Thorium. Is it the future of clean energy?

one thing's pretty much for certain in our increasingly unpredictable modern world and that's that now we've discovered it and found out how unbelievably useful it is we humans are extremely unlikely to be giving up electricity anytime soon and that means we have to keep making stuff happen at a fairly massive industrial scale all over the world in order to keep the juice flowing so to speak if we leave aside batteries and capacitors which use clever chemistry to make electrons flow and solar panels which are just God's way of messing with our minds then we're essentially left with the relatively straightforward challenge of persuading a very strong magnet to rotate inside a coil of copper wire or vice versa in order to induce an electromagnetic force which gets the electrons in the wire all excited and gives them a bunch of energy that can then be pushed along the electrical grid and into your kettle or Playstation or whatever so you need to find ways to make things spin it's one way very funny now let's scale it down please oh no that was it wind turbine is another one hydroelectric power or you can extract massive quantities of carbon rich fossil fuels from the ground and set fire to them in order to heat up a similarly massive quantity of water so that it makes steam so that you can force that across a turbine and of course for well over a hundred years that's been our very favorite way of making electricity it's extremely reliable and for a long time there seemed to be absolutely no limit to the amount of raw material available and then we realize that the carbon dioxide released as a result of the burning of all that raw material has heated up our atmosphere so much but it's now jeopardizing the future of most species currently living on our planet including our own so what we've been witnessing in the last few decades is a gargantuan global power struggle between the fossil fuel industry and the renewable energy industry and sitting somewhere in the middle of all of that quietly producing almost unimaginable quantities of more or less carbon free electricity have been the world's nuclear power stations hello and welcome to just other thing well back in the virtual studio this week to give ourselves a bit more space to look at a potential game-changer in nuclear power generation we all know about nuclear waste and in rashi mu and Nagasaki and meltdowns at Three Mile Island and Chernobyl and Fukushima all of those events were awful and all of them have undoubtedly tainted public perception of nuclear energy to a point where it might even struggle to keep its place in the electricity generation market as we make our way through the 21st century the people that work in the nuclear industry are all pretty miffed about any such possibility and that's because they know that a kilogram of uranium-235 which is a current nuclear fuel of choice it's capable of releasing many thousands of times more energy than a kilo of coal and they also know that the reaction that takes place to release that energy doesn't release any emissions of carbon dioxide and despite the three very prominent accidents that I just mentioned the overall historical operational safety record of nuclear power is actually very good so you could say that the biggest challenge the nuclear folks face is combating the almost universally adverse public perception of their entire industry which I imagine they must find quite irritating now this next bit gets a bit sciency and I'm not a scientist as many of you remind me each week so let's just give it a go and see how we get on this is the periodic table starting with the lightest element hydrogen up there as you get further down the table you get elements with more and more protons until you get right down there where you find uranium with 92 protons uranium occurs naturally in two different isotopes uranium-235 and uranium-238 which are essentially variations of the elements with different numbers of neutrons uranium-235 is 143 neutrons and uranium-238 has 146 neutrons which is where their atomic mass unit numbers come from uranium 238 is by far the most common of these two naturally occurring isotopes most nuclear reactors use refined uranium ore as a fuel because uranium-235 is fish which means it can be hit by a neutron and made to split up and release very large amounts of energy but because most of the uranium ore is the to 3/8 variety which is not fissile a great deal of extra energy has to be used to enrich the stuff they call yellowcake to increase the proportion of uranium-235 so that fuel is useful the mixture still has loads of uranium-238 in it though and that stuff is what's known as fertile which means instead of breaking apart when it gets hit by neutrons it absorbs a neutron and transforms into nasty waste products like weapons-grade plutonium 239 that's why this kind of reaction is called a uranium plutonium cycle as the uranium-235 gets hit by a neutron and starts splitting and releasing its energy it also releases more neutrons which then go flying around all over the place if those neutrons hit other uranium-235 atoms then you get a chain reaction and if you don't bother to control the chain reaction you get a nasty meltdown and eventually a fairly unpleasant explosion and radioactive fallout blowing across large areas and you don't want that the typical configuration of a nuclear reactor is a bunch of solid uranium fuel pellets inside fuel rods surrounded by large amounts of water a very high pressure the pressurized water acts as the moderator and the current to stop the chain reaction overheating and as it gets super heated by the reaction in the fuel rods it generates the very high pressure steam you need to drive the turbines and make