Why making energy from dirt might save the world | Rusty Towell | TEDxACU

a few years ago I had the privilege of travelling to India I got to go and tour the Taj Mahal one the real wonders of the world but while is in India I also got to see firsthand what widespread extreme poverty looks like and one of the things I saw as I was traveling around India was small round disks lining the roadways just pile after pile after pile of them and I didn't know what they were at first and then I realized that this was cow dung that was being formed by hand in the small disk set out into the Sun to dry and after they dried they were stacked up put in baskets carried on women's head back to the home and that was the source of heating and cooking fuel for most of the people in India now this lady and the children that helped form these patties they don't need the United Nations or you or me to tell them this but the United Nations actually issued a report that said abundant energy can improve the living standards of billions of people especially in the developing world so when I think about what the world needs this is where I start I start thinking about how could energy change this lady's life and poverty around the world affects one in two people and I'm not talking about poverty like we might think we know it in this country I'm talking about extreme poverty where people are living on a couple bucks a day or less forty percent of the world's population still use animal dung or some other waste product to provide the heat for their home and their fuel to cook their food one in four people in the world have zero access to electricity so there's a real need for clean abundant safe energy to raise the standard of living around the world to remove poverty the world also needs a source of water one in ten people don't have clean water to drink but if you think about the other things we use water for to wash our hands to clean our food to bathe in to flush a toilet the normal sanitation function the water served force then one in three people in the world do not have adequate sanitation because they don't have water and finally if you're a man in this country you have a one in two chance over the course of your lifetime of developing cancer other demographics have other probabilities but we all know the cancer it is disease that doesn't really respect borders of countries or genders or other stereotypes of people and so we are all affected by cancer and when so when I think about the needs of the world I think about energy and water and a cure for cancer if these are the problems and these are the needs of the world well then what's the answer what is the solution thorium is the answer you didn't see that one coming did you well what is thorium thorium is just another element on the periodic table just like iron or tin or lead it's just a little heavier than those things but it's just a common element in fact if we go outside and we were to dig up a cubic metre of dirt something about the size of this box up here if we were to dig up that much dirt what we'd find is is that within that much dirt about one part in 100,000 is thorium and so that's equivalent of about the volume of three M&Ms so and that much dirt whether it's West Texas dirt or it's dirt from anywhere else or on the on the planet you'll get about three M&Ms worth of thorium out of that and you might say that's great for a snack but what can I do with three M&Ms worth of thorium three M&Ms of thorium is enough energy can produce enough energy to supply all the electricity I ever need in my life I say again all the electricity I need for everything I use in my entire lifespan can be produced from three Emsworth of thorium if I use that thorium and I produce energy in a liquid fluoride thorium reactor also called a lifter and so I'm going to talk to you today about this new type of reactor this new type of nuclear reactor that's able to provide for us the answers to the world's problems but before I start talking about lifters I need to tell you two things I'm going to ask you to work with me through these two things the first thing I want to tell you is that yes this is a nuclear reactor and so when we think about nuclear power many of us need to start by rethinking because we come to this with preconceived notions with stereotypes in the same way that stereotypes are dangerous and unfair and not helpful when we think about people and I would say there's just a lazy way of thinking I think stereotypes and we think about energy sources are similarly there so if you have an image in your head from a TV screen or something that maybe you're unfamiliar with or maybe maybe we're just scared of something we don't understand whatever it is I'm going to ask you today to rethink with me nuclear energy what is nuclear energy well nuclear just means it has to do with the nucleus the nucleus is just the center of an atom so if you have this cartoon image from grade school of what an atom looks like that's good enough for our purposes the little blob in the middle is the nucleus and the things flying around the outside are electrons there's a lot of things wrong about that picture but it's good enough for our purposes today and for our purposes today what I really want to tell you is that the nucleus is where everything that matters is and so if you have a chemical reaction where you you burn wood or coal or oil if you take hydrogen oxygen you combine two atoms and form water h2o you release energy and so we get energy out of changing the electron energy levels but if we change the nuclear structure of the atom we can get a million times more energy out of it and so that's a million times more energy from the same atom and that's why nuclear has the potential of producing a lifetime of energy for me out of three MMS in the palm of my hand right and so there's a million times more energy there the other thing I would like to tell you is at this point you might say we don't need nuclear power because we have renewables and I just like to ask you to think with me about renewables also renewables are not the answer because when we think about an energy source we we need to think about from the production of the power plant the fuel and the cost of