Combating the climate crisis with next-generation nuclear | Eirik Eide Pettersen | TEDxArendal

did you catch the Chernobyl TV series that aired earlier this year you know the one with an exploding nuclear reactor crackling radiation detectors and mass evacuation if I told you that we should be constructing more nuclear reactors as if though our future depended on it many of you would think that I'm insane well I'm here to convince you that we should as long as it's done right that nuclear reactors can provide enormous amounts of reliable low-carbon energy on demand when it's needed and cheap enough that it can out-compete fossil fuels the nuclear reactors can be built inherently safe so that safety is ensured by the laws of nature eliminating the terrifying consequences of nuclear meltdown accidents let's take a step back some of you might be wondering why this guy is talking about nuclear at all well the problem is that we're not doing enough that despite our best intentions and efforts we are currently using way too much and we're not very good at sharing the population density in France in Uganda is roughly the same but can you guys see how the density of Lights differs this picture is taken at night from space and it gives an excellent idea of the energy use in these two countries it is a satellite image of inequality don't forget the number of people living on every pixel in France and in Uganda is approximately the same now that's insane in fact an average person in France uses approximately 100 times more energy than someone living in Uganda how do we fix this unfortunately it gets much worse because our house is already on fire human beings have never breathed an atmosphere with more co2 in it than today despite that last year in 2018 we set a new all-time high for burning fossil fuels the previous record reset in 2017 and before that in 16 then 15 and so on all the way back to 1982 the only exception was in 2008 when the world experienced a global financial crisis and people were forced to take the foot off the accelerator pedal didn't last very long though in 2009 we were back on track using more fossil fuels than ever before pedal back to the metal some countries are currently in the process of adding lights and catching up with the Western world to do so they are constructing fossil fuel power plants like there's no tomorrow on this map of Southeast Asia every yellow dot represents a coal power plant of a size that is proportional to the size of the dot can you see the massive one over there in Malaysia Dhawan alone corresponds to about 4000 wind turbines the pink and purple dots are fossil fuel power plants or coal power plants under construction or planning are you guys counting because I knew I had to and it turns out that there's 240 pink or purple dots that's 240 coal power plants under construction or planning in Southeast Asia alone then there's China there's India large parts of Africa even some countries in Europe that are doing the exact same thing this illustrates the heart of the problem that our primary means of societal development unfortunately happens to be the exact same the cause global warming so how do we fix this isn't it obvious we need new development machines and I'm here to tell you that nuclear could be one of them here's why nuclear power plants deliver electricity as carbon cleaned as wind power but on just a fraction of the land area and around the clock all day all year round very much like the fossil fuel power plants but without the emissions in fact it was this enormous potential for replacing fossil fuels that initially led me to become a nuclear engineer and I would ask myself all the time why on earth are we not building more nuclear reactors but I quickly realized that the nuclear industry is stuck it is stuck with an old technology based on solid ceramic fuel kind of like porcelain that is cooled by water under immense pressure it is stuck with reactors whose worst case scenario re-experience back in 2011 in Japan where a freak tsunami crippled the Fukushima Daiichi nuclear power plant in the resulting accident the Japanese government evacuated a hundred and fifty thousand people a third of which remained forbidden from moving back home to this very day that is a consequence that is simply unacceptable to the very people that these reactors provide power to now this problem is not something new it's something nuclear engineers have worked to overcome for decades and the approach has always been the same namely to make these accidents extremely unlikely to occur and considering that today or up until now we've built and operated more than 650 nuclear reactors over six decades and we've only had three major accidents we've gotten pretty darn good at it way better than any other energy technology however this unparalleled safety record has come at a price we have added a great many engineered safety systems to keep conventional reactors in check which has made modern plants extremely complex large and expensive consequently to pay back the huge loan required to build one the owner needs the plant to operate 24/7 that is simply put a very bad fit in modern electricity grids that increasingly contains small distributed and intermittent power generators such as wind turbines and solar cells as you might have guessed I'm not very happy with the status quo despite all of my initial enthusiasm about this technology I no longer believe the conventional nuclear reactors can be used to create the energy revolution that we so desperately need and I also see little evidence that the other energy technologies are up for the task at least at the pace required now I am nothing if not a pragmatist