weren't viewed as being particularly valued but um this design was just always exceptionally intriguing to me and so in 2011 when I was finishing up my PhD in nuclear a classmate of mine and I who's you know similarly environmentalist minded said okay well what if we can bring in tools bring in modern techniques to improve this type of design we said okay specifically we're going to look at you know material science advances from the 1980s better high-temperature alloys we're going to use modern computer simulations so we can improve the geometry of the design made some other materials changes and we were able to take the original molten salt reactor experiment much make it much higher power density and therefore lower cost and also to be able to run on low enriched fresh uranium fuel rather than weapons-grade uranium fuel well keeping the same safety benefits of the original design and we're like okay we are we are onto something here this is this is great um but I also told you that part of my talk is gonna be about failure so this is this is where we even the failure um so we had this great idea we were like okay we want to bring it out of academia we want to do something good with the world good you know for the world with this this was in early 2011 and a few months later Fukushima happened on March 11th 2011 and we said okay so what are we gonna do now is the world going to turn away completely from nuclear the way they did after Chernobyl and Three Mile Island and we said no okay what the world needs now more than anything clearly is safer nuclear power and so six weeks after Fukushima we doubled down and incorporated as a private company to commercialize our design and we then developed a design for a 520 megawatt electric reactor that's the right size for grid scale power generation so it's the right size to replace the coal power plants that are coming offline in the US and serve as an alternative for coal power plants that would otherwise be built elsewhere in the world and we have worked with the US Department of Energy on this and also raised funding from private venture capital as well in particular from founders fund who are interesting because they were the VC firm that put the first big money into Elon Musk's SpaceX so they like that type of you know a long time horizon like impactful kind of insane project um but at the same time you know there is still it's it's never easy there's you know technology redesigns and budget shortfalls and unexpected regulatory hurdles and you know my team and I when we were facing these difficult situations he said okay both what we want to do is sort of draw upon lessons learned from the nuclear industry itself and you know in the past when the nuclear industry has faced significant challenges they sometimes tend to close in on themselves and you know close ranks and not communicate with the public and that's to everyone's detriment and we said okay well just as we're drawing on technology nuclear technology from the 1950s we want to draw on their early and open communication styles and so when our company ran into into difficult times we said okay we're gonna open publish more of our papers and you know start more of a dialogue with people so they can learn more about our technology and actually people people really like that like they engaged it they like read these like weird dense science papers that we posted online and it was immensely gratifying and then at the same time there was something wonderful that was happening with the nuclear entrepreneurship sector as a whole so when I started transit Tomic there were maybe about five advanced reactor design companies worldwide and now there are more than a hundred and fifty of these companies that have raised about 1.8 billion dollars in private capital alone and they're all working on innovative solutions to these safety and waste and proliferation and cost problems and at the same time there's actually been bipartisan political support for this which is kind of mind-blowing to me so like even in this current exceptionally divided political climate there's unanimous support like not just bipartisan but a unanimous support for some of these bills that are coming down the line that make it easier to prototype and test some of these facilities at National Labs and I was lucky enough to be able to testify in front of Congress to kind of aid the passing of some of these bills which is very very gratifying in and of itself and at the same time I think nuclear engineers as a whole have been learning the value of communicating their work and you know starting these like basically definitely long conversations with the public about what the technology means what it works and when it fails and why it fails and you know how you how you adapt to that and that's important because of course not everything is going to be a success so I well a few months ago my company reached the end of its road and I had to make the hard decision to wrap it up and shut it down and so I had to make this really tough phone call to my investors and you know they knew that the company was going to shut down but I was gonna ask them for something really out there and so I called him up and these are like you know tough like Silicon Valley feces and I said okay what I want to do is put a ball put all of our work out into the public domain so that everyone can use it and it was it was actually quite beautiful they weren't they weren't on board with their plan with that plan so and you know they weren't just making an investment in my company they believed in the sector as a whole they believed in the carbon-free electric grid and so all of my companies work is actually now up on github and this is following careful review from the Department of Energy and the National Nuclear Security Administration so this is all copacetic on that front but we were able to put all of our patents out into the public domain anyone who wants to is able to use them all of our papers internal and external white papers all of our blueprints for the design as well this took a substantial do we review to make happen but they were on board with it and so I think that you know one of the most important things that I've kind of learned from this process is that you need to figure out how to learn from failure if you're going to be a good entrepreneur or a good engineer like there's sort of this myth that if you have a good idea that everything's going to be easy and it's going to just fall into place automatically but the reality is it's it's like beating your head against a wall every single step of the way and you know if you're running a startup you're you're doing something that's kind of out there and it's not necessarily going to succeed on the first iteration and you know as an engineer also like the most interesting cases are at the boundary conditions where by definition you're just on the cusp of failure you're doing something new and doing something different and that's a message really that I'd like to get out there is that you can it's crucially important to face failure and learn from it and be able to communicate it with people that's something that the early nuclear industry did well and that's something that I hope to do well in the future and I'm still deeply committed to advanced nuclear as a sector this is crucial technology that we need and I want to keep fostering it and I think that all of these new companies that are coming down the pike are developing technology that can ultimately decarbonize the electric grid and move us all away from fossil fuels thank you all so much you

Channel: TEDx Talks

Views: 47,973

Keywords: TEDxTalks, English, Technology, Business, Energy, Engineering, Entrepreneurship, Environment, Physics

Id: DoAcntoAVXE

Length: 16min 57sec (1017 seconds)

Published: Tue Jun 25 2019