operation to also to disassembling and disposing of safely at the end and when you think about the lifecycle assessment of dim energy sources what you find is is that what some of the things that you might have thought about renewables aren't the complete story and so you need to look at the whole picture and so if you evaluate them and ask is this source of energy cheap and clean and safe and efficient and available well the answer ends up being no no no no no for example we would love in West Texas for windmills to be the solution but but windmills can't be the solution because the cost of of building the the the windmills because of the the efficiency of them it takes years to get back out of a windmill the energy it takes to produce the parts and install it and put it in the ground if you think about the question is it cheap if if it's not cheap it really doesn't do this lady in India any good for it for government subsidies to be required to produce electricity and if you ask is it clean well we love to think about solar cells on the roof of my house producing electricity of being a clean source and it is unless you go back and ask the question where was that photocell built not in this country why why are they not built in this country do not know how no we know how to do it but to build photocells is a very toxic process that uses lots of toxic chemicals and so they're built in other countries like in China and so if you happen to be the man to pet this is his rice farm over the wall from a factory in China to builds photocells he has instead of a rice paddy he has a toxic lake of chemicals have been dumped over the wall from the making of these photocells so if you ask this man is this clean is this safe his answer is no it's making my family sick and so when we look at different energy sources you have to look at their complete lifecycle and when you ask questions are they available of course when the wind stops blowing and when the Sun sets these sources aren't there so renewables are not the answer so how is electricity built electricity is built whether you're talking about burning wood or coal or oil or concentrated solar power or nuclear power they all start with a heat source you have a heat source that produces energy and then the goal is to turn that heat into electricity and the steps that we do that is we we remove that heat through I'm a coolant usually pressurised water loop that energy is transferred to a heat exchanger at the heat exchanger that energy is transferred from one fluid to another fluid a lot of times pressurized water into water it's allowed this perform steam at high pressure the steam then goes through another pipe into a power conversion system something like a big turbine that's attacked to a generator that we get electricity out of so you start with heat source wind up with electricity and what I wanted a couple of things I want to talk to you about is what is the fluid that we use in this primary coolant loop here and for a liquid fluoride thorium reactor we use a liquid salt or a liquid fluoride that at high temperatures becomes a molten salt and so I saw just like your table salt sodium chloride this is similar except it's made with different elements made with fluoride and this fluoride salt at room temperature looks like crystals much like big salt crystals but if you take that material and you increase the temperature up to something like 500 degrees centigrade then it becomes a liquid and it flows it looks much like water it's clear much like water and it has the properties of water it can absorb huge amounts of energy and move it from the heat source to a heat transfer unit for a power plant and so this is the fuel this is the coolant that we use to remove the energy from our lifter and so where we put this we put this inside of a liquid fluoride thorium reactor and here I will start on this picture on the left with this reactor vessel this is where the fission process occurs this is where we're changing the structure the nucleus and we're getting a million times more energy out than chemical processes energy is released here and it flows through this liquid molten salt over here to a heat exchanger the energy is transferred to a working fluid goes through a turbine the turbine turns produces electricity because we started with the salt that's so hot there's enough energy left at this stage that we can actually use that energy to desalinate water so we can start pumping dirty water maybe salt water from the ocean or from the Gulf and and out comes pure water and so we end up producing electricity we end up producing water but the third thing we produce might be the most important and most exciting of all of them back over here in the core what used to be waste products from a normal nuclear reactor process we can actually now use to save lives as medical isotopes let me tell you how this happens and a normal pressurized water reactor that uses uranium is a fuel or plutonium we put that fuel inside of metal sleeves and we call it a solid fuel reactor and so that fuel is behind a casing of metal or ceramic and when the fuel breaks apart makes other things its lumped in with all of the waste all together so you end up with unburnt fuel waste and useful things that are just stuck in this environment and you can't get to them but because of this reactor design the fuel is suspended in this molten salt you can siphon it off chemically separate out these what we used to call waste but are actually medical isotopes and we can use those to treat and cure cancer and so we get medical isotopes out of this this reactor also that the final feature of this reactor that I want to share with you that's different than anything we currently use is because the fuel is suspended in this molten salt we can actually have a unique safety feature at the bottom of this reactor core there's a pipe that goes down into a drain tank and in that pipe there's a slug of this salt that's in a frozen crystal form and it stays right there unless something goes wrong with the reactor if something goes wrong with the reactor and the temperature starts to raise for whatever reason as the temperature and the core gets warmer and warmer then this plug would melt and then all