so again for me the answer was quite obvious I have to change this together with a handful of friends I have founded a company that will help fix global warming by developing next generation inherently safe nuclear reactors you see from the very beginning what we concluded was that people or what we need is a new technology that takes advantage of the benefits of nuclear energy the fact that it produces enormous amounts of low-carbon energy when it's needed and improves on the challenges most importantly we need to approach the topic of nuclear safety in new way we need to change the paradigm from complex expensive and added on safety to inherent safety from safety by engineering to safety by the laws of nature this means we need to change the fundamentals of nuclear energy and one way to do that is to change the fuel rather than using the sir make porcelain fuel that must be cooled by highly pressurized water we use this this is a fluoride salt it's a little bit like normal table salt except it doesn't dissolve very well in water and they won't add a lot of flavor to your food when mixed with fissile uranium and heated to 500 degrees Celsius it melts and turns into a transparent liquid that can be made to sustain efficient chain reaction this construction then is known as a molten salt reactor and that term is not simply a figment of my imagination these reactors have been built and experimented with both in China and in the US about half a century ago what they learned is that within the liquid salt uranium binds to four fluoride ions to form uranium tetrafluoride you can see it here when the uranium atom is ficient by an incoming Neutron it splits into two so-called fission products two atoms whose combined mass is approximately equal to that of the uranium minus some excess neutrons and heat produced the process will also release the four fluoride ions as free fluorine atoms within the molten salt now the thing with fluorine is that it happens to be one of the most reactive elements in the periodic table in the table of elements fluorine finds itself right next to the noble gases the noble gases are kind of like the coolest kids in school they're hip they're trendy they're full of confidence all the other elements want to be like them and fluorine so close but yet so far away is the most desperate of them all to become like a noble gas fluorine only needs to gain a single electron by binding to another atom any atom and it searches for this like a chain-smoker looking for the airport exit as the results as soon as efficient product is formed it is immediately bound by fluorine and dissolved into the fuel salt as a fluoride compound and since on average the two fission products will bind to three out of the four free fluorine atoms produced from fission there is always enough fluorine available this is totally different from conventional reactors in this solid porcelain like fuel the fission products exists the sort of smoke and gases so if for any reason there's a whole a cloud of radioactivity comes out and contaminates the surrounding land in a molten salt reactor the radioactive fission products are chemically bound within the fuel salt it would be just as hard to get those fission products out of there as it is to separate the rum from the soda in a Cuba Libre actually it would be much harder because you can't even use your liver unlike a Cuba Libre the fuel salt also won't mix with water and it won't react with air so even in an absolute worst-case scenario worse than Fukushima think someone throws a stick of dynamite into the reactor those fission products are stuck within the fuel salt and when the salt cools down it will solidify and the cleanup will consist of picking up radioactive rocks just like this one challenging no doubt expensive you betcha but it is a cleaner that is contained within the fences of the power plant that will not require hundreds of thousands of people to evacuate and they can be completed within a reasonable time and cost both financial but more importantly human cost as a result of these and other inherent safety features it is possible to construct molten salt reactors that not only create a ton of clean energy but that also cannot melt down or explode like conventional reactors simply because of the laws of nature and since the fluorine is so desperate for that last electron you can dissolve all kinds of stuff into the fuel importantly that includes plutonium also known as that nuclear waste that we have to store for millions of years in other words molten salt reactors can use this waste as fuel and turn it into carbon free energy it will still produce waste obviously all industrial activities do but waste that must be stored for hundreds rather than millions of years the end result is a new nuclear reactor with a tremendous potential keep in mind since the safety is ensured by the laws of nature instead of expensive engineered safety systems these reactors can be very simple and simple means cheap cheap enough that they can out-compete fossil fuels cheap enough that development countries will race to build inherently safe molten salt reactors instead of coal burning power plants cheap enough then to overcome global warming and provide lights to a world that continues to develop and prosper thank you [Applause]

Channel: TEDx Talks

Views: 12,243

Rating: 4.9012346 out of 5

Keywords: TEDxTalks, English, Global Issues, Change, Climate Change, Engineering, Environment, Future, Nuclear weapons

Id: CiyrwAM7-LE

Length: 14min 59sec (899 seconds)

Published: Fri Dec 06 2019

Reddit Comments

[u/Rocket2112]

Nuclear is a great answer. Why is everyone being blind to the waste caused by solar?