the electricity good old water it's the gift that just keeps giving but once that uranium-235 chain reaction has been kicked off by the Neutron bombardment it's not going to stop for a very long time and there's nothing much you can do about it except actively and relentlessly manage the water cooling process to keep things safe and only disruption in that function and you've got a big problem in all three of the nuclear accidents at Three Mile Island Chernobyl and Fukushima it was the problems somewhere in the water cooling systems that caused the catastrophic failures and of course the wastes from uranium nuclear reactors including that weapons-grade plutonium stays dangerously radioactive for tens of thousands of years so if you could remove the long-term radioactive waste storage problem the short-term global security risk from the plutonium and most people would agree that would be a good thing and if he could also find an alternative to all that highly pressurized water in the system then you'd eradicate the possibility of steam explosions and potential generation of flammable hydrogen gas and that's a pretty useful factor of safety that the industry would dearly love to be able to sell to US consumers as far back as the 1960s nuclear physicists and engineers were working on an alternative nuclear energy system that they hoped would achieve exactly those outcomes it was called a molten salt reactor instead of using uranium as a fuel source the designers plan was for it to use thorium instead thorium's right down there in the heavy section of the periodic table very close to uranium with 90 protons and 142 neutrons in a modern salt reactor instead of using solid uranium fuel pellets inside fuel rods surrounded by highly pressurized water the thorium fuel is dissolved directly into superheated molten salt which then acts as the coolant and provides convective heat which goes through a heat exchanger to drive the turbine thorium is not fissile but it is fertile which means in a molten salt reactor it absorbs a neutron and goes through a series of reactions that transforms it into a fissile material specifically an isotope of uranium called uranium 233 uranium-233 splits very nicely in fact when it splits it releases more neutrons than uranium-235 and that tends to make the chain reaction more efficient and you don't get any annoying uranium-238 in a molten salt reactor either which means almost all the fuel is being utilized to generate energy as a result you potentially get a higher energy output per unit of fuel from thorium uranium cycles than you do from an existing uranium plutonium cycle and there's a safety side of thorium reactors because thorium is not fissile no matter how many thorium nuclei you packed together they won't continue their chain reaction after the initial bombardment of neutrons that means unlike uranium reactors if you want to stop the process you just stop firing the neutrons and the whole process shuts down and because the field and the coolant are a liquid mixture that liquid can be fed into the reactor more or less constantly without the costly and hazardous shutdowns required to replace spent solid fuel in uranium power plants molten liquid also expands as it gets hotter so if there's a system failure and it gets too hot then the fissile material gets spread too far apart to continue a chain reaction and the process shuts down without the need for human intervention but as an extra failsafe the engine is designed in a freeze plug below the reaction chamber so that if you did get overheat situation the freeze plug just melts and the molten liquid drains out into a safe storage vat where the neutrons can't reach and again the process shuts down automatically so in theory it's impossible to have a runaway meltdown accident and because there's no pressurized water there's no longer any risk of a hydrogen explosion from pressurized steam release and on top of that in its basic form almost all naturally-occurring thorium is thorium-232 which is exactly the isotope that can be used in nuclear reactors uranium or only contains three to five percent in useful material which according to the enthusiastic proponents of molten salt reactor technology means that thorium could potentially offer as much as 250 times the overall energy output of uranium and about 4 million times the energy of coal the thorium uranium cycle doesn't produce any of that rather inconvenient weapons-grade plutonium as a waste product either and although waste from thorium reactors is still very dangerously radioactive there's far less of it and it only stays radioactive for a few hundred years instead of tens of thousands thorium is also pretty abundant there's three times as much thorium in the Earth's crust as there is uranium and it can be dug straight out of the ground in a pretty standard mining process some estimates say that if we did find a way to mine and fish and thorium on an industrial scale and about $100 worth per person would provide each of us with our entire lifetimes energy needs or sounds a bit too good to be true doesn't it so why didn't we build molten salt thorium reactors when we first got busy with nuclear power back in the 50s and 60s well one of the most popular theories is that uranium stole them thorium back then precisely because one of its waste products was weapons-grade plutonium and during the height of the Cold War insanity our world leaders decided that that'd be quite a useful by-product that story may be true or it may be a total load of conspiracy theory codswallop doesn't really matter whatever the reason molten salt reactors just didn't take off back then and they remain no more than a theoretical concept today no molten salt reactors are currently in commercial operation