the coolant including the fuel and the reactor drains down naturally into this drain tank and so when we talk about liquid fluoride thorium reactors we actually say that they're they're what we call walkaway safe because if you have if every reactor operator was to walk off the job if you were to completely lose power if everyone was to abandon and walk away from an operating reactor what would happen the in the primary core the temperature would go up the frozen plug of salt would melt gravity would cause it to drain down into drain tanks it would cool off naturally passively become hard crystal salts in kegs at the bottom of the reactor and released to the environment nothing to meltdown no hydrogen explosions in other words there's no chance of what happened at Three Mile Island or Fukushima to happen again with a reactor like this so we have a safe reactor if you're looking at this picture you're saying that looks like an old old drawing you're right what you're looking at there is a drawing of a reactor that was built 50 years ago in the 1960s at Oak Ridge National Laboratory this reactor this molten salt reactor experiment was built and operated for four years it used molten salt that used fuel nuclear fuel suspended in the fluid and it was used and tested and in working technology in the 1960s why are we 50 years later talking about it like it's a new idea worth sharing well unfortunately in the 60s the priorities of this country and the world were not can we make cheap energy can we provide water and can we get medical isotopes to treat cancer the the priorities in the 1960s in this country were how fast can we get a nuclear actor into a nuclear submarine and how how fast can we produce materials that can be used for to make bombs for the window arms race unfortunately you can't make bombs out of the materials from a lifter and so this technology was mothballed it's long past time that we as a nation and as a world take this out of the mothballs and use it again so what are the key or characteristics of a liquid fluoride thorium reactor I hope you understand how they can be safe safer than other forms of nuclear power I also want to tell you that there it's the cleanest type of energy you can imagine if we make all of our electricity out of a liquid fluoride thorium reactor how much fuel do we use how much waste do we generate well let's just take for example the city of Abilene if we wanted to power the city of Abilene produce all the electricity needed for the city of Abilene 120,000 people for a year how much oil would it take 33 million gallons give or take we're talking super tankers full of oil is what's necessary and when you burn 33 mil in gallons of oil you end up producing a billion pounds of carbon dioxide that's released in the atmosphere not to mention other toxics and other environmental damage if you want to power the city of Abilene with thorium you can do it all with the thorium you could put in a one gallon paint can this is enough thorium to power the city of Abilene electricity for a year and then you can ask the question well how much waste do we produce and there's actually zero carbon dioxide that's produced with the thorium reactor we don't produce any co2 so nothing's added to the atmosphere well what about the radioactive waste remember most of this gallon worth of thorium is actually siphoned off and used as medical isotopes to help treat and cure cancer there is some waste left over they don't make small enough cans at the store this is a cord it's not this much it's less than a quart of waste would be produced in operating the nuclear power plants for a year and so the amount of waste that's generated from a thorium plant is really small you could put it all in this one can and store it away cheap what's the cost of 33 million gallons of oil today's reduced oil prices were looking 45 million dollars what's the price to operate a thorium plant the cost to buy the thorium to produce electricity less than a penny a day less than a penny a day is what it would cost me for all the electricity I need and that's something that everyone can afford abundant fuel remember I told you in if you went outside and dug up this cubic meter of dirt you could get three Eminem's worth of of thorium well thorium is actually three times more abundant than tin and it's found around the globe and so every country has thorium mines and thorium reserves so it's something that the whole world has access to what do we get from from lifters we get clean cheap abundant safe energy and water and it's clean enough and cheap enough that it can be truly raised a standard of living of people all around the world we can also siphon off these medical isotopes let me tell you briefly about targeted alpha therapy this is just one type of experimental therapy the doctors are using bismuth-213 one of the isotopes that you can harvest from a lifter that alpha emitter doctors are describe it as a smart bomb for cancer cells you put it attach it to antibodies antibodies are ingested they go to the tumor and that delivers this radioactive material right to the tumor and this alpha particles are a thousand times more effective at killing cancer than normal types of radiation treatments and so when you look at this example down here here's a liver tumor before a treatment after a single treatment with bismuth-213 completely gone there is no trace of the tumors left now doctors want to do more and more studies with this but what they found is that there's not a source of bismuth-213 out there because there is not a lifter in operation and so there's a shortage of medical isotopes doctors use medical isotopes 65 million times a year to treat patients and they use it more except as a shortage of those isotopes I'd like for you to - thank you for thinking with me about thorium I encourage you to continue to rethink what nuclear energy means to you and I'm going to just challenge you to think about putting thorium in a liquid fluoride thorium reactor so we can get the clean energy and the water and the medical isotopes so that we can meet the needs of the world of building and developing lifters is truly a global service project thorium is the answer and I think that's an idea where Sharon thank

Channel: TEDx Talks

Views: 232,900

Rating: 4.7057796 out of 5

Keywords: TEDxTalks, English, United States, Science (hard), Energy, Physics, Poverty

Id: jDqCpfVwdP4

Length: 19min 37sec (1177 seconds)

Published: Mon May 11 2015

Reddit Comments

[u/dsws2]

I hope thorium lives up to its promise, but it sounds like snake oil in this presentation. Fusion is going to make electricity too cheap to meter. Hype Loop can be built for less than the cost of a two-rut dirt road. Thorium is going to save the world because people in India burn cow dung. They all sound about the same to me.

Wind is cheaper than nuclear, in terms of levelized cost of electricity from new generating capacity. He's not saying anything that's going to change that. If thorium had been ready to go, off-the-shelf, as a cheaper source of electricity than coal, for the past sixty years, I think some country's utility would have built them.

Disposing of waste heat from electric generation is a cost, when the source of the heat going into the turbine is coal, or uranium, or natural gas, or oil. Yet we're supposed to believe that if we change the hot side of the turbine from coal to thorium, that would turn the waste heat from waste into benefit. Bogus.

Thorium is an abundant fuel, at reasonable cost. This page cites an estimate of six million tons of thorium recoverable at a cost of $80/kg. In the TED talk, he makes it sound as though we'll be getting thorium out of ordinary dirt, for free. The same page characterizes molten salt reactors thus: "These reactors are still at the design stage but are likely to be very well suited for using thorium as a fuel." The TED talk makes it sound as though the technology was fully developed in the 1950s, and just not used because it wouldn't make nuclear bombs.

Coal doesn't make nuclear bombs either. He doesn't explain why that made us stop building thorium nuclear plants but didn't make us stop building coal-burning ones. I'll go with the non-TED explanation that molten-salt reactors, and thorium power in general, never got the R&D done. So we don't really know how much they'll cost, or how well they'll work, until we do the R&D.

[u/Yuli-Ban]

Ah, lovely thori— Sees TEDx Oh.

Well it's still an interesting talk.

[u/voltige73]

Anybody know about fission byproducts from thorium, and disposal methods? Duh, I quoted Polyanna Reddit to some random nuclear engineer and he said this is a huge problem. Ideas?

[u/AforAnonymous]

I'm still pissed the THTR-300 was shut down.

[u/quadium32]

This TEDx talk is about 20 minutes long, but worth taking the time to watch in my opinion.

Reddit: what are your thoughts on thorium as an energy source? I hadn't heard much about it before seeing this video, but now I'm intrigued.