anywhere in the world but eight years after the Fukushima disaster the nuclear industry is once again stepping bleary-eyed out into the bright light of public scrutiny to have one more go at world energy dominance in recent years there's been renewed excitement about molten salt reactors and particularly a variety called liquid fluoride thorium reactors or lifter for short right now at the beginning of 2020 there are at least 20 research centers racing to achieve a commercially viable liquid fluoride thorium reactor proposal including the United States Japan Denmark France and Russia China and India have huge quantities of easily available thorium so it's an extremely attractive option for them as well and one that both countries are actively researching and developing a pragmatist might point out that while here in the West were all busy removing meat from our diets and sticking solar panels on our roofs and rushing out to buy electric vehicles to minimize our carbon emissions all our efforts have been canceled out by the exponential economic rise and rapidly increasing energy demands of developing nations like China in India the majority of which is currently being powered by coal so you could argue that if new lifter reactors in those countries helped reduce the burning of fossil fuels to power their economic development then maybe we should be looking at them much more seriously but the technology remains unproven a commercial scale with many technical challenges not least of which is the chronic corrosion problem caused an assistant pipe work by the long-term exposure to the modern salts the nuclear industry is very conservative by nature it spent decades honing its safety systems and procedures to make failures like Three Mile Island and Chernobyl close to impossible in modern reactors the industry and its regulators look on the new molten-salt proposals with considerable skepticism and getting licences approved for those new power plants may prove to be an almost insurmountable hurdle the development and construction costs even for well established and proven nuclear power plant technologies have historically been extremely high and projects have experienced very long delays and then there's the glaringly obvious question of why we're not just throwing every available resource we have the renewable technologies even without subsidies the cost of these technologies is now lower than most fossil fuel electricity generation battery storage technology combined with smart electrical grids distributed across different continents and time zones look like they have the potential to create very stable well balanced energy provision for the vast majority of the planet if we adopt them multilaterally they're really big investors are watching those cost curve graphs of renewable technologies versus traditional energy producing technologies flipping so quickly now it need to be a very brave billionaire to sink your winnings into any nuclear power plant construction projects let alone a completely alternative commercially unproven technology there are some though and one of them is Bill Gates so we may well come back and check out exactly what he's up to in a later program arguably it comes down to this though the IPCC tellers we have less than 11 years to get our act together and put extremely robust measures in place to bend the carbon emission curve rapidly towards zero by 2050 and hopefully limit our planet's atmospheric warming to somewhere between 1.5 and 2 degrees above pre-industrial levels is 11 years enough time to design develop test license construct and commission a new wave of nuclear power generation plants on a scale that might significantly contribute towards the eradication of fossil fuels or do we plow on with the renewable energy strategy instead it's certainly a very contentious and divisive debate no doubt you've got a view on the subject and as always I look forward to finding out your thoughts in the comments section below that's it for this week though just time to say a huge thank you to all the FO to join the growing team our patreon page since our last program and give a shout-out to those people who recently started supporting the channel at $10 a month or more they are Mike Jones VJ dev Ramdev William Halford Jackson Blythe and Anders Hellmuth if you want to get involved in the just a birthing project and help influence the content of the channel through 2020 and beyond and visit our page at WWE and comm forward slash just ever think you can also support the channel absolutely for free by liking this video and sharing it with your social media networks and most important of all the best show of support is to subscribe to the channel and hit the bell icon so that you helped raise our profile with the youtube search algorithms to get the message of climate change mitigation out to as many people as possible you can do that really easily by clicking down there or on that icon there as always thanks very much for watching have a great week and remember to just ever think see you next week

Channel: undefined

Views: 155,238

Rating: 4.8600397 out of 5

Keywords: thorium, liquid fluoride thorium reactor, nuclear power, nuclear industry, nuclear waste, renewable technology, renewable energy, uranium, plutonium 239, uranium 233, uranium 235, uranium 238

Id: 8nUjvpxzFbk

Length: 16min 35sec (995 seconds)

Published: Sun Jan 26 2020

Reddit Comments

[u/Mind_lux]

Happy cake day!

[u/AutoModerator]

I hope you have a great cakeday! Share your cakeday and have a chat on the cakeday Discord.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/AutoModerator]

I hope you have a great cakeday! Share your cakeday and have a chat on the cakeday Discord.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.